So, you want to learn to fly by radio control. This is how you begin:
By Carl Murphy
I often put a radio controlled airplane a hundred yards in the air trimmed for a slight climb, give
somebody the transmitter and leave. “What should I do? Just fly the thing! And if it crashes?
Go and get it, I’ll be back in five minutes” With an expensive airplane where fifty hours of
assembly were at stake that would be unthinkable. With a Foamie that is difficult to ruin and
easily replaced in a few hours it is downright entertaining. Beginners often first develop self
confidence when they have no other choice. I was the champion of my club at flying
inexpensively, and still enjoying it. Over and over other pilots have come to me to thank me for
helping them learn to fly, It wasn’t usually their first flights, but rather in the phase where they
had learned how fast things can go wrong and didn’t trust themselves to fly alone.
In comparison with my other hobbies I don’t have to worry about hypothermia, game wardens,
hearing damage, being broken up, getting run over, hangovers, getting back across the
boarder, veterinarian bills or jealous husbands.
After flying airplanes by radio control for fifteen years now, about a hundred different airplanes,
(the majority of them simple and inexpensive, all gliders or electric powered, including 48
flying wings) and regularly teaching new pilots; I have some specific recommendations. But,
there are others with just as much experience and success, their choice of methods and materials
is different and they would probably classify me a fool for what follows. As usual when that
happens it demonstrates that there are other factors involved, or maybe what they thought was
important, isn’t.
There is nobody that spends as much time in the air with less time spent building or cash outlay.
I often fly at locations that are not “landable”. Or I check if the conditions are suitable for slope
soaring. Or I investigate how the wind aloft is. Often the other pilots, with their expensive and
fragile airplanes are prisoners on the ground while I play with the unseeable opponent. I, the
shame of the club, often fly the worst looking airplanes, and I am proud of it. Flying is only
learned by flying, the scares from the repairs are the evidence for it.
Long ago when I learned electronics, the best introductory book began with what was actually
the most complicated first and went backwards to the details from there, so does this set of
instructions. Try reading all the way through first, and then again, there is more to it then can
be understood quickly. There are plenty of books for beginners already, but they can’t risk
being specific. Since this is just for my friends and club member here is what the other books
left out and some of what a publisher wouldn’t dare to print.
For those of you that have questions:
The airplane itself, that is so enticing in the store, is, measured in purchase price, the cheapest
part of the whole thing. Traditionally youngsters after countless hours had created something,
that after the first, all to short, flight attempt was just a pile of wreckage. Now, many years
later they see me flying and it occurs to them, hey, that is possible! It is for those of you, that
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so often have asked me about flying that I wrote this booklet for. There are already plenty of
books for beginners. Here are my personal conditions for learning to fly.
What you should I learn on:
The era where home-builts were rewarding, at least for beginners, is past. You must not fall in
love with your first couple of airplanes. The first planes should be purpose machines that exist
for learning to fly. I recommend foam airplanes that are nearly completely built and have the
motor in back. The motor in back because with every bump, and there are going to be lots of
them while learning, the plane lands on its nose. When the power-plant is in front the whole
thing, including all enthusiasm, gets wrecked. The previous cannot be overemphasized. No
matter how unconventional a foam airplane with the motor in back at first appears, it is
the best way to learn to fly.
Having the motor pushing has disadvantages: The noise from the propeller is a lot louder, the
propeller has a lower efficiency, and it looks odd. We want foam because it is simple and quick
to build with and can absorb an incredible amount of impact. They can now cast in foam a better
airplane then you could build yourself. If you invest less of yourself by spending intensive hours
building you are much more able to concentrate on actually flying. As soon as you are soaring
overhead while the others are on the ground making repairs, how the airplane looks ceases to
matter. The most common “I can’t get it” reason is too little time in the air followed by too
many hours spent fixing.
What it costs:
When it comes to money there can be big differences, but there are guide lines. If you want to
get going with a minimal outlay and buy everything new about (500) dollars, and a few more
hundreds after that. It sounds like a lot, but some of the equipment lasts for years. If you really
want to learn how to fly don’t try it for less then five hundred bucks. If you have somebody
helping you and get some of the equipment used maybe a couple of hundred less would do. But,
with the simple new all inclusive sets that start at (130) dollars even we, who already know how
to fly, have difficulties taming them. The satisfaction is not measured in the money you spent,
but you need to spend enough that the equipment actually reliably works. When I am piloting a
remote controlled airplane I am freed from the ordinary, without the expense or danger of siting
in it myself.1 Flying is a complete experience that is not measured just in money or time in the
air.
As a beginner, if you have help, you may expect about 50 flights from your first airplane. I
have had flying wings that made 750 flights (even if the equipment then limited the powered
1
See the follow on section about man carrying airplanes.
2
portion of the flights to 4 minutes), but two, that were blown away by the wind, didn’t even
withstand their first flight.
It always happens, you find yourself in a hobby store and just have to have something that isn’t
planned for. Airplanes that should have been your fourth one, or motors that just look so cool
ectera. It doesn’t matter what your age when you enter the hobby, if you find yourself in a
model store it’s going to happen. The time required varies. And you should have insurance. It
is possible to get started alone, but only for special people, and even then it isn’t recommended.
It used to be that we experienced small aircraft builders were pleased when the construction of an
airplane was completed in three to five working days. With balsa I expected three to five times
as long for repairs as building as it took to originally build the airframe. The airplanes were
continuously damaged. With flights that, on the average, lasted up to twenty minutes, it took
about a hundred flights to get a one to one building to flight time ratio. Which only few (very
few) airplanes withstood.
A prebuilt foam airplane, after you have some practice, is ready after two to eight hours.
Verifying that the radio and equipment is functioning correctly takes about as long as the gluing
together. If flights last twenty minutes, and they may often be longer, the plane in the hands of
a capable pilot easily lasts twenty times as long in the air as the building took. The end of a foam
airplane is usually the result of either foolishness for a total write off, or material fatigue.
The Airplane:
The Easy Star from the Multiplex company. Simple and fast to build, easy to fly, not easily
damaged and then usually with a minimal expenditure to get it back into the air. It looks like
nothing you would ever see at a man carrying airport. Please, for the first airplane forget the
wish that the plane looks like something in which you yourself could sit. No airplane that can
carry passengers would ever withstand so many impacts as your first remote controlled must. In
principle what we want is not a model but a flying learning device. The Easy Star has,
depending on what it is fitted out with, either the from the manufacturer 30 watts (1/25 of a
horse power) output, with which it may only be used near sea level on days with no wind, on up
to 350 watts, at which the propeller whines and it can almost fly straight up. For beginners 60 to
120 watts output to the propeller seems to be best.
Thanks to the motor being above and behind the wing and elapor foam an Easy Star can
withstand the impact of a steep dive from ten foot high into the ground and (after straightening,
glue and tape) be flow again, any other airplane would be ruined. Sometimes to convince
people of the advantages of elapor I stand on a wing. I used to weigh in for competition at 218
pounds, nothing happens. The spinning and flipping on landing, that would otherwise cause so
much damage, are mostly just absorbed with no damage by an Easy Star. Even after the
airframe is no longer repairable most of the equipment can usually be used again. It can be
landed almost anywhere. That with the land almost anywhere is very important, even at the club
airfield beginners often land off the runway, way off sometimes.
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Flights with the Easy Stars last from twenty minutes up to hours. To date boredrem (after
determining that the mechanical connection of the wings is only effective for about fifty times
and has to be improved) and foolishness have set the limit on durability. My four personal Easy
Stars lasted the following flights respectively: 215 flights, fourth set of wings separated in the
air, 350 flights, wings separated and landed in the ocean, 277 flights, radio receiver quit, I
have a photo of the airplane 50 feet up a tree somewhere in the impenetrable scrub forest of the
Santa Ana River, 351 flights, a beginner lost orientation at the end of a dive and shredded it by
flying through a tree.
If you have help you may expect about fifty flights from your first airplane. If you try to go it
alone it your first airplane(s) probably won’t last long enough to get a whole minute of flying.
The Radio Controls:
Hitec/Multiplex offers a complete Easy Star package with everything that is needed for flight
(even if some of the stuff only barely works) for the affordable price of $190 (plus tax and
transmitter batteries). Included is a simple 3 channel FM radio control with two servos, it is
entirely adequate. The German version costs Euro 210, that includes a 4 channel FM radio.
Any radio must have a full range (at least a thousand yards, few people fly further away then
that), the ones for Park Fliers are not for use with the Easy Star. The range of an ordinary radio
is much greater then you can see the airplane, at least a mile. If you are buying a new radio
separately, get one in Gigahertz (the frequency band of mobile phones) and quit worrying about
interference. I like the ones from Spektrum, now everybody seems to offer one.
Although my personal recommendation for your first radio is to get the simplest possible, there
is a vast array of radios available, most of them require programming. To which I can only
recommend, use what the people you are going to fly with know how to get to work.
For the Easy Star I recommend servos from Hitek in the size HS 81 with the ordinary plastic
gears, or similar. They are exactly the right size and exactly fit the hole made for the servos. It
is possible to install smaller servos, I’ve had the smaller lighter HS 55s last 400 flights, but the
control arms broke sometimes, in the early 2000s about a fifth of them had centering problems.
Only experienced pilots should install servos smaller then HS 81s, nobody needs bigger.
“Standard” size servos, often included with a radio, will not fit in an Easy Star. I’ve used about
a hundred HS 81s and have yet to have a problem with them. See below, I am no longer
allowed to show others how to build, or fly, flying wings. Although there are a variety of final
output gearing materials available, the basic plastic level works reliably in an Easy Star, you
don’t need metal gears. Better servos offer smother travel, more exact positioning etc, but that
is not an advantage with the Easy Star. The servos installed in the prebuilt Easy Star, are,
packaged under the Multiplex name, Hitek HS 81 servos.
The electronic speed control for the motor also supplies the receiver in the airplane with all the
required current, except if you use a high voltage battery. Any electronic speed control that you
can buy shuts off the motor before there is too little power left for the remote control. Even
when the motor controler cuts the motor off the air you have a long while left to land.
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If you are going to use more then 10 Nickel Metal Hydride cells, or more then 3 Lipo cells, you
either know what you are doing, or you are going to have to get a more expansive instructions.
You really don’t need more, I have built Easy Stars with up to 820 watts provided by 3 Lipo
cells. That exceeded the upper limit. With one horse power at 38,000 RPM I was afraid of
cutting my fingers off, the whole airplane shook long before getting going as fast as the motor
could push it. And the noise...
The Motor Beginnings: Updated for 2011
It used to be that we had two typed of motors, brushed and brushless. And, we had two types of
batteries, Nickel based NiCad and NiMh plus Lithium types, mostly LiPo. Brushless motors
are still included in some Multiplex kits, but they are being phased out, the performance of
brushless motors so far exceeds brushed motors that nobody wants the old ones anymore. At a
swap meet you can’t give brushed motors or their controllers away. The batteries for flight are
now all LiPo types, even though in the event of a crash the NiMh batteries held up better, LiPos
won out. At a swap meet NiMh flight batteries are now worthless.
If you are just starting out my recommendation for a flight power combination is to buy the
combination Multiplex offers. That inrunner glues right in and provides at least hundreds of
wonderful flights. Even after you crash an Easy Star enough times that purchase of a new
airframe is a better option then repairing it again, the motor and controller usually can be reused.
At the end of 2010 I went through my accumulation of flight stuff while building up another
Mini Mag. Although it leaves out a whole lot of parameters, an estimate of how high an
airplane climbs during a count of ten and then how long it takes to glide back down give a
relative performance comparison. I didn’t even try a Speed 400, long case Speed 400 or long
case Speed 480. I did have a pair of ball bearing brushed cobalt magnet motors that are a big
(30% relatively) improvement over long case Speed 4XX motors, and they were wound for
voltages that a 2S LiPo would provide. Keep in mind that big is relative, the difference between
batteries, almost trivial, can be more then the total difference between a ball bearing and plain
brushed motors.
With the Cobalt motor and modern 1800 mAh 2S LiPo battery flights lasted about ten to twelve
minutes in still air, almost all of it a full 13 amps. It would climb about 50 feet during a count to
ten and took a count of ten to glide back down. Any wind over 5 miles an hour where it could
not have been slope soared would have made the airplane near useless. If you are reading this
for an introduction to flying, you aren’t ready to surf an updraft, yet.
When the 120 gram motor and prop were exchanged for an inexpensive 40 gram outrunner, with
the same battery, the Mini Mag would climb about 230 feet at a count of ten and take about 45
seconds with a windmilling prop to glide back down, or about 55 seconds after fitting it with a
folding prop and a speed controller including a brake that would stop it from continuing to free
wheel turn with the amps off.
With a better then cheap 80 gram inrunner on a 2S LiPo the climb improved to about 300 feet at
a count of ten (at the same 20 amps), and the glide back down went to about 75 seconds. With
the same 80 gram inrunner and a 3S Lipo (80 grams heavier then the 2S) the climb was so high I
could no longer get a really accurate estimate, it looked like about 800 feet, and the glide back
5
down took over a count of 100. May I recommend not bothering with NiMh batteries and
brushed motors! The section on brushed motors is included for reference only.
Brushed Motors: This section is obsolete
Included with the Easy Star kit is a well known small motor type Speed 400 in 6 Volt and either
a white or black plastic propeller. The motor is intended for use in an airplane. Even if not
visible from the outside, there are two little suppression condensers built in, they are essential.
If you use direct current (brushed) motors only use those intended for use in an airplane, that
therefore have the condensers. Both the Speed 4xx motors and their black or white propellers
should be placed in retirement.
For use in the Easy Star the propeller absolutely must turn clockwise as seen from behind, which
with the previously supplied white Gunther proper meant removing it from the hub and reversing
it. About 2008 the black Multiplex propellers became available. They were optimized for the 30
watts-out of a Speed 400, both the black and white propellers are now obsolete, nobody wants
to fly with that low power anymore. The black propeller is optimized for 30 to 40 watts-out,
although ideal for the Speed 400, it is not suitable for the much more powerful brushless
combinations available today.
For some reason pilots experienced with combustion machines were difficult to convince that in
pusher configuration that the propeller must turn in the forwards direction. It’s weird how they
refuse to accept that. The direction which the propeller must turn is determined by the propeller,
not by the power plant. Modern brushless electric motors may turn either way by just changing
the order of the three wires connected to them. The fourth most common reason for “it won’t
fly” is that the propeller is installed backwards.
The motor may be used with Nickel Metal Hydride (NiMh) batteries (Nickel Cadmium,
otherwise known as Nicad are, because of the smaller capacity almost no longer available)
which deliver an average of 1,2 Volt per individual cell. With six cells and therefore 7.2 Volts
there is just barely enough to fly the airplane. If you bought the complete set from Multiplex up
to about 2009, just such a battery was included. The goal of such a minimal motor output is that
it is just possible for a beginner that is experienced with video games to teach himself (lady
pilots, sadly, are very rare) how to fly with a minimum of financial outlay. Conditional
however is that there is no wind at all and they are near sea level. I have observed it five cases,
all of them were experienced RC model auto drivers. However, they were better off with help.
Even if you are nearly broke I recommend not using the supplied 6 Volt Speed 400 motor in an
Easy Star, get at least a long case Speed 400 or 480 instead. Nobody else wants them anymore
and they are cheap to buy. More about that in the Examples section. But somehow that shinny
new motor just demands from a lot of people that they use it anyway. An Easy Star will fly on a
Speed 400 and 2S Lipo battery, but when you see how much better the modern stuff works
remember that I tried to convince you to just set the Speed 400 off to one side...
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The german language text originated in 2007 when NiMh batteries and brushed motors were still
common. This is 2009, things have changed and we can skip most of that. Do yourself a favor
and go straight to alternating current (brushless) motors and lithium Polymer batteries.
Motors Continued, Brushless:
We used to use direct current motors where the electricity was transmitted from the fixed case
with it’s magnets to the windings that were wound on the rotation output shaft through
mechanical brushes. The motor took about a flight to wear in the brushes, delivered flat, to
being round to match the armature and from then on started wearing out. Although the
manufacturers play the numbers game by listing them as having an efficiency of as much as
75%, at the power levels required for flight they turned more then half of the power put into
them into heat instead of turning the propeller. That’s right, the actual efficiency was about
45% to 55%. The unrealistically high numbers also didn’t take into account the increased
friction from the propeller pulling on the output shaft. You could confirm that with your fingers,
they got hot. Let’s just forget about them from now on.
Almost everybody now flying is using alternating current i.e brushless, motors which have no
mechanical connections that transfer electricity to wear out. The position of the magnetic flux
that pulls the output shaft around must be continuously varied as shaft turns, that varying
location of the center of magnetism is now created by the motor speed control. How that lead is
created, and how much lead to use is more complicated then can be explained here, and you
don’t need to really understand it yet anyway. Just remember that the better controls, which are
more expensive, do a better job, and require some experience or help to get set right. For your
first couple of controllers get a simple one such as the Multiplex ones, or my current favorite
from Castle Creations.
The internal description of what happens inside a motor is on a complexity of E equals MC
squared, you can still get a Ph.D. investigating wound coil magnetic interactions. I want to fly,
not do calculations. If you look at an electric motor under the hood of a car, or at a household
fan, or almost any electric motor except in a radio controlled airplane, the magnets are fixed to
the outside of the case and the wire windings are attached to the shaft that rotates. This works
fine, except that the dynamics require higher rotations per minute (rpm) then the propellers our
little airplanes require. It is possible to reverse the parts so that the outside turns and the wire
windings stay put inside, this is called an outrunner motor. Accordingly, the traditional motor is
now called an innrunner. Although currently about 85% of the market is for these high torque
outrunner jewels, since for the Easy Star the outside of the motor is glued in place they are not a
good choice for that airframe.
Until we took up using electric motors to fly our little airplanes only a mechanical or electrical
engineer needed to know anything about how to select an electric motor system. When we first
started flying radio controlled airplanes with electric motors we mostly used stuff from the model
auto set, and for a while we used their descriptions. That worked fine until we moved away
from their sizes. That old discussions of the number of windings is not going to be applicable
until after you have enough experience to need a more advanced guide then this one, we now
use the engineering values.
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Even a cheap brushless motor way outperforms a racing brushed motor. For a while brushless
motor controllers were more expensive then brushed controllers, then they were about equal
priced, now nobody flies with brushed motors so the comparison no longer matters.
Along with it’s physical size, the basic description of an electric motor’s characteristics is it’s
kV coupled with how many watts it can accept as input. The kV stands for the number of times
an unloaded motor will turn per applied volt in thousands of rotations per minute. There are a
bunch of additional criteria, someday when you get to playing with the virtual dynamometers on
the internet you’ll see them, but this is the most basic numerical description to use for
comparisons. The output of any motor is a result of it’s own construction, the voltage applied to
it and how the controler handles the lead, and the load i.e. the propeller at the actual flying
speed. It’s intricately interrelated, trial and error are how we determine what works although
with computers to handle the basic investigation of what to use it goes a lot easier. When
airborne recording became available we were surprised at how much less amperage we were
actually using then presumed. With Lipo batteries you are going to be flying an Easy Star on
either 2 or 3 cell batteries. For an Easy Star you need an inrunner in the diameter of 28 mm with
a kV of between 2500 and 3500 weighing around 75 grams. That is the shortest size of a
standard 28 mm inrunner motor. For a view into complexity a motor with the same kV that
works fine in the 28 mm diameter 75 gram size is useless in the next size larger (either a larger
diameter or longer length) in an Easy Star. You are restricted by the Easy Star airframe to a 6
inch maximum diameter propeller.
An all encompassing explanation of selecting a motor would require an engineering type text
book. An Easy Star is an defined airframe, so I can make seemingly definitive
recommendations. Be aware though that although these are seemingly exact values, that nearly
all of them vary more then most of you will ever understand. The kV of a motor varies, the lead
from the controller, load (which varies with airframe speed) and rpm and so on and so forth.
The pitch of the prop is not a constant hard number either. The battery voltage varies with it’s
charge. If you find yourself hopelessly confused, Multiplex offers well balanced propulsion
systems for each of it’s airplanes at a price that you cannot as economically collect together on
your own. See above, the airplane is the least expensive part of the whole package, the
propulsion system costs more then the airframe. Otherwise, try using what the other people you
fly with are successfully using. Along the way it will start to make sense. Electric flight is
vastly easier then fussing with the fuel burners, but you still need some personal ability to fiddle
with things or some help. Most of us needed both.
I cannot afford to be a member of any of the local flying clubs in Germany, but sometimes I just
hang out there anyway. Model airplane clubs are nurds at critical mass, just about all of the men
have a more continuous connection to having been boys then the average population. One nice
day there was a teenager that wanted to learn to fly waiting for a club member to show him about
it. But there I stood with an simple rear engine foam airplane, so, a club member was enlisted to
use my airplane to teach him how to fly. Turn the transmitter on first, push in the wings, attach
the battery and close the canopy. Climb out to about fifty yards and just go fly. That’s all there
is to it with a correctly tuned electric airplane. The time required to get in the air, less then one
minute. When the battery ran out at twenty minutes it bounced off the ground on landing. We
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just laughed, pushed the wings back in, checked for damage, swapped in a fully charged
battery and went right back up. When the assigned trainer showed up it took an hour with a box
of support equipment and fussing around to get a fuel burner into the air. The kid kept looking at
me as if to ask “is all this necessary”. When it crashed, because the engine quit in the air, it cost
a day and a half of repairs and a hundred Euros worth of parts. All that time spent breaking in
the combustion engine was wasted!
Many traditional model airplane enthusiasts reject foam airframes and despise the ease of
electrics, a portion of them refuse to learn how they work. For them the satisfaction of flying an
airplane they personally painstakingly glued together and shrunk the covering on, the smell of
nitromethane, the constant fiddling with their unreliable reciprocating power plants and the
scream of the combustion engine spraying castor oil all over everything are all inseparable parts
of the experience to them. I’m in it to fly, they can keep their fragile filthy noisy things. One
day near Frankfurt am Main at a flying field that has everything from the oldest to the newest, a
power pilot wasn’t satisfied with the performance of his new electric powered airplane and
decided to change to a larger prop. We all told him to measure the current draw, which he
refused to do, the motor quickly burned up in the air. Another pilot whose 3 meter wingspan
Euro 2000 model he nearly nailed (his day job is an airline copilot, you can almost see
Germanys largest airport from the field) laid in to him that Lipos need to be at about the inner
temperature of your body (90 degrees Fahrenheit/35 Centigrade) to work best, since he had
launched with them at near freezing as they heated up the increasing current overwhelmed the
motor. I then laid a model out where the components could easily be swapped out and proceeded
with a watt meter to demonstrate to him the changes in current draw by changing propellers,
batteries and motors. Half of the club came in to watch. At the end I deliberately over proped it
to show him how the motor and controler heat up, when they have absorbed all the heat they
can, they burn. Then I put a correct prop on and insisted he go fly my airplane. He got with it
and learned how to use electrics.
It’s reminiscent of the discussions thirty five years ago when iron on shrink covering first
became available about how real airplanes had to have silk and dope covering, traditions die
hard.
The Charger: this section was updated for 2011
By the time you read this Hitek may have changed the charger in the complete Ready to Fly set,
if it’s still for NiMh only you can still use it to charge the transmitter battery. LiPo batteries are
much more sensitive then NiMh batteries were, but worth it for the flight pack and they are
increasingly being used for everything. LiPos require a charger that can specifically charge them
and a means of balancing the charge between the individual component cells. Get help with the
selection. If you have no other guidance pick them from the Multiplex catalog, make sure you
can balance the individual LiPo cells.
That simple transformer based charger included with many starter all inclusive sets works fine
for the equipment in the set. However, usually it has to be plugged into wall current, the rate of
charge is matched to the battery that came with the set (so it either can’t be used with smaller
capacity batteries or takes a long time with larger ones) and it provides no information about the
9
battery and charge other then low (red light) or charged (green light). Sometimes simple is
better, however the better chargers with a display provide a whole range of information about
the condition of the batteries that you are going to need. Get a full range charger as soon as you
can.
When LiPos first came on the scene the manufacturers tried to adapt then existing charging
equipment, which only sort of functioned. The issue was that while NiMh batteries in series
(one right after the other) balanced themselves, LiPo batteries individual cells develop
increasingly different voltages if charged as a single block. The voltage range of LiPos is
critical, after enough charging cycles the differing voltages resulting from charging all of them
in series produced not only a well below optimum charge, eventually one of the cells either
under or over charged and chemically self destructed. For a while we just ignored the problem.
Then there were various add on solutions, an effective and lowest cost one was the Astro Flight
Blinkie balancer. The real solution was to equip each individual cell in a battery pack with it’s
own lead that was hooked into the electronics of the charger to level out the charge between the
cells. Eventually all the chargers were fitted with balancers. The remaining problem being that
the connectors are not yet standardized.
If you are nearly broke and still want to fly, new or nearly new LiPo batteries can be used for a
few flights without balancing. And, you could get by a little longer by have somebody with a
balancer equipped charger balance yours once every five to ten flights or so. Some LiPo
batteries do just fine for a good long while without a balancer, and some require it every charge.
Not that any of us ever observed the supposedly memory effect in any of our flight or transmitter
NiMh batteries (it did show up on cell phones, but not our airplanes), no LiPo battery has a
memory of any kind. And while it took a few flights for NiMh batteries to break in, LiPo
batteries require no break in of any kind, just go ahead and use them. New LiPo batteries are
almost always shipped at half charge. Let me repeat that, there was NEVER any memory to
NiMh batteries as used in an airplane, and LiPos require no break in at all.
For a worthwhile deal on a charger check the web site of Neumotors out of San Diego
California. The charger offered by the former F5B world champion is exactly what you need.
The owner in his special deals section offers perfectly good, if slightly behind the times LiPos at
a bargain price that are just right for any beginners airplane. Let the experienced pilots go for
the high discharge rate and long life LiPos, for you as a beginner crashing sets the limit on the
batteries life. I don’t often recommend going cheap, but batteries is one place a beginner
should.
Even if you have to discard/replace some of the included components with the Multiplex Easy
Star Package, it is still the most economical way to get started if you are starting with nothing.
A goal of Hitek was to deliver a complete system for a minimal of cash, they hit it exactly right.
It attracts beginners, who worry that their wife might discover the money that disappeared, and
check it out, it flies. Never before was so much flight entertainment for so little outlay possible.
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The market for chargers and batteries is constantly changing. Keep in mind that the charger
makes every flight. Modern equipment is so much better then those from even a few years
before that the purchase of a used charger more then two years old is not worthwhile.
Do not let yourself be advised on equipment by model auto drivers, the requirements on their
equipment are much different then ours. The second and third most common reason an electric
airplane won’t fly is trying to use used and new model auto parts. Although proficient with their
own equipment for their purposes, power-plant wise the auto people are way behind the times,
most of them still use heavy NiMh batteries and antique brushed motors! It has to do with that
the minimum requirements for flight are much higher then for a car. The model auto drivers give
full ampere only for a few seconds, we may use it for minutes at a time. Extra weight doesn’t
make much difference to a model auto, it’s a big issue with flight. All model autos have a gear
drive to match the motor to the load ect.
Batteries: this section was updated for 2011
By the start of 2010 NiMh batteries to power the flight motor have all but disappeared from the
scene. A few of us have NiMh flight packs laying around, they are still used to fly airplanes
specifically configured for them, but as the NiMh motor batteries and the airplanes that fit them
give out, we are not replacing them.
For a very few of us we are powering the flight electronics separately from the motor controllers
BEC, as a beginner you don’t want that complexity. For now, most of the airborne equipment
is still based on the voltages we used with Nickel chemistry i.e. 4.8 volts (4 NiMh cells was/is
98% of what is used and standard for almost all motor controllers Battery Eliminator Circuit i.e
the on board power supply) or 6 volts (servos work a little better, but few people ever flew with
five 1.2 volt NiMh cells), but, the manufacturers are converting everything, receiver, servos
and transmitter included, over to directly use 2S LiPo voltage of about 7 volts. So, you
probably still have NiMh batteries in your transmitter, and need to be able to charge them, but
for the motivation of you airframe LiPo is currently the chemistry of choice.
For now a majority of the transmitters in circulation still use NiMh batteries. Although a simple
transformer type charger will function to charge the NiMh batteries in your transmitter, it’s not
all that effective in that it takes the day at home plugged into the wall, and the charge is not in
conformance with the changing over use and temperature requirements of the batteries
themselves. As soon as you can afford it get a cord that will connect the transmitters charging
port to your charger. That five or ten bucks for the cable is worth it at the airfield and less then
the cost of a single drive back to the house when the transmitter unexpectedly goes flat. I charge
my 2200 mAh AA size NiMh charger batteries at 1 amp. For now all available multi function
chargers can still charge NiMh batteries. I have no idea how long the batteries in a transmitter
should last, I am still using some 600 mAh ones I bought back in 1997, after a couple of
thousand flights they still power my almost as old Hitek AM 3 channel for about 3 hours just
fine.
The most common way to ruin a LiPo battery is by crashing the plane carrying it, the second
most common is charging it wrong, the third is by attaching the connectors in a way that shorts
11
them out. That seemingly innocent spark blows a short in the battery that either ruins it right
then and there, or, creates an internal short. An internally shorted LiPo battery that is not
constantly recharged eventually runs itself down until the chemistry self destructs. The most
common ways to create a battery short is using a side bit cutter to remove both leads of an
existing connector (it simultaneously cuts through and shorts out the leads) and not first
soldering one wire to the connector and insulating it BEFORE going on to the second. Those
wires should be the same length and dangle into each other, that is why the manufacturers ship
them with the ends covered.
And every once in a while you are concentrating so hard on soldering, that you forget and
reverse the polarity of leads. Connecting a motor controller with reversed polarity almost, but
not quite, instantly destroy the motor controler. The electronics are ruined in a time on the order
of 10 to the minus 12 seconds, which is about the time it takes light to travel across the room.
By the time you see or smell the smoke it has already happened. Don’t bother asking the
manufacturer to repair it, buying a new one is cheaper.
There is another common way to ruin a LiPo, by using it half charged on a motor controller that
automatically senses if it is connected to NiMh or LiPo chemistry, or one that calculated the
allowable voltage drop as a percentage of the initial voltage. There are two ways for the
controler to recognize what kind of battery it is connected to; By sensing the voltage on
connection (easy and therefore inexpensive to manufacturer), and by being set (programmed)
forthe battery chemistry. Particularly in the case of 2S LiPos, that voltage is very close to NiMh
and the controler may let the voltage fall to what is ok for NiMh, which ruins the chemistry of a
LiPo, or, you connect a LiPo that is not completely charged and it lets the voltage drop to a
preselected low, which is too low, and wrecks the LiPo. If at all possible always connect a
LiPo fully charged. For a beginner without help the programming of which battery type is
confusing, fortunately most controllers now on the market are pre-set for LiPo chemistry. If in
doubt at the time of purchase get somebody who knows what they are doing to verify the
settings. And do not fly with a half charged LiPo battery until you have enough experience to
know when that is ok.
Where this sneaks up on you is that the battery capacities now allow long flights, so you land
and disconnect the battery half way through it’s normal capacity. When you reconnect the LiPo
the controler senses the new lower voltage of the partially discharged LiPo and sets the lower
limit based on the now lower voltage, and it’s too low. During the flight the power falls off and
in getting back to the landing the battery is over discharged to self destruction.
The capacity of a battery is... If you discharged a battery at a slow rate the amount it would
provide into a load is about equal to the rating in mAh. That mAh stands for mili (one
thousands) Amp hour. Accordingly a 2000 mAh rated LiPo battery would supply 2 amps into a
load for one hour. It’s a quite a bit more complicated that that, don’t worry about it for now.
There are two types of C values for LiPos, the discharge rate and the charge rate. The
origination of this type of rating was for how much current a LiPo battery can supply. If a 2000
mAh battery is rated at 25C, that means it can sustain 50 amps for at least a little while.
Sometimes they give dual discharge ratings such as 25/50. That means it can supply 100 amps
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for 15 seconds and 50 amps for minutes. That higher value (and often the lower one too) is often
overrated! And, recently as low internal resistance batteries suited for flight became more
available, the charge rate is also given in C. For the 1C that we started with (and therefore
didn’t bother to specify) that meant a 2000 mAh battery was to be recharged at a maximum of 2
amps. Recently 2, 3 and 5 C charging rate batteries have become available. In which case a 2C
2000 mAh battery could be charged at 4 amps, 6 amps or 10 amps respectively. At 1C a 2000
mAh battery takes a little over an hour to charge at 1C or 2 amps. The higher C ratings are great
if you need them, but they cost more. Crashing sets the durability of batteries among beginners,
when you chose your first LiPos, as a beginner the lower C ratings are just fine. Nowadays all
but the cheapest of LiPo batteries lasts at least fifty flights, if you don’t slam the airplane
carrying it into something solid first.
To review: If you have a 2000 mAh LiPo Battery rated as 2C/25C it may be charged at 4 amps
and deliver for fifteen seconds up to 50 amps. If in doubt, charge a little slower and watch those
output peaks. In the competition to sell their product many of the lower cost products (which are
preferable for you as a beginner) are overrated as to their discharge rates. If you use Multiplex
airframes the most expensive single flight components as you stand there at the flying field are
your batteries.
When we started with LiPos they had discharge ratings in the 3C range. At 3C a 2000 mAh LiPo
could output 6 amps. In order to get enough discharge capacity we often had to run them
together (parallel) and to get enough voltage we still have to add them (series). So a 2000 mAh
with the description of 2S2P stood for two 1000 mAh LiPo cells in series and two LiPos cell
pairs in parallel for a total of four individual battery cells composing the battery. Other then a
very few competition machines (typically the $3000 F3A competition aerobatics fliers) nobody
now needs to run the LiPo batteries in parallel to get the amperage capacity up, the xSxP has
now been shortened to just xS.
LiPo Batteries don’t Last Forever
By the very nature of their chemistry LiPo batteries lose a little capacity every year. If you leave
them fully charged on the shelf, unused, they will lose about 5% capacity per year. If you
nearly fully discharge them, and leave them on the shelf unused they lose about 4% per year. If
they are half way between fully charged and fully discharged they lose the least capacity or about
3% per year. It would take controlled testing done on some rather expensive machinery to find
the difference between 3% and 5% per year. Don’t worry about it. For a while the magazines
had feature articles about how to precisely run the batteries down. It might have to do with a
practice the car people had of always running their NiCad batteries down in the thought that they
developed a memory. We in airplanes used to laugh at them about it. As a beginner you need
not care, other then to be careful what you pay for old stock and used batteries. In careful
testing almost all new batteries have slightly less capacity then as labeled, the difference gets
greater over time, and LiPos are still great, better then anything we ever dreamed of.
13
Easy Star Examples: The german text was not updated for 2009. The American text was
brought into conformance with currently available materials for 2011
Costs are as of November 2009, all parts new in California including tax with me knowing
where to get a best price while the walk in Hobby Shop stays in business. The most complicated
part is the power set up, I can only provide likely examples. All setups include Hiteck HS-82
servo(s) (twenty dollars each if not bought as part of a new radio), a Hiteck 3 channel FM radio
(pay the difference and swap the included two HS-55s for HS-81s when you buy the radio), (8)
rechargeable NiMh AA size batteries plus a cable to connect the transmitter to the charger. Add
$20 for the much better Spektrum Radio. The wings were fitted out with magnets to hold them
together, all the connectors (Deans) were for use in an airplane and there was some selected
reinforcement with fiberglass tape. A hundred and eight dollars gets you a first rate charger if
you know where to get it, otherwise a hundred and thirty for a more average purchase, that is
about the upper limit on what a beginner sport flier needs to spend on a battery charger. We
bought new front line 2C/30C batteries that can charge in twenty minutes, older lower capacity
ones can perform just fine even if they take longer to charge. We had a wattmeter to determine
how the then unknown to us combinations worked. In other words complete modern equipment
bought new and set up by somebody that knew what he was doing.
I have seen airplanes fitted out with twelve dollar brushless motors, seventeen dollar controllers
and five dollar servos fly fine, for a while. Those were internet prices and you have to be able to
cope with things that don’t always work, I have reservations about both the reliability and the
durability of stuff that cheap. My one personal experience at the bottom end of the market was
with a Euro 130 complete airplane system that was almost a copy of the Easy Star. The servos
output shafts teeth wore off in two hours, the radio lasted fifty flights, the charger eighty, the
motor speed control was electrically noisy and to save on costs they left out a couple of FETs so
that it did not have the rated amperage on the sticker, the plane was a slug with a Speed 400 on
2S Lipos (but then, so is the Easy Star at 30 watts) and even after adding more power (the speed
controler had to be replaced) it did not fly all that well. An Easy Star can easily handle much
more weight, this one could not. It was made of good foam though and for the teenager I gave it
to (after flight 93), Euro 5 replacement servos replaced speed controler and all, it was a big
improvement over his all inclusive Euro 100 system.
Part of the reason for buying such a cheap system was that it was complete to include a cable so
the transmitter could be connected to a home computer for flying simulators. Since then the
program FMS (which can be downloaded from the Internet for free) is currently available with a
simple transmitter like controler for $28, any computer can run it. For a big jump up you can
buy an amazingly good simulator including a controler that feels just like an inexpensive 4
channel transmitter for $53. A full range simulator costs $108, the really good ones cost $250,
the computer requirements are proportional to the price. See the following warning about
forgetting you have a family and a job.. Airplanes can be assembled from cheap parts and fly
fine.
There isn’t much on the airframe itself to adjust the price. Almost nobody ever sells their Easy
Star intact although if you find one of the other Multiplex airplanes for sale used they can be a
good deal. Mini Mags and Easy Glider Electrics often outlast their first owners interest. If you
14
have to, an Easy Star is an ok place for cheap servos. It is impossible to advise you about every
possible selection, therefore, here are some representative examples.
If you have to keep it cheap:
An Easy Star will fly on what was the stock setup of six NiMh flight batteries and a Speed 400.
Many pilots have learned their stuff with them. But you are much more likely to crash with this,
on the minimum lower limit thrust, then if you have more power. If we rate the crash frequency
of an Easy Star with 100 watts-out as one, then trying to fly with the stock Speed 400 on 2S
LiPo batteries means crashing about ten times as often. However, too much power can be a
problem for beginners too, my usual personal 250 watts-out set up has a factor of three times as
many crashes in the hands of raw beginners as the more aproiate 80 to 150 watts-out packages.
Included with the Easy Star complete package setup was an 8 ampere motor speed controler that
is maxed out with the 6 volt Speed 400 on 2S Lipos (or 6 cell NiMh batteries) and the 5 X 5
black plastic propeller. The Multiplex basic motor controllers have the advantage that they will
automatically accept either Lipo or NiMh batteries with no need for settings by the user. With
2S Lipos or small 7 small cell NiMh the supplied Speed 400 motor is good for at least a hundred
flights. Flights where you have to carefully balance on minimal thrust and only fly on days with
almost no wind near sea level.
A 6 Volt Speed 400 on full throttle with 3S Lipos will last up to one minute before burning up.
Only a very few pilots with the required self control to never give full amps to a Speed 400 (or
just for a few seconds, one limited his amperage with the computer in his transmitter) have been
able to use the Speed 400 on 3S Lipos, but all of them already were experienced pilots already.
I tried higher voltage Speed 400s, don’t waste the effort. The 8 amp controller burns up first if
you try 3S LiPos on the standard 6 Volt Speed 400.
If you get the slightly more expensive 16 amp brushed motor controller you can run a more
powerful brushed motor. Substitute a long case 6 Volt Speed 400 or 480 (better) for the with the
kit supplied Speed 400. The motor is still limited to about ten amps for a 70 watts-in and 40
watts-out though. Or use (6) Sub C size batteries (the size cars use) in the capacity from 2500
mAh to 4500 mAh and a 6 X 4 APC prop. If you have to this also works with the black
Multiplex propeller. Watch the motors output shaft diameter when selecting the propeller hub,
it me be 2.3 mm or 3.0 mm or 3.2mm. This is heavier then other combinations, it will supply
from (12) minutes on up of continuous motor run time for about fourty flights before the motor
wears out. Because of the additional weight it has to fly and land a little faster, so there is more
chance of damage on hitting something, the extra weight becomes a benefit in the form of
easier control as the wind gets above eight miles an hour. At this weight you need to double the
width of the rudder.
Do not use this combination unless you already own a working brushed motor speed control
(maybe available from a club member used at a nominal cost) and can get the motor for less then
ten dollars as it is otherwise more cost effective when buying new stuff to go straight to
brushless combinations. The easiest source of big NiMh batteries is a new car pack reconfigured
to three above and three below. Just don’t forget to replace that airplane killer Tamia connector
15
with something reliable, like those from Deans. NiMh batteries and the brushed motor both
require a couple of runs to break in, let them run once on the bench.
The set up is only cost effective if you can get the motor, controller and prop for not more then
twenty dollars, the two battery(s) cost new about $25 each and you reconfiguring them yourself.
In that case the savings works out to about eighty dollars, not including that the motor only lasts
about as long as a beginner with his first airframe. This combination also works with 2S Lipos,
many recent brushed motor controllers have the low voltage cut off required for Lipos, older
ones don’t. Where it really shines though is if you can shave another hundred bucks off by
getting by with an older NiMh only charger, and maybe the batteries too, for nearly free. If
that’s what you can afford (that could be as little as $150- for a fitted out airframe not including
radio and charger), it won’t be as exhilarating or as durable as a brushless setup, but it’s still
fun. By 2010 even I quit building this combination. By then the improved costs and availability
of LiPo batteries and brushless motors rendered this low performance combination pointless.
If money is that tight try buying somebody’s used setup and putting it into a new airframe or
experiment with cheap Internet stuff. See below, I am a master scrounger, you are going to
need some help if you buy used or cheap internet stuff.
Still the best:
Use a (28) mm outside diameter inrunner that weighs about (75) grams) with a kV of between
2500 and 3000. It should cost from $44- on up, $75- being a best price/performance choice
(well matched combinations go to 84% estimated efficiency), the ultimate is a Neumotors 1105
(even on 2S they hit 90% efficiency and any two perform the same, not so for the cheap stuff,
they can get up to 94% real demonstrable efficiency) for $120. You get what you pay for, the
cheaper stuff is less effective and has problems, or soon develops them. That inexpensive motor
has junk bearings, sloppy machining, soft materials that don’t hold up, a percentage of them
vibrate even when new, they have relatively poor efficiency (particularly at part amps, they are
still a vast improvement over brushed motors), they may not be the specifications listed on the
box so if you try to set it up without a way of determining how much power it is drawing
everything burns up, ect. In an Easy Star the better motors are well justified as they often
outlast the first two or three airframes.
With the older high internal resistance Lipo Batteries a (25) amp controller worked with this
combination on 3S Lipos, with modern batteries better use a (35) amp controller on 3S Lipos,
the best current choice is the Castle Creations simple and inexpensive one. The lower kV works
well with a 6 X 4 APC prop, the higher kV needs a 6 X 3 or 5.5 X 4.5 prop, which for reasons
nobody understands are not currently available. This is about the only combination where 2S
Lipos may be used for learning (or 8 cell AA NiMh batteries, or a seven cell car battery
reconfigured to fit) followed by a switch to 3S Lipos for more then double the power.
Usually substituting 2S Lipos for 3S Lipos without changing the prop just turns the airplane into
a slug. It’s an X squared thing. 2 squared is 4, 3 squared is 9. 9 is more then twice 4, and in
reality going from 2 Lipo cells to 3 is even more power gain then that.
16
Not worth doing;
Up to about 2010 I recommended not bothering to coax an innrunner into an Easy Star. To me,
just because somebody else cobbled a motor mount in place didn’t mean it’s was worth doing.
The 15 amp on 3S innrunner set up Multiplex offers for the Easy Star (or Mini Mag) is about
ideal for a beginner. If you just have to use your outrunner set up try a Multiplex Easy Glider
Electric or Mini Mag instead. Or trade what you have for what you need. But, outrunners are
now 90% of what is available, and they now have pre-made plugs that allow the use of 40 to 50
gram outrunners that take up to 20 amps and it works out fine. If you have to use an outrunner
combination in an Easy Star watch out that it moves the center of gravity rearwards and too
many beginners don’t know enough to add weight in the nose or use a heavier battery. But why
not just do it right and put an inrunner in your Easy Star.
A preferred “learner” combination:
Towards the end of 2009 I built an Easy Star (I think it was the ninth) for a friend’s ten year old
son to learn to fly on. Although the combination was not as powerful as his father and I would
have liked for ourselves, it was easily available, a little less expensive then full power and
suited his son well.
Despite the local dealers personal dislike of them, we used a Hitek (3) channel system with the
throttle in back. I like these little Hiteck radios. Of I think fifteen that I have had, two
transmitters failed early, the rest lasted a long time. Critical for this application, it fits in child
size hands. We could set the motor for enough power for a slight climb and let the youngster
concentrate on just the one stick. We selected decent rechargeable batteries for the transmitter
(Sanyo Enelopes are the best), the cheap one time use batteries are a waste of money (unless you
just have to get in the air now and that’s all there is). Ask the dealer to help you getting a cable
so you can charge the transmitter with the field battery charger. That plug into wall current
transformer at home isn’t much help at the flying field when the transmitter battery goes dead.
The NiMh chemistry of the transmitters batteries requires a few tries to break in, the first
charges go dead quickly. With modern 2000 mAh Sanyo Enelopes at $2 each you have at least
five hours of transmitter time. The Hitek FM receiver is fine as long as there aren’t too many
other FM transmitters going right next to you. Please try to remember the warning to NOT point
the transmitters antenna at the airplane as if there were some kind of invisible line from it the
airplane. If you get a FM one used and need an improvement, or just another receiver for
another airplane, get the one from Berg by Castle Creations. For adult hands get a modern Giga
Hertz frequency hopping system.
The limited power of this setup was a benefit too, the sudden application of full throttle (250)
watts output at the prop we originally planned for his father can unexpectedly shove the plane
around and slam it into things. The motor, acquired used with almost no run time, was intended
for use in a helicopter on three or four cell Lipos, it had a kV of 3200. On a 6 X 4 APC prop it
drew fourteen amps on a 2S 2200 mAh Lipo for an output of about eighty watts to the propeller.
Commonly available inruners with kVs up to 3500 work fine on 2S Lipos. We had to add
weight to the batteries to get it to balance. You might as well stick with an (17) amp controller
17
for this power set up as going to a 3S Lipo battery required a 5 X 3 propeller and was not really
effective, the too fast speed of the propeller just went up in mostly noise.
This motor was an odd one that has started showing up, an outrunner in a case. An inrunner is
more efficient then an outrunner if they are turning at the same kV, provided it matches the
propellers requirements, and weighs about ten percent less too. The rock over where the greater
efficiency from an outrunner turning the propeller over slow verses running an inrunner at the
lower end of their scale is, with the typical low cost 28 mm diameter setups on 2S and 3S Lipos,
a kV of around 2200. With kVs under 2000 get an outrunner, above 2500 get an inrunner. If
you find yourself flying next to me and wonder why my airplane performs so much better then
yours, it’s partly because I am the pilot, and because my airplane is using an inrunner. My
Mini Mag is fitted with a 1700 kV 80 gram inrunner on 3S with an 7 X 4 folding prop. I can
climb out of sight in a count of 25, it’s all the little airplane can really use. As noted elsewhere,
out of courtesy they call me a fool, instead of a smart ... The above kVs only apply to the above
size motors which are what usually fit in an Easy Star, Twin Star or Mini Mag and then only
between 7 and 12 volts. Transmissions with modern brushless motors are not for beginners. So
this one with a kV of 3200 was clearly in the wrong range from a technical sense. But, the
slight extra weight and lower efficiency were less important then that I had it, since it was in a
case we could glue it right in, even if it’s wrong the market right now is convinced that
outrunners are just the greatest, I scored it virtually new and cheap, the friend wanted
something for his son...
The friend, an excellent pilot with loads of flying wing experience, just could not be convinced
that we had a learning airplane for his son that was not agile enough for him to land behind the
shop where we often flew flying wings and routinely hit high voltage lines. Hitting the power
lines started as just an accident, we used to make a sport of how many we could hit (the record is
five out of six) and still continue the flight. At first look it’s an unlikely place to fly, a steep
rocky hill covered with brush and trees overlooking an industrial park, a fifty foot wide alley to
land in and some really neat unpredictable winds around the buildings, but the new materials
allow it. The AMA (The American Model Association, the source of insurance) doesn’t. It’s
funny sometimes how such a simple toy can inspire so much excitement. And then there was the
time a hyped up millionaire sports care owner who normally had full command of his
surroundings, was dismayed, and ultimately calmed down, when he realized that his equally
intelligent mechanic and engineer friend were going to go fly airplanes out back and he could
come along and participate or not, we weren’t going to work on restoring his old Ferrari just
then. In a shop full of high dollar sports cars with a research MD in attendance we made the
maiden flights.
This combination isn’t the most efficient or longest duration one, flights at continuous full amps
last about fifteen minutes. He cracked the wing on the second landing by hitting a parked van,
again. It was easily glued with CA back together, replacements wings are readily available for
$25 and take only a minute with glue to assemble them, the dent in the wing didn’t seem to
make much difference. After that he used the plane as intended. That first hit would have
destroyed any other material and were the motor in front, that too. There were no marks on the
van to show the plane strikes.
18
His son thinks the plane is just great, the transmitter fits in his hands, it is fun to balance on
gentle winds and thermals and it is easy to land. His father accepted that the times had moved
on, I wasn’t going to assemble the same old combination if the goal was for him to teach his son
flying, at least not this time. The airplane soon had (70) flights with no additional repairs to it.
With two of the modern fast charge Lipo batteries and the ability to charge from the car he can
stay flying as long as he feels like it. His sons neck gets sore from flying it so much.
We do however miss the flying wings though and in due time (when Multiplex makes the Xeno
flying wing available in the USA) he will be buzzing around with them again. The new unused
$220- Spektrum Ds6 radio (see above, you find yourself in a hobby store) will be used with
other airplanes. His son caught on quickly and didn’t need the capability to hook to another
radio anyway. It’s usually the older pilots that need the help of another pilot standing by with a
second radio to override the beginners radio. And then there was the aging former F4-Phantom
weapon’s officer (he needed glasses and he refused to admit it) that just didn’t like being on a
harness with a nurd...
In the end we had we gone straight to this set up the total net cost was, as of November 2009,
about $470-. That was with everything bought new, but not including insurance. For that he
has a hand built Easy Star (I do a better job of gluing them together then factory and didn’t have
to cut the Speed 400 motor out or run the third wire on the outside for the modern motor), a
worthwhile charger with an integrated Lipo balancer, two 2C/35C 2S1P Lipos (2100 and 1800
mAh) that can be recharged in twenty minutes, an 18 amp reliable speed controller, a quality
brushless motor that won’t wear out, and a 3 channel FM 72 MHz radio with rechargeable
batteries and a charging cable. A set of replacement wings cost $25. A set of wings fitted with
ailerons including extension cables, “Y” harness and an extended spar cost $100.
It’s worth it! You can’t go bowling, or drink 40 ouncers at the beach for what this set up costs
per hour of flight. We had a great time with flying wings, but these are the most satisfying “just
fly the thing” planes ever made available.
Getting the Servos to work:
The holes in the control horns supplied with the Hiteck HS-81s do not match the wires used with
the Easy Star perfectly. I chose nominal travel on the elevator with no slop by cutting down the
round output horn. Because the servo/radio combination does not center the servo output at the
neutral setting of the transmitters trim I set it forward (relative to the airplane) of center so that
there is a little more up then down at the elevator with the trim set at neutral. For the rudder I
wanted more travel, so I used the supplied “X” (cut the three extra arms off) and accepted some
slop from the oversize hole. Beginners often forget to glue the servos in. Getting the perfect
servo horns would have required another trip to the Hobby Store and most likely going through
the boxes to find a more suitable servo that included an arm that could be re-drilled. Almost
nobody notices the slight free play at the center of the ruder travel on an Easy Star anyway.
Someday when you go to higher performance airplanes getting things slop free will be very
important, but not with the airplanes described here. If you buy the complete setup from
Multiplex the servo arms match the control wires.
19
I ruined a $25- servo in a foam motor sail plane (where it could not afterwards be accessed) by
using to much CA glue. No liquid went in to the servo, but the fumes condensed in the gears. I
now use Goop glue for all servos. Run the servos on the bench a few times and make sure you
center them correctly before gluing them in. You get one easy try to assemble a foam airplane.
Break in of Lipo batteries and Brushless Motors:
Contrary to anything else you may have heard, LiPo batteries require no break in of any kind.
As the owner of Thunder XXX put it “I got so tired of telling that to people who didn’t want to
believe it, that I finally told them to go gentle the first few flights”.
The same almost applies to modern brushless motors, they have no break in requirements, but if
it makes you feel better run a battery load through at low amps first. What does happen is that
the skirts to keep dirt out of the bearings and the lubricant in wear. Racing bearings don’t have
much free play in the bearings, others do. Cheap motors have cheap bearings, that quickly wear
out.
Motor controller capacity:
There are so many variables in the component parts that you really need to have access to a
means of measuring how many amps a set up uses. The highest demand on the regulator is when
the load is too high at part throttle. Creeping up on a combination by starting low just burns out
that regulator if it’s has too small a capacity. I use an older 40/55 amp speed control that was
made before Lipos and their different from NiMh batteries low voltage cut off to run in new
combinations, I paid $12 used for it.
A usable watt meter costs $65-, if you continue with this hobby it will be in continuous use.
Measuring the current and voltage is required every time ANYTHING, prop (even a different
brand with the same marked diameter and pitch), lower internal resistance batteries, a different
motor ect. is changed. It can also identify a servo drawing continuous power because it is either
hanging up or defective. For those of you starting out, get help at either the flying field, or at
the Hobby Shop. You are going to get help aren’t you?
We found out the hard way with brushed motors that it was cheaper to get an oversize controller
then to splatter the whole airplane from using one that we thought was big enough. As the
motors wore in and out together with variable battery performance the limits of the controllers
were unknowingly exceeded. With the modern brushless controllers that no longer appears to be
the case. Get it set up right and it will fly until something, like the bearings in a cheap motor
wear out, or you change to lower internal resistance (i.e. higher C rated) batteries, changes.
But, they now give the capacity of the on the motor controller power supply (BEC battery
eliminator circuit) in amps. An Easy Star can fly fine with a 1 amp BEC, 2 amps is better.
Beginners tend to want to fly with things bent and binding, that drives up the loads on the servos
and BEC.
Somehow 6 X 5 and 6 X 6 propellers don’t work in an Easy Star, just too much mismatch
between propeller and airframe speeds.
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Lately I am flying a 1.2 meter all fiberglassed over foam motor sail plane on an inexpensive 40
gram outrunner. The motor was miss-marked in that it should have had a kV of 2200 to run a
medium prop at moderate rpm on a 2S LiPo in a slow flyer, and actually has a kV of about
3000. On a carbon fiber reinforced 6 X 3 folding propeller from Aero-Naut and 3S 2000 mAh
Lipo it pulls (26) amps at (10.4) volts (that is measured running on the work bench in front of the
motor controller before loosing 0.6 volt going through the power transistors. That is the
minimum loss which only applies with the amp flow at maximum), with a Castle Creations
economical (18) amp controller. As it turns out 26 amps is the limit the controler will flow, if
left to take as much as charge as it would the motor would draw about 35 amps, for the quarter
of a minute before it went up in smoke. It has good air circulation, the amps the motor draws go
down in the air as the prop is cutting into air that is moving and not accelerating it from standstill
and after fifteen seconds the battery voltage (and with it the amps), start to drop off. By not
running the motor for more then the five to fifteen seconds it takes to climb four hundred to a
thousand feet up out of the every one to three minutes it takes to glide back down for the
typically 45 minutes flight are what lets it work.
That kind of performance is addictive! Instead of the usual $32- the miss-wound motors only
cost $18- new, but the bearings don’t last very long, so far forty flights. A durable modern
alternative of an Razor brand inrunner with a transmission costs $132 plus a larger prop (10 X 6)
at $30. A more practical if less efficient set up would be a $80 German designed made in China
(brand Hacker) outrunner plus a bigger prop, they don’t wear out and perform better then the
$32- ones. Either one is better then the Jamara, but it’s already a rocket ship so... Hyperion
motors are about half the price of Hackers and only a little less in performance. You can’t go
wrong with equipment from Multiplex/Hitek if they meet your requirements. We in San Diego
like Scorpion band motors. I check power draw every twenty flights as you can’t feel the rear
bearing going bad by flipping it through.
Let’s examine that again, 60 flights. If I make three 45 minute flights per session that is 20
sessions. Twenty times an afternoon spent with my gaze in the sky free from other cares. In
case you were wondering, the best place to land that airplane in a stiff breeze is a field of
standing wheat.
If you just have to, the foam under where the motor usually goes in an Easy Star can be cut out
to secure an approximately ½ inch by ½ inch by 3 inches long piece of hard wood (not balsa)
glued in to mount an outrunner motor. Despite the hour long hassle of adding in the wood for
the mount and problems that the motor mount tears lose over impacts, a 45 gram 28 mm
outrunner in 1500 kV at 3S would perform fine. In 3000 kV the motor would, with the longer
run times in an Easy Star, burn up on 3S and even on 2S needs a bigger propeller then the 6 inch
diameter the Easy Star can use. The 3000 kV inrunner motor combination offered by Multiplex
is a fine one for an Easy Star.
Beware that the BEC (Battery Eliminator Circuit) of the motor control which supplies the
receiver and servos with power has limits. An Easy Star with two (18) gram servos needs 2
amps. I shredded a Twin Star on four HS 81 (18 ) gram servos with a camera taped to it looking
for a lost Easy Star in the forest canopy by not paying attention to the controllers limitations on
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the amount of power it could supply was for two servos at the voltage I was running the motors.
What luck that the wreckage landed just ten feet from the trail, I finally found it after three hours
looking by hearing the servos chattering. It had 26 flights on it, everything but the foam (and
the motors that eventually wore out) is still flying in another Twin Star that now has 420 flights
on it.
I recently equipped a Sturmovik, which can take the same power combinations as a Mini Mag or
Twin Star, with a 62 gram outrunner (bought used of course) a small 12/15 amp controller (used)
and went to 4S Lipos (new). The capacity of that BEC varies with the input voltage. At 2S it
can power four servos (standard size) at 3S it can power three servos, at 4S only two servos
(three in the form of elevator and two aileron servos, all small is equal to two standard servos)
may be run. The biggest prop I dared run was a 11 X 8 Graupner CAM, on 3S it delivered 65
watts, on 4S 120 watts. I went to a different much more expensive controller (an obsoleted
version being sold off) for 5S, with a smaller prop it puts out 180 watts. The manufacturer rates
the motor at 70 watts-in. It’s my motor, I can do what I want to with it.
Easy Star Aelerons:
For the ten year olds father, a second set of Easy Star wings was constructed with aelerons.
Although eighteen gram HS-82s (the same as in the fuselage) would work fine, they represent
an unnecessary expense, size and weight, eight gram HS-55s work well here.
A one inch to one and a quarter inch wide section of the wing is removed starting eight inches
out from the fuselage for eight inches (alternately, start from where the wing tapers up and come
in eight inches, further out is better), beveled, and reattached with packing tape heat shrunk on.
Do the tape top side first, then fold the aileron back and attach a second layer underneath. If you
don’t have experience covering with packing tape this will take a few tries to get right. As
simple as it seems, pilots accustomed to traditional materials do not recognize that the tape
underneath is all that prevents the aileron from levering up and off of a single side layer, and
then they rave about how tape hinges don’t work. See above, about eighty airplanes, all but
three had taped hinges. Even my 120 mph foam hotliner. The servos are glued into a recess cut
in the wing, put a layer of tape over them afterwards to additionally secure them.
The aileron servo control wires are installed in slots in the wing and trail out into the fuselage. It
is possible to just tape them under the wing, but the performance suffers more then the gain of
adding the control surfaces. For durability, the foam at the control horns needs a layer of balsa
or other reinforcement, I use fiberglass.
The aelerons really must have about twice as much up travel as down. That unequal travel is
called differential. That is most easily achieved by, with the servo arms underneath the wing,
having the control arms set one or two teeth behind being at a right angle to the control rod. That
works out to about 15 degrees. Take note that inexpensive servos used with a simple radio do
not necessarily center at right angles to their case or each other, you may need to align them as a
pair with the transmitters trim. The higher quality servos and more elaborate radios allow
individual centering and tuning of the travel of each servo along with other benefits, if you are
sophisticated enough to not be overwhelmed by the adjustments. The control surface is more
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effective at pushing a wing down then up, the additional drag on the up aileron serves to get the
down side wing trailing into the inside into the turn. For more detailed information get an
advanced text on aerodynamics, not the ones available at hobby sources, this gets into
aeronautical engineering.
Combustion pilots usually refuse to believe in setting the ailerons up asymmetrically (and not
running the aileron all the way to the wing root), and then claim that foam airplanes don’t fly
right. One of the advantages of electric motors is being able to stop and start them in the air,
folding propellers make that even better. Fuel burners with their blunt high drag front ends and
constantly shaking motors (that they hope don’t quit in flight) wound up with some additional air
flow over both the inside of the wings and the tail that had been inadvertently figured in. Have
them look at an airliner or private plane and report back where the ailerons are on them, or
check with the thermal glider pilots and slope soarers, differential is standard for them. Long
thin flat wings won’t easily turn on just ailerons without differential, the physics were
established before mankind knew how to build a wing.
An Easy Star set up with just ailerons is more agile then with just the ruder, but not a whole lot,
those cut outs in the wing add drag, with ailerons they don’t glide quite as well. In the hands of
a beginner the wing tips and the whole wings take a beating. Ailerons can take advantage of a
more elaborate radio to work as either flaps or landing brakes. There isn’t much advantage in
flight to having both rudder and ailerons, other then when landing in a restrictive space (or
flying between trees inverted), some people just like having both. In a cross wind landing with
ruder only the plane can be made to go straight down the runway, but to level the wings and
touch down it has to be slewed away from the wind, and into the fence. With ailerons the wings
can be held level, but you have to angle onto the runway, without hitting the fence first. Take
your pick, don’t make cross wind landings until you know how to handle the airplane.
Beginners are better off with just one lever to concentrate on. There may be a slight advantage
to ruder and elevator for older and non video game playing pilots and a slight advantage to the
youngsters and gamers with younger ailerons and elevator.
However, the airfoil cast into the Easy Star wings and the general flexibility of the whole
airplane precludes elegant aerobatics. If the plane is being assembled new with just ailerons the
white tube down the side must still be installed as it is structurally needed for the airframe.
Making the wing last:
Don’t forget that the mechanical lock between the Easy Star’s wings begins to fail at about fifty
flights. It feels fine on the ground, they come apart in the air. Glue in some magnets (cover
them with a single layer of packing tape to hold them in place while the glue dries, do the wing
as a pair and with the magnets together so as the glue hardens they stay in alignment) or tape the
wings together.
If flown hard (and why not?) the original un-reinforced wings develop a “hinge” about where the
spar ends. Either a layer of fiberglass reinforced packing tape on the bottom of the wing going
the full length and lapping over the top an inch, a longer spar or just buying new wings are
solutions. Getting the tape to stick often requires first spraying the Elapor foam with glue, try
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the glue on a piece of scrap first as if the formulation includes acetone it may dissolve the foam.
The same precaution applies to glues. A covering iron’s heat not only massages out the wrinkles
in the tape, it also activates the tape’s glue for a better bond. Replacing the main spar with a
longer one is easier then fiber-glassing the bottom of the wing with ¾ to 1.5 ounce per square
yard fiberglass, although the glass improves the durability of the wing greatly.
During a period of being broke (will it ever end?) I just went ahead and flew an Easy Star until
the wings ends bent up 25 degrees, on each side. That went on for over fifty flights (it made for
great barrel rolls in twenty mile an hour winds, I have a blast with the gusts to thirty miles an
hour) until I reinforced the wings with tape and gave the whole setup to an eager young beginner
using a new Speed 480 on 6 big car NiMh cells set up. At first he had a way too cheap airplane
package (Euro 110, neither he or I couldn’t get it to fly, I finally concluded that the receiver,
transmitter and speed control were all junk, the styrofoam wing was wrecked by then) and then
he bought a way too expensive transmitter second (Euro 300, are you a programmer?). It flew
well, even if it looked like a somebody with no color sense had cobbled it together. I no longer
buy partially used cans of spray paint. It lasted fifty flights surround by vineyards looking out
over the Rhine River until he lost orientation and flew it through a tree at the end of a long dive.
All he was able to use from the first airplane was the 7 cell NiMh small cell battery, and with it
the Easy Star was so under-powered he soon left it at home anyway.
Unexpectedly, the fiberglass tubes offered as servo rods can easily be made slightly larger to fit
with just electrical tape and perform fine as an Easy Star wing spar. Carbon fiber is better
though. An additional rod glued inside the original Easy Star spar to extend it can be drilled into
the wing halves to about where they curve up for a nominal expense and effort. We had a pile of
used wings to learn on.
Keeping the cowl on:
The newest cowl hold downs work reliably until a motor is installed allowing speeds that
Multiplex as a company did not originally plan for, but the designers smile every day about. It
is easier to get the depth right if you install the upper parts in the cowl while the fuselage is sill in
halves. A couple of pairs of magnets on opposite sides work well to supplement the original
attachments, while you are at it if you are using a lot of amps add some additional cooling holes.
When the canopy of my Mini Mag flew off right in front of me to flutter down a hundred yards
away behind the first row of trees in a scrub forest on the Santa Ana River, I could never find it.
I know where it is to within a twenty yard wide search area, after looking ten times the cost of
torn clothing exceeded the value of the canopy. I had more investment in the whole airplane, I
haven’t climbed so many trees since I was a child. Try poking a traditional balsa and iron on
covering airplane with a twenty foot long stick while standing on a branch thirty feet above the
ground and see how long it lasts. So when I made a replacement canopy out of EPP, I used my
usual hold down for canopies, just a good grade of electrical tape. I wasn’t figuring on still
flying it four years and 285 flights later, see above, the shame of the club. And then there was
the time I had to crawl/swim over a hundred foot wide ten foot high pile of fallen giant cane to
recover an Easy Glider when the wind quit, and fell through to hang by my arm pits...
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How much power will fit:
The latest catalog from Multiplex USA acknowledges what the rest of us quickly demonstrated,
the output wattage of an Easy Star can easily be (300) watts. I recently flew an Easy Star
equipped with a Wattmeter verified 450 watts-input on a 6 X 3 propeller with flaps and ailerons.
The owner enjoyed being able to fiddle with the airplane without any great effort or expense (he
just left the additional servo cables dangle under the wing), it did not perform as well as my
“clean” 350 watt-input airplane. I only tried it once with a scale 4 bladed prop bought at an
airplane swap meet and an old brushed ducted fan motor, there might be some benefit from
running a three or four blade prop at lower speed.
Note that my power descriptions normally include the losses through the controller and factor in
the expected efficiency of the motor at it’s operation range from the virtual dyno (available on
the Internet), not the peak possible efficiency claimed by the manufacturer for advertising
purposes, for an estimated output wattage at the prop. I doubt if any airplane ever commercially
available is so easily and routinely equipped with so many times more power then it was
originally offered for.
Making your airplane visible:
Although it adds weight (a trivial amount for the Easy Star airframe), a simple contrasting layer
of ordinary spray paint makes it much easier to see the orientation of the airplane in the air, that
is even more important if there are other Easy Stars flying with you. Two common reasons for
crashing are not being able to tell which side of the airplane is up and not being able to decide
which airplane is yours. You have to blink sometime. I like to paint the vertical tail a bright
orange. When flown at long range which way the airplane is going is much more quickly
identified with that bright rear end. Yes, invisible air currents can turn the airplane around (in
all three axis) faster then you can think, see the following, get ready for surprises. Multiplex
offers an elapor primer if you want a really nice durable finish, but, as advised, do not fall in
love with your first couple of airplanes.
Glue:
I still like using Goop brand glue on Elapor (it weighs more then CA but has a little give), but
CA works almost as well and is easier to use. Available in Germany is a product called Beli
Zell, itself an expanding foam with a little solvent, that is just the greatest stuff for foam
airplanes ever. I will never use Shugo glue to assemble a foam airplane again, the solvent is too
aggressive and there is too little filler. The latest purpose products from Multiplex, or Beli Zell,
cost a little more then thick CA glue, and are worth it. Hot glue seems to work fine, at first.
But the bond ages and parts start working lose i.e. they just snap off with no warning, after about
six months.
My airplanes last longer and withstand crashes better then anybody else’s, they have to. I don’t
ever use hot glue. Foam is able to bend, adding in a crystalline rigid connection in the form of
cynoacralite glue joints is fine at the original attachment points, but for repairs out where the
airframe needs to flex it focuses the stresses to break the intersection of the adjacent foam cells
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to become a never ending repeating failure. One of the common places to break an Easy Star is
the where the fuselage front splits on a hard landing. The foam is now deformed, where as it
went together fine with CA, there is now an uneven gap. Try using Goop for repairs. When I
have the time I now fiberglass the whole front end of my Easy Stars and down the belly to about
three inches past the antenna tube. The same for the “handle” of the wing holder although fiber
glass reinforced tape, like we used to use for Zagies, works almost as well. The extra weight is
trivial, the trick is to use enough fiberglass to assist the foam, too much and all the load goes
into the fiberglass. For the non engineers in the group, loads do not go into the strongest part,
they go into the most rigid one.
Does something this simple and easy really work:
For pilots experienced with expensive material the performance is shocking. All it takes is a soft
push to get it flying, glide slowly to ant altitude over the airport, then give full ampere to climb
at 45 degrees to 400 feet in 9 seconds, pull back on the lever to quiet and hunt thermals, drift
slowly down, make a few loops, maybe slowly fly the length of the runway inverted and repeat
over and over for half an hour without landing. Without liquid fuel or the getting filthy with
castor oil, no maintenance, no having to carry a box of support stuff or hook up a battery to the
glow plug and flip the prop. Just put the wing in, install the battery and away it goes! Any
question about the viability of foam and electric power will be vanquished. We could only
dream of that kind of performance before.
Ten years ago (1998) at the local once a year float plane Fly-in two of our model airplane pilots
(the airplane owner also flies as the captain of a Boeing 747) had an traditional looking balsa
frame high wing airplane that then made up half of any RC flight line, to which he had added
floats. Back then most of us flew on cheap brushed can motors (I had 14 ounces of thrust for one
minute duration in my first electric airplane), he had an early brushless. In a 48 ounce airplane
he had 60 ounces of static thrust. At the field the power pilots were horrified, “better take it all
the way down to the end, give all it has and if it won’t lift off better shut it down before there”
they directed. So he taxied to the far end of the lake, started with quarter amps and slowly
increased it, then right in front of them when it looked like it might actually take off they all
cheered, so he gave it full amps and pulled straight up, for about a quarter of a mile. Nobody
would speak to them for the rest of the day.
For a decade I bought most of my stuff barely used from the power pilots who regretted that
electrics didn’t work, they have since caught on. I wound up waiting inland 2008 and went over
to a local “average” club to fly. I have fond memories of where their runway is now, when it
was a field as a teenager a friend and I used to fly free flight and control line there in the 70s.
The morning was a little breezy, about 10 miles an hour averaging 45 degrees to the runway
plus gusts, so I put my Mini Mag in the air. I was running an 2100 kV inrunner on 3S with an 8
inch folding prop at 30 amps. Using all 4 channels I walked it straight down the runway at head
height at a ground speed a person would walk, then hit the amps and went straight up for a
couple of hundred yards, after which I chased slope currents and thermals for half an hour. If
you ever get that good you can fly next to anybody without feeling inferior, when I landed 30
minutes later all questions about my flying skills were answered. What really surprised them
was that I do it with a simple non computer transmitter and no gyroscope stabilization, and the
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general used look of the airframe. But that Euro 25 cheap motor always did vibrate. When the
back of the case came off it not only wrecked the motor, it took out a $90 high voltage speed
control. I wasted more money on cheap stuff then I ever saved.
Right around the corner from my parents there is a green grassy park that would be an inviting
place to fly, except for the fences for the baseball fields, (32) forty foot high light masts, and
being right next to a prison. I had been flying there for months when one morning I arrived to
find that the whole place had been covered with, well, manure. “Shaving cream” I thought to
my self and headed off to see if I could fly at the old field. 11 stop signs, 5 traffic lights, five
miles and 22 minutes later I demonstrated my flying abilities. After getting aquatinted I asked if
anybody had ever thought about flying at the field across town. I was told “You’d have to be a
fool to fly there”.
Even the Easy Star is not perfect, in order of importance:
Although the wires linking the servos to the control surfaces function completely satisfactory,
because they are smaller then what was previously standard many servo arms have to be redrilled to reduce the free play. A little bit of slack around the wires is ok, just not more then
about half the diameter of the wire. The elevator is more critical then the ruder. The thinness of
the wire, it’s minimal mass and ability to “give” a little are the reason the servos don’t break on
impact.
Pilots, who in the days before ARF and foam were by necessity builders, have difficulty
believing that the thin wires work, me included. I now use them in my 4 foot wingspan 450 watt
foamie, with HS 81 MG servos. Unlike the glow plug set that shake and get soaked in oil,
electric airplanes are clean and nearly vibration free, the control parts don’t need to be as over
dimensioned to allow for constant deterioration. These new wires work so well that the Nyrods
we used for forty years are on the way out.
Only exactly enough parts are included with the kit. Pay attention that you do not lose the tiny
nuts when working with them. Try working over a towel. Even after making sure that you glued
the nuts in place, check them often. The tightening of the nuts and little black lock screws
demands finger sensitivity that if you don’t have, get help with. Have somebody that knows
what they are doing check the whole airplane before it first flies!
The antenna, right there where it bends out of the fuselage and into the belly tube, may easily be
sheared off. Even worse, the rest of the antenna is enough for short distances, only when the
airplane is further out is contact lost. Improve it with some tape. Even better, get rid of the long
FM antenna by using the 7 inch antenna of a GHz radio system which stays inside the fuselage.
As time goes by repeatedly replace the piece of tape on the bottom of the fuselage.
After many flights the copper in the dangling portion of the antenna gives out, if reception starts
to fall off (you notice the airplane not responding out where seeing which direction it’s flying
requires concentration) try replacing the receiver antenna. I wind the length of antenna that
would otherwise hang out around a piece of foam inside the airplane. In theory that shortens the
reception range, I can’t fly far enough out to confirm that, and nobody else flies that far out.
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If you slam the airplane into the ground enough first the old style receiver’s crystal and then the
any receiver will give out.
It is physically possible to install a Park Flier receiver with it’s limited range in an Easy Star,
but, even though manufacturer’s published range seams reasonable, one day the airplane ceases
to respond to the transmitter and just keeps on going, and going, and going... See above, in the
phase where you learn how fast things can go wrong.
I use fiberglass on the belly of my planes. Since it was not reasonable to clean out the dirt
between the foam grains of my first Easy Star, Twin Star and Mini Mag when I decided to start
improving the weak points, the landing stains are visible through the fiberglass. Call it contempt
or practicality, see above, nobody spends more time in the air for less outlay.
There is no reduction of the range of the radio by installing it inside the plastic tube. I have
demonstrated a mile range with the little Hiteck or simple Graupner FM radios, that is sufficient,
you cannot see the airplane that far away anyway. The radios from Spektrum have more range
then their specified thousand yards. I get fussed at by other club members when flying out past
600 yards. To make it clear, install the FM antenna in the tube under the airplane just as
Multiplex directs, if you still have reception problems the cause is elsewhere. Do not do the
range check with the Easy Star on the ground or on a piece of metal (such as your car) but
instead on a carton or with somebody holding it so that nothing blocks the radio reception.
Beginners have a tendency to point their antenna straight at the airplane as if there was an
invisible control line directly to it. In doing so they produce the worst possible reception, of
100% transmission capacity there remains only 3% at the receiver. The amount of signal at the
receiver is dependent on the orientation of the two antennas to each other. Beginners often point
the antenna at their airplane while landing, in doing so they have caused the poor radio
performance. That can be the whole reason why a radio that works fine at vast distances loses
contact at short range. The other reason for failure of radio contract at landing is just too many
other FM transmitters on the flight line close by. The correct position of the transmitter antenna
is vertical. The short antenna of the GHz systems seems to minimize pointing the whole
transmitter. The most common reason for apparent radio problems on landing is actually stalling
the airplane by trying to land at too at too slow air speed.
I could never convince most pilots in California to land at a higher speed then just enough to
barely stay flying, They insist on landing so slow that their precious airplanes were on the edge
of a stall and they would not fly in any wind. They would hold me for a fool, except that I fly
and land my low wing loading motor sail planes in the wind anyway, the trick is to fly it onto
the landing. The extra speed that keeps the control surfaces working (and the wing flying) will
quickly scrub off on the ground with no damage to the airplane. If an Easy Star stall/lands at 6
miles an hour and you are flying in a wind of 8 miles an hour you not only need at least 8 miles
an hour air speed, you need more like (6 plus 8) plus 4 or subjectively, the ground speed
coming in must be faster then with no wind.
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That’s why man carrying airplanes have brakes, so they can still be flying when they touch
down. Ever notice the squeal of the tires, the air brakes and the thrust reversers of an airliner?
My Piper stalls at 45 miles an hour air speed in level flight with just me and empty gas tanks, I
land at 55 to 60 mph. Part of the reason for using flaps is so that the engine may continue to be
used to adjust the rate of decent and keep airflow over the tail.
Go down to the beach and look at the breaking waves crashing in, that’s about what the air
moving over the ground looks like if you could see it. Because they were just barely penetrating
the through the air, in a statistical spread depending on where they hit the crashing wave,
sometimes the airplane would plunge down, sometimes they went through and sometimes they
pitched up to stall. The pilots always complained they lost control, of course they did. When
the wing quits flying you can wiggle the control surfaces all you want, they have to have air
moving over them to function, they had stalled their airplanes. When we went to GHz and
interference ceased to be a factor, and foam meant that the radios survived small crash landings,
it could finally be demonstrate to them that they had all the radio connection they needed, they
were causing the stalls themselves. But they still wouldn’t change they way they flew.
Traditions die hard.
Most Multiplex airplanes are self jigging. The tail of the Easy Star is not, even a slight vertical
mismatch of the fuselage halves (which may occur in the foam cores too) will rotate the tail
relative to the wing. Try putting the wings in and using them to align the horizontal stabilizer by
leaving the back third unglued until the front can hold the wings. Even if it comes out a little off
Easy Stars still fly just fine as long as the tail is aligned with forward air flow. The same for
aligning the motor, it should point straight with the fuselage.
My pervious Multiplex airplanes just went right together, and it never occurred to me that I
would need to be more deliberate assembling the Easy Star tail, or that I would be making so
many flights with it. It irritated everybody that the tail was rotated about eight degrees clockwise
and it still flew so well. With so many new members we don’t all know each other anymore.
One day somebody commented “that airplane looks like shaving cream, but it sure flies well”.
Two past club presidents didn’t even look up to reply “it must belong to out our Fool”.
Many have enlarged the ruder. For those who’s flying skills have progressed enough, or are
using heavy model car size batteries, or flying in the wind, the increased control is not only
more fun, without the increase in rudder area the airplane can’t be adequately steered. Just don’t
over do it, double the standard width at the original height is enough, additional weight that far
back makes for balance problems. I glued on a cut down ice cream container (the brand name
Moevenpick, flavor chocolate chip, was clearly visible) for my fourth Easy Star that I wound
up giving to a beginner. Start with 20 degrees left of center and 20 degrees right of center.
Don’t forget to clearance for the elevator at full up travel. The elevator is just fine the way it is.
A correctly balanced Easy Star has the elevator neutral i.e. in plane with the rest of the horizontal
stabilizer. Often to compensate for bends and damage the ruder may need to be trimmed a little
right or left.
Of the many changes I have seen to the airframes shape widening the rudder is about the only I
consider to be worth the cost and effort, at least from a flying standpoint. But sometimes it’s
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just fun changing a foamie to see what happens. Both I and the former fighter pilot who first
introduced me to the joys of a powerful Easy Star at Mission Bay when using 250 watts-out
consider increased ruder travel to be more satisfying then ailerons, we like the simplicity. The
friend whom I built the Easy Star for his son prefers to be able to position the wings with
ailerons as does the friend I recently went on a flying safari with in his new neighborhood. If
there is 150 watts or more thrust on board and you are using a 3S Lipo of average weight i.e.
2200 mAh just increase the rudder travel each side to 45 degrees and use the standard rudder.
There have been four former fighter pilots, five airline pilots, six world champion RC pilots, a
helicopter designer and the senior programmer of the Predator that have flown RC next to me,
none of them considers me to really be a fool. The new club members have noticed that the
experienced club members pay careful attention to my flying and airplanes.
Material fatigue starts to show up in the control surface hinges of Multiplex airplanes at around
50 flights, since it is easily fixed in minutes with clear packing tape that isn’t much of an issue.
Those of who learned how to use a covering iron back when there wasn’t any other choice, have
the edge here in that the same iron (set on low) works for packing tape too. I tore the elevator off
of a Twin Star II at flight 54, the repair tape lasted until the whole airplane was trashed by
receiver failure at flight 421. About the same time on the larger airplanes the control horns start
to tear out, again fixing them is simple, try cutting down a plastic container and gluing it over
the horn. All of my personal airplanes include at least some lightweight specific for airplane use
criss crossed fiberglass reinforced tape (not the hardware stuff with the fibers only in the long
direction) or fiberglass, I do the reinforcement of the control horn attachments before the
airplane ever takes it’s first flight. Although never yet an issue with the Easy Star, the
connection between the foam crystals in the area of the motor mount of the front motored
airplanes starts giving out at around two hundred flights, that is why the whole airplane seems to
buzz with vibration. By the time you get so many flights in with your airplanes that the basic
foam is worn out you don’t need this guide any more!
Not everybody flies that hard:
I fly my Easy Star, Mini Mag, Twin Star and Easy Glider airplanes through all possible
maneuvers, including by wind, land them on tree surrounded rough fields with tall grass,
molehills, rocks, horse patties, mud, snow, standing wheat, sugar beats, rocks and sage
brush, with more control throws, in any case not as the trainer for a pleasant cruise around the
airport, and all of it with more power then typical. Maybe somebody that flew more relaxed,
stayed out of the wind and landed on smooth flat surfaces would have different experiences.
Repairs:
If you fly the airplane long and hard enough the hinges will rip out. Bevel out the rest of the
hinge until you have two smooth straight Vs and use a layer of packing tape top and a layer of
packing tape bottom to repair them. Goop brand glue can reattach many torn parts.
One breezy afternoon at Mission Bay (maybe twelve miles an hour with no gusts) only our safety
officer with his top of the line everything perfectly tuned gyroscopically stabilized controls
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aerobatic airplane plus world class flying skills and I would take to the air. He knows that
competitions are often held in less then perfect weather, we both like flying in the wind. I have
a one sided agreement with any pilots flying expensive material, I do not want to risk their stuff
with my cheap durable buzz bombs. See below, I was hit from underneath. They get the
runway area, I stay all the way out of their field of vision flying off to the side of them while
keeping at least fifty yards of separation and land off field. It would be rude to risk their
airplanes in a collision with mine, for their few minutes of flight I want them to be able to
concentrate on flying, not worrying about my careening around the sky. This time even more so
since the whole left side of my Easy Stars horizontal stabilizator and elevator were torn off. As a
five other pilots arrived and refused to take to the air because of the wind, each of them in turn
felt compelled to notified me that “Hey you fool, part of your airplanes is missing”. “ No it’s
not, I have it here in my pocket” I replied and showed them the missing half. I may be a flying
fool, but I’m courteous. We didn’t used to have electric airplanes that expensive, I decided to
change my flying to accommodate them. The half of the tail went back on with just Goop glue.
It stayed fixed, with CA repairs there once a break starts it just keeps breaking again.
I had been flying next to some of those pilots for a decade. Back before we ever dreamed of
gyroscope stabilization, foam wings you could stand on or affordable electric motors so
powerful that we ran them at less them maximum output. Maybe the other pilots are awed at the
World Champion and his skills, he tried to convince the other pilots that it was all right to fly,
but even with raged me and my simplest of airplanes as an example, they still wouldn’t take the
risk. They didn’t believe either of us in 1998, or 2008. Traditions die hard.
Do the blunt tailing edges matter?
As far as I can tell, in the speed range of the slower Multiplex airplanes, no. I tried a
competitors airplane a lot like the Easy Star, because after subtracting for the value of the
included motor, controller and propellers the airframe was only $35. The foam was awful stuff,
almost as soft as styrofoam. Still, I added balsa to the trailing edge of the wing and horizontal
stabilizator, the undersides had to be fiberglassed to have any chance of surviving real world
usage anyway and it had the advantage of securing the added on trailing edges as glue along the
foam never could. The airplane had one speed, slow. It’s only an estimate, but apparently
other then the Blizzard and Ultra Jet none of the Multiplex airplanes fly fast enough for the
additional weight, time and expense of knife edging trailing edges to be worth it.
Interesting encounters:
That retired men, and sometimes young men especially in the early teenager age, find the
airplane interesting is obvious. They are why I wrote this down. Most women view me as a boy
with a toy, but not all of them, sometimes a woman finds it fascinating to watch too.
The two women with baby carriages, it wasn’t the babies that they wanted to see the airplane,
as former stewardesses they themselves were interested. What luck that my wife wasn’t there as
she considers every other woman in the world a competitor.
The grandmother that found it beautiful, and wanted to make an appointment for her grandson to
see.
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The half a dozen women who, through their sons, had learned how disappointing failure is and
wanted some direction.
The couple watching me spend 45 minutes on a single battery climbing into the wind to coast
back down, turn around a big tree a couple of times at just over walking speed and climb out to
800 yards away and 400 yards up and again. She had been a glider pilot as a young woman and
recognized that I was taking advantage of some slight slope lift. With my wife in attendance,
despite her having no video game or other RC experience, she made a credible go at flying the
plane! It’s rough unconventional appearance (a thick wing version of my Sturmovik with a well
matched motor and propeller delivering 110 watts output) was not an issue after watching it fly
and land.
The one exception, an irate bird watcher.
But the most surprising encounter:
A big black horse (gelded later then usual) who just had to know what it was that was in the air.
Where I live is ringed with horse stables, regardless of the laws that say I may fly there the horse
people have absolute priority. There is no comparison between the value of my toy and a rider
on a bucking horse, I would rather wreck my plane then risk them or anybody else. My warning
distance on horses is 220 yards, the airplane is either landed or flown away from them. 95% of
the riders are women and almost always good looking healthy ones at that. The terrain is hilly,
with flights lasting twenty minutes and longer and my vision concentrating on the sky I can’t
always see them coming up behind me. I often park near the horse stable where the gelding was
penned up outside, at the closest I was flying at least 330 yards from him. It was the fifth time
of him bucking up and down and furiously whinnying as I put the airplane back in the car before
I realized that he wasn’t interested in me, or the grass I had offered him previously as a greeting,
it was the airplane that he just had to check out. After I presented the Twin Star to him to sniff
all was quiet. But, six weeks later as soon as I changed to another airplane, even with the same
color scheme, he wanted to see it too. That’s when the worried lady owner found out that we
were already aquatinted.
At least 99% of the people you will be associating with flying radio controlled airplanes will be
men. If it’s women you are really interested in take up horse riding. See the warnings about my
other hobbies.
How much room do you need:
At the start with you need at least 200 yards in every direction. Later you can use less, or a lot
more.
If the only place you reasonably have to fly is small check out the ultralight indoor foam
airplanes. In Germany we fly in gymnasiums, the same airplanes get used in San Diego when
the air is still. Of the Easy Star, Easy Glider Electric, Mini Mag and Twin Star the Twin Star is
the biggest and the most agile. Make your first flights at a flying club. Beware, you are
welcome as a beginner, but you have to initiate contact. The men at the field are sociable (well,
electric pilots are) but not outgoing, you can stand there for hours if you don’t ask for help.
Learning to fly:
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Prepare yourself for surprises, first on the ground, then in the air. We can call out directions to
you while you are trying to fly, but nobody can mentally process the unfamiliar act of remote
control and follow spoken directions simultaneously. The modern simulators are a big help, but
nothing replaces actually flying. The deciding factor isn’t your ability to fly so much as how
long it takes you to learn to control something by remote control. Those who have been playing
video games are already almost ready to fly. But they often have a problem with now you are on
your feet and turning and how unpredictable the real world is. The airplane gets into a difficult
position and pow. Playing video games or even flight simulators cannot duplicate the statistical
likelihood of non repetitive conditions (chaotic for the mathematicians in the group) that exist in
the real world. If you do not play video games and do not have any other experience
remotely operating something which can turn completely around you have a long
experience ahead of you, like twenty to sixty hours to get the hang of it.
In a complete book learning to fly would be the longest entry, except that there are plenty of
books for beginners already. Aerodynamics for the foamies described here are no different
then for any other airplane. That whole airframe exists to create airflow and hold the parts in
alignment, the material with which that is realized is not the determining factor for flight. The
many well written books already in print and videos are just as valid about flying as they ever
were.
There are feature length magazine articles and books about every paragraph here. One reason for
setting down what to use is that as a beginner it is almost impossible to differentiate between
what is applicable to you and what is necessary for the fifteen thousand dollar exhibition
equipment. I’m didn’t write this to reinvent the wheel about flying, just to direct you about the
new materials and fill the void about equipment that most of the beginners books would rather
not admit exist. Since the discussion centers around the best trainers ever it restricts the
materials choices and makes listing specific costs possible.
Be warned:
Because the plane is so easy to fly, can stay so long in the air and be used all over, you may
have a tendency to forget everything else, like your family and your job. I don’t know how
many times I intended to just stop by the flying field, and stayed the day. Or how many times I
sneered at a beginner standing there with his airplane in silence “are you here to fly or just
watch” and coaxed him into getting flying. Or waited until somebody had a few minutes to
recover from trashing their airplane and hopes, until I handed them the transmitter to “It’s a dull
trainer and already beat up, since you are here why don’t you get some experience and fly
mine”. Or took somebody’s airplane half apart and put it back together right so it would fly.
Retirees that tried it as young men are fascinated and full of questions. But don’t forget, that
what is fun for you may be an annoyance and even a threat to others. Particularly horses and
their riders might be endangered. See above, you need insurance.
Other Airplanes:
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Even though the purchase price of the basic airframe of all four airplanes covered here is nearly
the same, if we assign a relative value of the cost of the fitted out airframe and required batteries
(the part of the whole system that flies) to the Easy Star of one, AND allow for the durability in
the hands of a beginner cost of repairs, the cost of a Mini Mag or Easy Glider Electric would be
about double that of an Easy Star’s and the Twin Star’s two and a half times as much. That did
not reflect the costs of the radio and charger. Those are average guesses, it depends on how
many times you crash and what you selected for equipment. I once watched an overconfident
beginner ruin two $55- Lipo batteries in three flights with an Easy Star. With it’s long nose and
ability to use more durable NiMh batteries the Easy Star might work out cheaper then the Mini
Mag or Easy Glider Electric. If you had my fleet to learn with, we could try all four to find the
one you feel most comfortable with, otherwise, my recommendation is: Start with an Easy Star.
The Easy Glider Electric:
Many people love to fly thermals. Because air is nearly transparent the sun heats up the ground,
as the air at ground level heats up it expands becoming less dense then the air above it.
Eventually a vortex of warm air punches up through the cooler air. With the right airplane you
can ride the rising current (correctly called thermals), for hours. Motor Sail Planes also make
good mild wind slope soarers, all the more so because you can fly into “dead air” and get back
up. At the expense that you have to land nose first on that motor and prop. The long drawn out
wings and thin fuselage of that type of airplane and the quiet graceful flight are appealing. For
some people the hunt for thermals is addictive, In the USA they are the pilots that stay with the
hobby the longest, they are also the ones that really need an elaborate radio. It is possible to fly
thermals without a motor, but, when towed aloft with a winch to 400 feet even the best
machines being flown by professionals are back on the ground in less then two minutes if they
don’t find lift. Pure gliders require balancing weight in the nose, as light as our motors and
batteries have become they are only a little heavier then the balance weight required. With a
motor sail plane you are independent of a winch, tug or slope wind, you can keep going back up
when ever you want.
Multiplex has a basic thermal airplane in the Easy Glider Electric that is an excellent choice for
beginners. If it’s the flying time in the air between landings that you need the Easy Glider
Electric stays up the longest, but you need help getting back on the ground. It flies fine on a
basic 4 channel radio, with this airplane a beginner needs both the ruder and ailerons. If
thermals is what interests you a more elaborate radio right from the start is worth it. An Easy
Glider Electric may be purchased set up for either a geared brushed motor and folding prop (now
obsolete and being dropped from the line up), or a couple of different brushless setups. The
Easy Glider Electric was the last airplane for which the brushed motor setup was still viable. It
comes down to what you can afford, and how much wind your area has. In Southern California
and Central Germany we have a few days with strong winds (when nobody but the slope animals
fly, we know who we are), some days with mild variable winds and a lot of calm. The Easy
Glider Electric does fine with the wind up to about eight miles an hour and great in the calm.
The more wind you have the more time the motor has to run and the more important the power
set up is.
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After you break the not very good folding propeller that comes with the brushed motor and it’s
gear box, put a better one on it. The brushed motor transmission will not sustain more power
then a Speed 480. Although it is easier to buy the brushless machine right at the start, the
brushed version is easily converted to a direct drive brushless outrunner.
I paid Euro 35 for an Easy Glider and converted it to electric. The servos alone were worth twice
what I paid for the whole slightly bent airplane.
Thermals are not satisfactorily modeled on a simulator, the computer just can’t activate the wind
on your face as it changes direction, the birds and other subtle signs. It is still worth it to
practice on a computer, the basic handling of the airplane coming to you while landing is the
hardest part. I never did get much out of just flying thermals, it’s not my thing. But, I often use
them to extend the duration of my flights with other aircraft.
As I write this in January the previous day I was out flying a Sturmovik with snow on the ground
and no perceivable wind. My landing area is the meter wide grassy strips between the plowed
fields and farm tracks, it could be described as lumpy grass with mud. What a great view while
wandering around flying, I land when I need to. One flight I shut off the motor a hundred yards
out and fifty up expecting to glide back, only to ride a thermal up until it the florescent orange
underside was almost out of sight a kilometer away and a kilometer up. Hunting thermals is
reminiscent of looking for a steady breeze up a hill, lobster, and willing women. There are
times where you know conditions should be right, and strike out. And sometimes they show up
unexpectedly. See above, that’s when the lady owner found out her horse and I were already
aquainted.
The original Sturmovik was WWII Soviet ground attack airplane little known in the USA. Of
the supposedly 34 thousand produced they had to be simple and cheap to manufacturer knowing
that they were going to be flown off of lousy runways and shot up. My Sturmoviks are based on
a once famous easy to build and fly sport trainer (Das Ugly Stick) designed by Phil Craft, the
man who brought affordable radio control to the masses. With it’s one meter wingspan it is easy
to transport and uses the standard length materials for spars. If you take a good look at it that is
about what the German Rat Racer series Gumpf is. The front end is streamlined to take
advantage of electric power in affordable sizes from 85 watt to 350 watts. With 300 watts it will
fly straight up. The wing and prop are both up high, it’s the belly and bash plate nose that hit
the ground. This is probably the only RC airplane that you will ever hear the term “bash plate”
applied to. That thick semi-symmetrical wing doesn’t do anything really well, but it does some
of everything. The whole thing is not only tough, it’s dimensionally stable and waterproof.
Constructed from depron (an insulation material) and fiberglass (ten times as much on the front
half as the back half) if you are a good enough pilot to not smash the motor on landing it is a
replacement for an Easy Star in a more economical size. My neighbor in Germany, the one who
flies a Multiplex Culinaris and a Boeing 747, had me build one for him.
The Twin Star:
The Twin Star doesn’t really do anything well, except, thanks to the long nose that prevents the
motors from hitting the ground on landing, it can land on almost anything. And that makes an
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unbelievably greater area available for flying. It is the only airplane that is competitive with the
Easy Star at putting down on an uneven surface. That is probably the reason we met each other.
For those that fly the motor in front, they can only fly there where there is a suitable landing
place, a Twin Star can stop on just fields. In comparison with the Easy Glider Electric, Mini
Mag or Mentor that may be the most important advantage of the Easy Star, but it is enormous!
The Twin Star can require the most initial cash outlay of the basic four airplanes discussed here.
It is the best of the four at flying in the wind. It will fly with the Speed 400s, but see above, I
tried...
An Easy Star is nominally a “full house” aerobatic airplane in that it has ruder, motor, elevator
and ailerons, but, I often fly with a 3 channel radio on just ailerons and elevator although it will
fly ok on just the rudder and elevator too. In comparison with the Easy Star how the Twin Star is
positioned in the air is easier to see, and it more resembles how an airplane handles on a
simulator, some beginners do better with the Twin Star. Plus it sounds neat. The newest
simulators for Radio Control costing a hundred dollars on up model an Easy Star just fine.
Many beginners find the visual representation easier with the Twin Star. With the free download
Program FMS, even though it is very simple, the Transal Twin most resembles the Easy Star.
With the MS flight simulator the Cessna 182 comes close. See above, practice on the computer
makes sense and unplanned outlays.
Particularly on days where there is wind I wander the countryside looking for hills where I can
partly slope soar and play with the wind around trees. Let’s examine that statement again, play
with the wind around trees. No wonder some of the other pilots consider me a fool. And yet my
Twin Star made it to 421 flights. Larger diameter propellers have a better efficiency, but the
longer ones can hang up in grass and tear the motors lose. Experienced based it’s ok on smooth
grass up to 8 inches, on long grass better stay with 7 inch propellers. The Graupner CAM series
6.6 X 3 Propeller puts out more thrust with less current draw then an APC 7 X 4 and are quieter
while doing it. They also cost more. This isn’t the place to save seven bucks on the price of a
pair of propellers. Although Multiplex offers decent quality motors and props, they are too
large a diameter for use except at a flying field, or (ugh) gold course. However, the inrunner
setup offered for the Easy Star and Mini Mag, times two plus a “Y” harness works well. But,
you should disconnect one of the BECs of the motor controllers and it is easier to use a single
larger battery. You absolutely must use two regulators with two brushless motors as otherwise
when amping up from stopped half the time one motor will either not turn, or run backwards.
Get help with the setup.
I never figured out why in internet discussions the constant wearing out of brushed motors was
never mentioned. Good luck using the internet for information on updating the motors of a Twin
Star. See above, lets just forget about brushed motors from now on. Although the upgrade
motors/controllers/props from Multiplex work fine on a runway, for my type of off field flying I
do not recommend them as they are too large.
This is the only one of the Multiplex airplanes where you should select your own components.
A Twin Star is a reasonable place to continue using model car size batteries if you already have
them, or can get them nearly free.
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Just hope you have enough altitude when it happens or better yet, don’t try it.
Launching with the motors already turning correctly and trying to always fly with some amps
doesn’t reliable work, you are gliding in for landing and hit the amps for just a little more and oh
shaving cream. The simulators don’t even try to represent what happens, it’s bad. When just
one motor powers up the wing on that side rears up and away. If one motor runs forward and the
other one in reverse it will flat spin even wilder then the vectored thrust indoor planes. I am an
expert at getting by inexpensively, take a guess how I learned the above. Refitting my Twin
Star with a third wire for each wing and wiring it into the factory electrical connection board was
an easy two hours. I used a piece of wire rod just stuck through the foam to pull the new
conductor wires in. It was another hour to sort out balance and position the motor controllers
where they get good airflow.
Let’s try the virtual dyno.
I like Scorpion Motors, they are assembled in San Diego California, I know two dealers
personally and they are nearly the same quality as the non competition Hackers that would be a
good, if expensive, choice. Neither is cheap, if you are out of the frequent crash stage better
motors are worth the money. We need to stay with the 28 mm diameter common to the Easy
Star, Mini Mag ect because that is what easily fits the Multiplexes motor mount(s). Scorpions
have the now standard 3.2 mm (1/8th inch) output shaft. For the Twin Star the Graupner 6.6 X 3
is my choice of propeller. As the Graupners are not easily available in the USA the APCs are a
good choice although as previously noted, the APCs are not as efficient as the Graupners, they
also slightly cheaper, noisier, and more durable. We have to chose a motor weight, lets try a
short length at 45 grams. To stay with the Castle Creations affordable motor controllers (or the
just as good ones from Multiplex) we need to stay below 17 amps, for comparison (and because
they are economically reasonable sizes) 2S 3200 mAh Lipos, 7 or 8 cell car packs or 3S 3200
Lipos were input. The amperage sets the controler size, you select the battery size, just make
sure that battery you fly with can handle the required total amperage, and, the voltage drop from
double the amperage may not be modeled for a twin on the internet virtual dyno, so the
performance won’t be quite as good as for a single motor. More voltage from a higher cell count
almost always results in better efficiency, if for no other reason then that the 0.6 Volt loss
through the wide open controler is constant, it’s relative loss drops as the absolute voltage
increases.
Using the standard 6 Volt Speed 400s with the black Multiplex propellers, a single 30 amp
motor controller and model car size 2500 mAh 7 or 8 cell NiMh batteries results in an Twin Star
that will just stay up on the motors for about 6 minutes of thrust and 8 minutes of flight.
When you start wondering where the performance went somewhere past flight 40 it’s because
the motor armatures are wearing out. That’s if the $6- motors last that long, sometimes they
throw a brush on 8 cells and continue to run for a short while. Or, it could be that because the
battery was not internally constructed for the required current draw and it is about done. If you
borrowed the battery from a model car enthusiast accustomed to using a cheap charger and not
expecting much exhausted batteries are a common problem. Do not ever use Tamia connectors
in an airplane, not even for one flight. A warning that a battery is about to quit is when it
refuses to take a charge. That’s why you need a charger that will give information about the
amount of power taken on by a battery. If you use the press on Multiplex or Guenther props they
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must be glued on. Otherwise you get to experience, with no warning, what it’s like trying to fly
a twin with one motor. And the tedium of finding parts/airplanes lost in the...
But lets be reasonable here, this is a great beginners airplane. If it weren’t for the Easy Star this
would be the greatest trainer ever made available. If you had to pick an airplane to start with the
brushed motors do work, enough to establish if you are interested in continuing or not. And,
important to a lot of people, it looks like a “real” airplane. It may readily be built with left over
parts i.e. used radio, car batteries, charger ect. Up grading an Easy Star is well worth it if you
are going to fly without a runway.
Scorpion 2205 45 grams 2S 3200 mAh Lipo 8 X 4 Prop(s) 16 amps each motor 59%
efficiency 43 ounces total thrust for 6 minutes. Average flights run twenty minutes. If you
insist on staying with 2S Lipos (with which you can mix in 7 cell car batteries without changing
anything), this works well.
The model auto set now has 2S Lipos configured for their cars, that big flat battery is a good
choice in a Twin Star, but, the cheap folded metal connectors supplied will not sustain the amps
required for flight. Do not ever use Tamia connectors in an airplane. Tamias over-heat and
disconnect themselves resulting in loss of all control, and yet when found in the wreckage the
radio works again, you must change to flight reliable connectors. Because there are more model
auto people then model flight people the price of some of their equipment is less then for
airplanes. The most common reason for ruining an airplane is taking off with the controls
reversed, the second most common mistake is using the wrong connectors.
Scorpion 2205 45 grams 8 cell NiMh 3500 mAh 7 X 4 Prop(s) 16 amps each motor/regulator
66% efficiency 49 ounces of thrust for 6 minutes. Although this is a heavier combination
because of the NiMh car batteries, it will still provide good flying. This combo will also work
with 7 cell NiMh packs for less thrust and a longer motor run time. 8 NiMh cells put out more
power then 7 cells, the flights are longer and more fun with 8 cells. The Twin Star isn’t that
sensitive to weight, or balance.
Just to aggravate a foam/electric non-believer, I once stayed up 53 minutes non stop with no
slope or thermals using this setup, and licked the wing afterwards. Then I put a 3S Lipo in and
showed him just how aerobatic it was. To prove how durable it was I landed in the 3 foot long
grass next to the runway. Later, in exchange for a case of wine (he’s a vintner) I assembled a
Twin Star including additional wiring for brushless motors and fiberglass for him. He had
somebody else paint it though.
Scorpion 2205 45 grams 3S 3200 mAh Lipo 6.6 X 3 Prop(s) 15 amps each motor/regulator
72% efficiency 46 ounces total thrust for 6 minutes. You do more aerobatics with more power.
Of the three brushless combinations this one has a THIRD more thrust and typical flights are
third longer then with the two other setups. Even if the dyno numbers don’t show it.
My Twin Star flies fine on 3S 2500 mAh LiPo batteries. This one can be a shock to people that
have not seen an electric/foam land it anywhere airplane before. A flying demonstration can be
done in circle 50 yards across, or a mile wide. My favorite combination in the Twin Star was a
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pair of the big flat car 2S LiPos in series (4S) running Scorpion 60 gram motors. By sticking
with a pair of used controllers at 12/15 (continuous/short burst) amps each and running two
BECs to separate the servos into pairs the price was acceptable.
What isn’t noted here is the flying speed of the propellers verses the flying speed of the airframe
at the resulting weight. The motor run time is not necessarily the same as flight time, with
heavier weights the airplane flies slower and the motors have to work harder, but dives and wind
are more fun, with wind you need more a higher wing loading i.e. more weight. With 6 minutes
of motor run time you have flights between 6 minutes and twenty minutes, more if you can find
at least partial slope lift, or thermals, or fly at part amps. There are more elaborate computer
programs for predicting overall performance, you aren’t ready for them yet, and don’t need
them with the Multiplex airplanes presented here. Nobody flies dynos, you have to try it.
Even so if you calculate in the missing repairs and long life as compared to any other airplane
built from „normal materials“ its incredibly inexpensive. I have made over a hundred flights
with no maintenance of any kind, the cost to drive to my, on the average, five mile away fields
that I fly at is more then the cost of flying the airplane. I want to fly and not build! I can wander
through the countryside with a Twin Star to fly at interesting places without having to concern
myself about a decent place to land, wind, snow or mud. That people, is the promise of
electric and foam we long waited for. However, airplanes that are subject to so many hours of
flight eventually succumb to the tiny electrical lines, unnoticed, one after another breaking until
one day, usually in the air, there is no more connection. See above, you should have insurance.
As for my Twin Star, it’s in the attic missing the motors/props/motor controllers. The details of
how that happened aren’t all that clear. All I can remember for sure is on that warm June
afternoon I needed gas money and my wife was going to work an all night shift. I must have
rolled off my inflatable mattress as I woke up the next morning on the ground wet and covered
with grass at the flying field. That airframe has had at least 8 different power combinations (not
counting various batteries), I can get more. Do not fly with a hangover.
The Twin Star I
There was a previous version of the Twin Star in a gray foam.
The Mentor:
I like the Mentor, but it exceeds the cost requirements I have for learning to fly. Watch yourself
in the store, you really need to plan the whole thing out before going in there. See above, and
then a few hundred more. It’s not the airframes that run up the cost. The Easy Star, Easy Glider
Electric, Mini Mag and Twin Star are not necessarily bound to a runway, the Mentor is. You
really need to be able to use all four channels with a Mentor to take off and land. However, it is
the re-creation in foam with electric propulsion of what was once the standard airplane for RC
flight, bigger flies better and it looks like a “real” airplane. If you want to spend the money it is
worth it, the Mentor can be a first rate trainer. There was a previous version of the Mentor, the
Magistrate.
The Merlin:
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Another great plane, but too small for it’s speed for beginners. It’s small size makes it very
convenient to transport, but even if you have somebody else build it a beginner needs to be able
to see the fine adjustments that make the difference between bliss and frustration.
The Mini Mag:
The Mini Mag is discussed in the following comparison section. Although a great flier, I
consider the Mini Mag to be too small for a first airplane.
Do I really want to spend the money for brushless and Lipo batteries:
Late afternoons on Mission Bay there is sometimes a little updraft slope wind on the beach. It’s
about 180 yards away and only goes up about 40 feet. I can fly a Mini Mag from that distance,
mine’s gaudy colors aren’t as ugly then. Thanks to the slope updraft, and landing six times to
swap out seven different NiMh batteries (8 cells in 800 mAh to 1200 mAh) with the 6 Volt
Speed 400 using the white propeller, I flew for an hour while a former fighter pilot club member
with his Easy Star (inexpensive 3000 Rpm/V brushless, 6 X 3 APC propeller and a 3 Cell 2200
LiPo brand cheap, 35 amp basic speed control) without the updraft stayed up the whole time
without ever landing or changing a battery. That Easy Star combination has been demonstrated
to stay up (67) minutes on one medium sized battery. That’s right, over an hour. In that single
event I used up one eighth of the expected life of a Speed 400, he used no mentionable life of his
motor. From his battery, rated at 2200 mAh, he used 1600 mAh, I used from 400 to 600 mAh
per battery. See above, what brushless motors with LiPos can do is almost unbelievable.
Watch it, all that electrical capacity of LiPos doesnt come without risks:
When they first became generally available Lipos lasted about fifty flights, but not a single
really bad crash, we now expect at least a hundred to two hundred flights out of them, and they
still can turn into flammable junk after hitting the ground hard once. Despite the improvements,
Lipos can burn. Contrary to the article in the leading German Model Airplane magazine a few
years back, all it takes is inputting one cell to many to the charger, or specifying too high a
charging rate to turn them into a swelled sausage of hot hydrogen gas with a built in spark. The
easiest way to burn Lipos is to have various size/voltages and forget to reset the charger when
you change from one battery to the next. Even the newer chargers that can automatically select
the cell count fail to get the voltage right sometimes. The same thing happens if the case is
damaged by an impact.
Two members of the club had fires right at home. One lost his garage. The other flung the
smoldering thing off the kitchen table out into the yard, where it set the dried grass of his lawn
on fire. Do not charge Lipos unattended, put them in a flame proof container to charge them. I
have yet to have a problem with any Lipo batteries.
Not everybody learns the same way:
Among others were two members of our military. They had both recently been in Iraq, both of
them were technicians. It was clear that part of the reason they were here with us was to escape
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the war. That, and the constant pressure from others was more then their personal life could
stand. One of them let himself be advised and quickly caught on. More then once as his
batteries were charging he flew an Twin Star of mine.
The other one absolutely wanted to go it alone. See above, most radio control pilots don’t want
to crowd. Twice, because of small things, he flew his $400 expensive Magistrate into garbage.
Only the transmitter could be reused. Afterwards he decided to use other methods to learn, he
began with a series of lighter less expensive airplanes. I often fly at dawn, because I’m already
awake, and in any case there is no wind. Which is for a beginner with a light airplane a great
advantage. As the only one in all the years he took the recommendation to try it at first light.
One morning after we had seen each other a dozen times it was just the two of us. All his park
flier Piper could do was climb in a circle. It just flew in a tight left curve until he backed off the
amperage, at which it crashed. I was tired of watching. I demanded that he let me inspect his
airplane. But, at the same time I put an Easy Star up a hundred yards trimmed for a slight climb.
“Please try it with something we know flies well. I know you can, but your airplanes are always
out of order.” For emphasis I put the transmitter in his hand.
I just left him to it, no direction about how to fly at all. He was in the air for a total of an hour
including two well made landings to change batteries. My Easy Star and old NiMh batteries
were already worn, that bemused look on his face as he realized he had a grip on flying was
worth risking them. A simple mistake prevented his Pipers rudder from moving correctly and
the battery was in the wrong place for the balance. All that was needed for successful flight was
present, we only needed to correctly center the servo arm and secure the battery at the right
location.
Occupationally I have to manipulate the people around me, among friends and at the flying field
I don’t like doing that. The same as the soldiers, the relief at not having to behave for a
commercial purpose is a reason for being a member of a club. The soldier was really
determined, but the rest of them had given up on him. What he needed was a calm person that
didn’t come through like an officer. And the self acceptance that he wasn’t going to get it alone.
See above, others have different experience, there is more at play then the choice of materials.
Those two difficult cases were the exception. Dozens of time people let them selves be easily
guided. How often I have had to take an airplane apart and adjust everything. How often was the
airplane of a beginner not fit to fly and we practiced with one of my simple airplanes until they
recovered their self confidence. Included were two airline pilots. Once, on his first flight after
all of five minutes at an altitude of a whole 35 feet an experienced radio controlled car driver put
his plane in inverted flight. It seemed so easy to him. Shortly afterwards his Easy Star (from the
complete kit) broke into three pieces on impact. So we flew my Easy Star instead. I just can’t
stand it when somebody full of enthusiasm is at the airfield and doesn’t get to fly.
Once in a hobby shop I came into discussion with a former F-18 Pilot. One of the fastest planes
in the world. Please don’t take it as aristocratic that on account of my father having been a
Bush Pilot in Alaska that I learned to fly very early. I have never piloted more then 360 horse
power. Our 140 horse power Piper is just a financial burden. Back then a small airplane cost no
more then a middle class car. Nowadays the upkeep alone is $4000 a year. I used to set up and
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program expensive metal working machines in real 3D, I am also a structural design engineer
and help build light general aviation experimental aircraft. We were in agreement that it had not
been worth it learning to fly without help. We both needed about twenty hours in the air and
uncountable crash landings before were able to take off alone, circle once and land, without
breaking something. The little bald headed clerk behind the counter looked like just any retiree,
but he had flown the F4 Phantom Recon jet fighter in Vietnam. He was cool enough to have
gone into afterburner to out fly an anti aircraft rocket. As those pilots themselves put it “Alone,
unarmed and scared shaving cream less”. It took him forty hours to learn to fly radio control. If
we needed that much help, what makes you so special?
In Conclusion:
This pamphlet, even if it seems complete, is barely enough to give you a glimpse of the material
and social requirements for learning to fly. There is almost nothing about flying or adjustments
included, see above, there are plenty of books for beginners already. Unfortunately, what you
need the most, no text can convey. No book, which this is intended to complete, and also not
the instructions from the manufacturer(s), can replace the help of somebody that already knows
how to fly. Even if their directions conflict with mine. Do what ever you have to do to get help,
even if it means a long drive to find other RC enthusiast when getting started. See above, the
women who through their sons found out how disappointing failure is.
Please, don’t try to learn to fly alone.
The shame of the club:
Unfortunately my predilection for rear driven airplanes built out of packing crate materials,
together with a tendency to stay in the air for hours, did not make me popular with everybody in
my club. Once at the airfield, after flying for 3 straight hours (2 chargers and 12 batteries)
including the irritating whine, all 20 pilots present demanded that I “take a break”. Another
time when I was hit from underneath by another pilot so hard the battery bounced out they all
gave a cheer. The attacking pilot was given approval to paint a Zagi flying wing on his motor
cover. At a monthly meeting they threatened to ban me from the flying field if I continued to fly
rear engine airplanes. That I continued as a member was due to having helped 10 of the 24
members who voted learn how to fly and that two past presidents of our club, one of whom now
manufactures racing electric motors, having developed a taste for the fresh lobster I trade them
for repairs to my motors and controls.
I had to agree to cease teaching others how to build and fly flying wings and am restricted to a
life time limit of 25 of them. I was also directed that further discussions like the one with our
staunchly heterosexual club president about the cost of coming and going in Tijuana, be
conducted in a bar instead of at the flying field. Although since intoxication is, like the opposite
gender, not on the approved discussion list, they would have recommended a restaurant, except
for that time we went out for Tai food and I ate more then my fair share. For my benefit the
dress code was clarified in that even you are wearing a tie, a shirt is required to fly at the field. I
was reminded that the insurance is not valid with me laying flat on my back to fly (I was once
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kicked by an older member to see if I was still awake as he could not see the airplane, others
have tripped over me) and by the time nobody else can distinguish my airplane from a dot in the
sky I have way exceeded the limits. I was told to quit wandering around talking with the
transmitter in my hand and the airplane in the air, again, insurance stipulations that the pilot
stay in one place and concentrate while flying.
The German have a saying, nobody is completely useless, they can always serve as a bad
example. It was decided to warn beginning pilots about me, namely that just because that fool is
happily flying that way does not mean that you should, or can. That time when 4 beginners with
stock Easy Stars all landed off field to damage their airplanes in wind speed that was faster then
they could fly was particularly discouraging. They were behind me where I didn’t notice them
and they hadn’t thought to ask if I had six times the power, a much more effective rudder and a
lot better flying skills including being able to land with the motor on right next to me where I
could grab the airplane before the wind could flip it back up and send it cart-wheeling. In
comparison with the respect demanded by the 7 horse power 180 mile an hour F5B airplanes just
revving up (it brings visions of their airplane turning into confetti) and the ohs and ahs of the
obviously only the best preparation and flying is good enough inspired by the $3000 F3A
competition aerobatics airplanes, the dilapidated appearance of my stuff, my apparently
complete disregard for wind and constantly flying too far, too near, too high and too low had
been demonstrated to provoke behavior among other pilots that would, in the absence of an
example, be reckless.
And so, without admitting guilt, I agreed to start behaving in a more acceptable manner. They
were all pleased that I took to flying airplanes with the motor in front. See above, Twin Star,
Mini Mag and Easy Glider Electric. And then the Easy Star came on the market.
Therefore; This pamphlet shall not be distributed in San Diego California, otherwise you may
pass it along.
2009 Updates: This sections text does not exactly match the german language one.
I am a master scrounger and often use behind the times equipment to get by, but the old
equipment is just no longer practical. Do not buy a FM megahertz crystal tuned radio new, get a
channel-less one in the GHz range. It’s time to just throw out everything that went with brushed
motors and Nickel based batteries, those in the transmitter excepted. NiMh batteries are no
longer the standard, Lipo and other chemistry are now what is being used. If you have regular
help you should go directly to the newer batteries, even though the NiMhs hold out crashes
much better. The battery shelves have been cleared for Lipos so much so that it is now difficult
to find NiMh batteries to buy. And too, the ratio of price to performance and weight has now
changed in favor of Lipos.
A chance meeting, an economic comparison: There is no paired german text.
Current to summer 2009 Frankfurt am Main Germany. Costs are in Euros, although the current
exchange rate is about 1.4 USD gets you a Euro, multiply the costs in Euro by about 1.25 for US
dollars as hobby stuff is generally a little cheaper in the USA.
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At the 12 mile away (travel cost round trip Euro 8 or USD 12) flying field there was a beginner
with a complete radio controlled airplane setup. It was a semi-scale model of a Citabria (a
common US built two place high wing private airplane that is at least partially to completely
aerobatic at the cost of being a little heavier and more expensive) with the tail surfaces increased
in size about 20% over scale so they actually work. Wingspan was about 90 cm (three feet), it
was in nice yellow and black colors plus a decal for black/white stripes under the wings. The
package was complete included the airplane, complete ready to fly, a simple radio, a charger
and one LiPo battery. Total cost Euro 140. Still required were (8) AA batteries for the
transmitter. It looked great.
This beginner was lucky, he didn’t mind having the help of the other pilots, there is every level
of experience at that field and on that day there was no wind. We had to re-center the single 8
gram size wing aileron servo and clearance the rudder linkage. It was equipped with a 2S LiPo
battery of about 700 mAh capacity and a Speed 400 motor on direct drive with a custom scale
look propeller. A brushed motor needs a few full throttle flights to break in the brushes. With
that size and voltage battery the motor would put out just enough power to take off from the
landing here on a paved runway and last at least a hundred flights. The first flight lasted about
two and a half minutes. For the short flight it looked good and flew well.
The wing already had a dent demonstrating that the foam is little better then styropor. It needs a
layer of fiberglass reinforced tape under the wing and will not tolerate any bad landings. Here at
this golf course smooth area surrounding a perfect asphalt runway it has as good a chance as it
can get. It will last until either the wing, fuselage or tail snap in half at the first caught by the
wind landing. It will get dents from just being transported. If it lasts, the foam as a hinge
material will have to be supplemented with tape. The wing struts are just for looks, they in no
way brace the wing and it flies better without them.
There is no instant way to install a larger battery, the belly hatch and molded in tray are that
exact size. A bigger battery could be installed by removing the wing, which with the minimum
length servo cable is a nuisance. An extension could be easily added for Euro 3.
There is no way to increase the power of the stock setup although a Multiplex or Guenther (Euro
5 or 2 respectively) propeller would get a useful few percent more thrust.
Often in these simple setups the LiPo, along with everything else, is usually on the cheap side
and as such not internally constructed for the high discharge rate required for airplanes, it might
last 35 flights. It could be used for the receiver battery of a glider or power plane.
I didn’t see the charger, but it can probably charge both 2S and 3S LiPos through the balancer
cable. Other then the slow rate of charge, probably about one amp, they usually work fine, at
least for a while. But they give no information about the charge, such as the amount of energy
taken on or voltage, other then when the charge is complete. It takes an hour to charge even the
small capacity provided battery, proportionally longer with a bigger one. It cannot charge the
transmitter were it to be equipped with rechargeable batteries.
The radio was a simple 4 channel one in the, for Germany legal for airplanes only, 35
megahertz (the US standard for the, don’t buy one anymore except used, radios is 72
Megahertz), good. The antenna trails out of the airplane. It worked ok and I for one like the
smaller size of the transmitter. There are no provisions for changing anything on it, Germans
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don’t feel right about their radio until it is festooned with switches. Both servos are on the
minimum, they look to be the 8 gram size. They did not have steady or accurate positioning,
but that probably made no difference. They could be reused in another airplane.
If more power and duration are wanted it will require changing out the motor, prop, speed
controler and battery. The first step up is a 9 Amp brushless (Euro 25) that would swing an 8
inch propeller (Euro 12 with the required hub) requiring a brushless Electronic Speed Control
(Euro 20) and could use the original 2S LiPo although it would need some trim weight. The
restriction here being the weak motor mount, it and the cowl will crush on the first nose landing,
take note that that is never mentioned in magazine reviews! A better choice would be a bigger
battery at Euro 20 each.
He won’t be happy with the short duration and low performance of the Speed 400 for long.
Bringing the airplane up to ok performance looks to cost about an additional Euro 120 at which
he has two batteries in the 2S 1400 mAh size. It’s unlikely the non scale prop will be an issue.
The pilot did have a stock Easy Star, with it’s 2S LiPo, 6 volt Speed 400 and 40 watts at the
prop, so he did get to fly a while. Although the plane I had with me is not really a trainer, just
for the fun of it and so he could try flying with elevator and aelerons (like in his Citabria) he
flew my Sturmovik with a 110 watt folding prop and lavishly fiberglassed nose. He was all
smiles, didn’t crash and stayed up for half an hour on one battery load. Any concerns about
using ailerons and elevator to fly, or how my plane looked, disappeared. With it’s flat wing it
has no stability about the roll axis, for younger beginners that is an advantage as without their
realizing it video games have conditioned them to having to make constant inputs. With a stabile
airplane like the Easy Star plots that began remote control with video games get too
adventuresome too quickly as they are expecting to have to constantly force the airplane to fly,
and they are too confident about what happens in the air that they can’t see doesn’t exist,
particularly at ground level. Ultra light pilots get killed the same way. Older pilots find it a
relief to be able to let go of the controls and have the Easy Star fly itself a little. I wonder if he
would have felt different about his Easy Star if he had flown mine with 240 watts (motor Euro
60, Motor Controller Euro 40, Prop and Holder Euro 13, Battery Euro 45) at the output shaft.
Or, he could have bought a Mini Mag that has an expected life of hundreds of flights. It can be
cartwheeled, flipped over on it’s back on landing, slammed in on it’s nose so hard the propeller
breaks, skidded across a rock strewn sandpaper like empty lot and plucked out of a tree with
almost no damage. If you are having such a good time flying that you nail a fence on landing
(because it was too dark to see anymore) and tear off half the horizontal stabilizer, it can be
fixed by just gluing it back on. You can stand on the wing and, if you miss the servos, not even
know it happened. Nothing theoretical, I have done all of the above, and more then just once,
all with a single airframe. The motor can be changed in minutes (the upper limit for the airframe
is about 150 watts output), nearly any battery of a reasonable size fits in with nothing more then
gluing Velcro on to it. I didn’t have a price on the whole ready to fly kit, but it was probably
about Euro 120 more then the Brand X Chinese setup for seemingly the same thing.
With two servos (Hitec HS 55) already installed the airframe kit runs Euro 240, but that’s rudder
and elevator. The wing accepts aileron servos in less then an hours work for Euro 55. If you are
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limited to a three channel radio disconnect the rudder, or better, leave it out and use just
ailerons.
A better choice for the Mini Mag is to toss the 6 Volt Speed 400 and prop that are
included (it will fly with the in the kit brushed motor and prop, landing gear and all, on 2S
Lipos, but only barely), go directly to a outrunner in the 15 to 20 Ampere size (get an UdV of
1400 to 2200) and use a 3S LiPo (s) The motor control needs to be one size larger (18 Amp) or
about Euro 35. The 3S LiPos in the 2200 mAh size cost about Euro 35 to 55 each, get two if
you can.
For a radio the modern Spektrum Ds5 in the Giga Hertz range (with which you can
forget frequency control and interference) that requires no fussing or risks with who’s on which
channel, costs Euro 100. The servos, the four batteries for the transmitter itself (get Sanyo
Enelopes at any big electronics market for about Euro 3 each) and a cable to attach to a charger
are not included at that price.
A modern charger with balancer function runs Euro 100. It does a much faster charge
and gives some information about the amount of charge and battery that quickly comes in handy,
it also works at the flying field off the car battery and can (with a suitable cable) charge the
transmitter battery.
A lot more outlay, but this setup has three times the thrust and five times the in the air
duration! He won’t outgrow the radio for a while (for Euro 200 a Ds6i is a good alternative after
they get through the mid 2009 recall action) and the receiver (Euro 45 if bought separately) can
easily be moved from one plane to the next without having to route that long antenna of the
archaic FM radio somewhere. Instead of four minutes per flight with the Speed 400 setup, or
about ten to fifteen minutes of just floating around with the 9 Ampere brushless setup (which
would also work well in the Mini Mag) in the Citrabia, he has up to half an hour with the Mini
Mag. Instead of the charger taking three hours at home on 220 volt AC to load a 2200 mAh
battery, it’s an hour at the flying field on the cars 12 volt battery (less with the modern multiple
C LiPos), and it can, with a suitable cable, charge the transmitter. But, it’s more money up
front. Adding aelerons in the form of two more servos and the “Y” extension cable adds Euro
45, deduct the price of the rudder servo if you have the confidence to omit the rudder while
building. Even though I have four channels available I often fly my Mini Mag on the ailerons
without the rudder, the rudder just doesn’t get used much if the airplane has ailerons. For
example, in still air hammer head stall turns at the end of the vertical climb need the rudder to
make a nice sharp turn from vertical up to vertical down, if there is wind that can visually be
created with just the ailerons, the rudder is then just extra weight. I like playing with and
against the wind, with these durable airplanes that can be done without the nervousness of
expecting to have spend hours afterwards repairing the damage that would otherwise be
inevitable with traditional balsa frames. Since the Mini Mag quits moving in about fifteen feet
after contacting the ground (with or without landing gear) when landing, steering it with the
ruder is not needed if you can just convince yourself to let it fly all the way down the ground.
Motors can be swapped in less then an hour.
But, the Mini Mag only looks vaguely look like something at a “real “ airport. Kind of like a
Cessna 170. See above, when you find yourself soaring above while the other pilots are busy
making repairs how it looks will be unimportant. A Mini Mag can last long enough to get bored
with it. Similar to the Easy Star, the Mini Mag has an under cambered wing with trainer
characteristics, it is not really aerobatic, even I can’t get it to do much. Easy Stars and Twin
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Stars fly well inverted. It’s an effort to get a Mini Mag to fly upside down, it takes a lot of
elevator and power plus constant control inputs, control of all four axes is needed. That does
have advantages at long range exploring the wind, if you have the altitude just center the control
sticks and it will recover on it’s own, if you lose sight of it, it will keep flying until you spot it.
On safari we often fly so far away we can’t tell where the airplane is relative to the ground, we
just turn it away from the hill back to us. And sometimes we climb hills, fences, trees and on
roofs we otherwise never would have visited if the little airplane wasn’t so reliable and durable.
The small size of the Mini Mag relative to it’s flight speed restricts it’s usefulness as a trainer,
many beginner pilots can’t see it well enough or, put differently, it has already changed too
much of it’s position before they recognize what has happened. The larger Easy Star, Easy
Glider Electric and Twin Star are more easily seen. If what you really want is a durable land it
anywhere airplane that can do aerobatics, a Twin Star, with it’s twice as expensive double
motor setup and semi-symmetrical airfoil is a better choice. For reference, a Mini Mag flies on
one motor about like a Twin Star with two of the same motors and twice as big a battery.
The Easy Star, Mini Mag, Easy Glider Electric and Twin Star all make great trainers, better
then anything we ever had before.
My Mini Mag has 328 flights on it, previously used aileron servos included. I write a flight log
right on the wing, See above, the generally dilapidated appearance of my stuff, even the paint
and older log entries are fading. It was a great plane for exploring the new neighborhood with a
friend recently. Not great in the sense of the ohs and ahs of what you see at the flying club, but
great because we could use it! So what if it the Mini Mag does nothing really well, except it can
do some of everything. It was already beat up, so we didn’t mind the risk of landing where ever.
Even if we only had 65 watts on 3S Lipos at the 11 X 8 folding prop, it stayed up for twenty five
minutes a flight. The limited power made for challenging flying as every nuance of air makes
itself apparent at minimal flight speeds. Just for variety I had the rudder (with it’s beginner
travel) hooked up instead of the ailerons. Who demands that the motor has to be completely shut
off to thermal, if you find an up draft leave a couple of clicks of amps on and enjoy going on up.
Electric flight encourages a new flight profile that combustion and glider pilots could never do,
motor on to climb and motor off to glide. My motors usually only run 20 to a maximum of 30%
of the time. This wasn’t a beginner, so when the airplane flew out of an unlikely thermal a
hundred yards up in the late afternoon (just because air is transparent and you don’t feel the same
wind at ground level as the airplane up there doesn’t mean there aren’t things going on) and fell
out of the sky, because it stalled in straight level flight for no apparent reason, he very correctly
dealt with the unexpected. He attributed his automatic reaction to his many entertaining hours on
simulators, battle damage from air-combat included. And, just because they weren’t connected
to the receiver, when I inadvertently launched it with one aileron at full down, it still stayed
controllable with just the rudder and elevator. As his father, a former military air tanker crew
chief noted, that happens to the big ones too. I usually fly for at least 45 minutes. On some of
my three hour events I may wander, airplane in the air, transmitter in hand, extra batteries in
pocket for miles. For me the smaller easier to carry size of the simple 3 channel transmitter
outweighs the slight advantage of a bigger 4 channel transmitter. What fun! The memory of the
pleasant afternoons together playing on the wind looking for thermals and updrafts to extent the
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flight will outlast the inconvenience of being almost, but not quite, completely broke. Our only
cash outlay was for the gas for the five miles there and five miles back.
I love the ocean, but at three dollars a gallon for gasoline and 34 miles each way, even pouring
40 ouncers in a cup to drink at the beach would have cost more then going flying.
I will probably remove the wing and rudder servos from my Mini Mag and install them in a new
airframe. The glued in servo extensions and vital elevator servo (there is no benefit in waiting
until it finally quits and takes everything else with it when it does) will be discarded. Or I might
equip it with a new wing by spending the $28 for a replacement plus $8 times two for new servo
extensions and $6 for a “Y” cable and let somebody else have it. Currently the wing tips
(dropped down, just like my full size Piper with the extensions) are worn off, the leading edge
of the wing and horizontal stabilizer are nicked their full width and the foam around the motor
mount, even after reinforcing it with fiberglass, is so fatigued that vibration is a problem. I fly
my Mini Mag in the USA where a complete new airframe kit is USD 82. A new one would be
selectively reinforced with very thin layer(s) of fiberglass at wear areas: Belly to wrap around
the entire front end, leading edge and tips of the wing, the tail at the horizontal stabilizer out
two inches plus it’s leading edge, the interior tray for it’s full length to stiffen up the fuselage
(they bend right at the rear end of the cowl on the inevitable hard landings). Total time for the
fiberglass about a day. The rest of the plane goes together in about four hours. And they wonder
why my airplanes last longer. It would probably be equipped with a glued into place 30 mm
diameter inrunner motor with an output of about 150 Watts (it can get by with an 18 amp motor
controller, the motor will be down-rated with a smaller then maximum propeller) on a 8 inch
folding prop, even though that precludes an easy changing of motors. To get the prop to fold the
nose will be narrowed. My current Mini Mag has had 18 different power combinations. I can’t
bothered with landing gear, it hangs up on too much at interesting places to fly.
The fall of 2009 I attended a regional meeting of a hundred pilots and their foam airplanes on the
Rhine River in Germany. There was only one other builder that was using fiberglass to reinforce
the foam, and then only to repair the nose of a Mini Mag. Another pilot and I compared hot
roded Twin Stars by flying them together. His hardware and battery investment was more then
twice mine, if the transmitter was included four times as much. I use outrunner motors and 6.6
X 3 inch props compared to his higher revving inrunner ones with 5 inchers. The better
efficiency of the propellers more then evened out the weight disadvantage of my NiMhs batteries
verses his LiPos. His was the faster one after gaining speed in level flight, it handled and glided
better. Mine accelerated quicker, climbed and dove better. Then, just to check, we swapped
airplanes and, since his had an elaborate radio, radios too. The performance difference then
was bigger, despite the better servos and motors in the other airplane the pilot is still a factor.
The pylon race with a dozen Twin Stars for the most laps in six minutes was hilarious. Where
that being able to tune the servos with the transmitters computer verses my mechanical
configuration mattered was at the ailerons and with wind. With full tuning of the servos the
airplane can be held in a vertical circle, as it is I am flying a spiral like the threads on a screw in
the wind. The other pilot had an awful time with my non linear controls, at first. I liked the
paint scheme on his, he shuddered when he realized what the entry 410 written on my wing
meant. My wing with fiberglass is more durable then his as is the work on the fuselage, even if
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you can see the tape and mud through it. Mine would fly better, and be easier to fly with a more
capable radio, but the difference wouldn’t be that much.
The hit of the show was a nominally hundred dollar Multiplex foam twin pusher airframe,
equipped with a USD 2500- jet engine. It’s not that we can’t duplicate the performance with
modern electric combinations, but nobody gets out of this life alive.
Go live a little, go fly.
Why, if I also can fly a “real” airplane i.e. one I can sit in, do I still fly “model” airplanes by
radio control:
My father and I keep a Piper Pacer built in 1954, a nominally 4 place private airplane, high
wing, 4 cylinder motor, the wings are fabric covered as is tail and fuselage back of the
passenger compartment, at the airport in Corona California. Our plane was refitted with a 140
horse power 4 cylinder carburettor engine and the hydraulic variable pitch propeller originally
installed in a twin (model Apache). That combination was also offered by the factory in later
years. I do not like the aeroplane. I am not fascinated with everything that flies just because it
can take to the air.
The PA-20 has a short wing (hence the name Short Wing Piper) with a simple rectangular outline
flat bottom airfoil about like a model airplane Clark Y. The wings main attribute was being
cheap to manufacturer and easy for a student pilot to handle. Ours were improved by “drop”
extensions that add a foot and a half to the wingspan but the main improvement is better control
on landing at near stall speeds. It is not inherently stable at cruise altitude although it does
handle well right at ground level, it has a higher then average fuel consumption. To me it’s
refusal to fly straight and level is irritating, I personally am not going to be landing on sand bars
in Alaska ever again. I am broad shouldered and only just fit in the cockpit. Fuel consumption
at cruise altitude of about 7000 feet and 120 mph is about 13 gallons of 80/87 octane aviation
gasoline per hour. At four dollars a gallon that works out to $52 an hour. Gasoline represents
about a third of the cost of using the airplane.
A new neighbour had a more modern Piper, a Cherokee (nominally a 4 place private airplane,
low wing with retractable landing gear, all metal) built in 1965 with the same engine. One of
my complaints about our Piper is that the muffler is about the size of a five pound coffee can, all
there is between the passengers and the engine compartment is a thin piece of aluminium, the
airplane is loud. His engine has a bigger main muffler and two separate mufflers and a double
firewall. With the high wing of my airplane what I see in the looking forward is a slim triangle,
80% of my visual field is the instrument panel. In the low wing plane I feel like I am sitting in a
chariot blasting through the air with a panoramic view. While comparing under the hood (cowl) I
realised that the owner/pilot was a good enough businessman to afford the thing, but did not
have a real grip of technical things, was probably not all that proficient a pilot, and didn’t know
it.
The airport at Corona has a smooth pleasant runway, three thousand feet long, that is wide and
flat. The usual approach is from the east, at the west end it trails off into a lake/emergency
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collection area that is a swampy forest and Lake Prado. There is no control tower. To the south
are hangers, to the east dry forest. The airport is subject to occasional fog. On a foggy morning
my neighbour with the Cherokee and a passenger took off facing west headed somewhere. That
is regarded as reasonable as normally the airplane climbs out of the fog and continues on it’s
way. This time, audible to, but not visible to, people present on the ground at the airport the
engine went to full power at mid-runway about a hundred yards in the air. At that position the
pilot had no other reasonable choice but to keep it headed straight and climb out, we suspect that
the gauges that were his only reference in the fog quit (quit possibly the vacuum pump that
drives them failed) and he went to full throttle while he lost all orientation until the airplane
slammed into the trees. Using a helicopter for the search they found the burned remains
scattered in pieces at sundown and didn’t even try to get there until the next day.
That vacuum pump is a sore spot in general aviation. The lawyers were particularly effective at
getting rich suing the light plane manufacturers, for a while they just quit making small
airplanes. The national agreement that they did not sell an airplane to last forever was breached
by the family of a Midwest state governor that probably killed himself by being a poor pilot in
marginal weather. As a result there will never be any new or repair parts for vacuum pumps ever
again, nobody will touch them. The cost to replace the vacuum powered instruments included
an entire new instrument panel and certification. That Cherokee that crashed had a marked value
of about $20,000- if you had to pay somebody to replace just the instrument panel that’s about
what the bill would be.
The fabric landing gear covering of our Pacer was raged and had to be replaced. I did as much
work as possible, the fabric and paint (it’s poisonous as a mixed fluid or aerosol), covering and
sandblasting I had done. The world’s best source of replacement and new parts for light and
experimental aircraft. Aircraft Spruce, is four miles from the hanger and there was a fixed based
operator at Flabob Airport only twenty miles away that still does fabric. I also replaced the brake
hard lines underneath the covering and instilled four new rubber bands that hold the plane up.
The net real cost was (40) hours of my time and $750- in cash. That doesn’t include the broken
knuckle of a boat mechanic friend that mistakenly thought airplanes demanded as much force as
boats and hammered the split rim wheel apart before I could get him to stop. Or my already
having the necessary tools, being able to scrounge up enough support frames and finding the
right people to get things done. I sometimes helped a retired developer restore a similar airplane.
Since our Pacer is currently worth about $7,000-, the best of them go for $18,000- and even
without replacing the instruments or installing radios that make flying it under today’s crowded
air I estimate the expenditure required to get it legally flyable again at (400) hours and $10,000in cash...
It takes about three to five thousand hours of time to build a new small airplane from it’s
component parts. At the airport in Corona there are at least a dozen builders, since I couldn’t
afford a place in both Germany and California I wound up at our hanger often. On my
meandering around on my bicycle I sometimes look in at their works. I feel jealous at their
ability to work on their own, among my faults I’m not self starting. Left to myself I spend the
day at the beach, fly my little radio control airplanes or go wandering. But all it takes to make
me go to commercial speed is people working around me.
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I spent five years using computer controlled machines to cut aircraft hydraulics. Then I was a
civil structural design engineer. Until the work ran out I used to be in on building schools and
hospitals. I also used to weld, including stainless steel both by hand and with computers. A
while back I did the motor mounts for a gas turbine single seat helicopter. The builder noticed I
was looking at his frame work and transmission way too intently... A neighbour across from me
at the airport, the bisexual lawyer (that’s not fair!), needed some help overhauling his extra 300,
since I was just sitting there watching a movie... I hadn’t seen my former brother law in
thirteen years (last words from his sister; Take your dog, your cat and your horse with you!)
after three other guys tried I finally had his Stearman biplane flying straight. When the old guy
just walked in my hanger to check out my Piper, he was served lunch (beans and rice with
venison) and I went over to his hanger to help him with his. The group that accumulated there
(including a former MD 80 airline pilot restoring a WWII era Piper) only complaint about the
lobster was that there was never enough, but some of them declined the curry(s). As it turns out
pilots are not only the only people that reliably follow directions, they are also discriminating
food critics, the food being just good isn’t enough for them, or me.
So, when the group building a second half size Feisler Storch needed somebody to help with the
conversion from a two cylinder two stroke motor to a four cylinder four stroke one they were
recommended to contact me. “What, that derelict wandering around on the red bicycle?” . Yes,
they all reported, next time he drifts by walk out and grab him, he just needs a push to get
started. So, a few days later I was surrounded by five men who grabbed me and pushed me off
of my bicycle. Professionally I am noted for being meticulous and ruthlessly pragmatic, if short
on elegance. They were dismayed at being pushed to work in a more organised manner. I was
not satisfied with the state of the plans either and spent days bringing the drawings and
specifications in conformance with industry standards.
A similar conversion already approved by the FAA was secured as a model for their project, I’m
not into reinventing the wheel. When the FAA inspector came to approve the conversion he was
able to point to exactly the areas where a professional had laid hands on the project, the airplane
was accepted, the documents were forwarded to the engine manufacturer in the Czech Republic.
They realised afterwards that they were getting more done for their time spent at the hanger.
That two days we spent with the airplane on supports verifying the balance were worth it, it flew
without trim. The original calculations were as valid as the information I was given, but, the
motor had to be positioned differently then first expected. For certification the weights were
adjusted to the actually measured ones.
But I don’t want to focus that hard on my little flying toys. By the way, my standard fee for
working on your stuff is a large pizza with everything on it, minimum cost $20. If you are
planing on eating too, get yourself something.
Ende
Other published works by the same author:
Using Spherical Geometry in CNC Machining; A Transfer of Coordinates, a Reduction in Data
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The Social Order of Construction Workers, A Guide for Professionals
Cumulative Allowable Tolerances in Layout, A Reminder to Architects and Engineers
Fit-up and Tolerances in X Braces, Why they don’t Fit
Places to Shoot Bier Cans and Party in Blyth California
Tijuana’s River Zone, When Dancing, Theater and Horse Riding Still Won’t Get You
Visions of the American West, 1001 Nights in a Van without a Campground
Looking for Lobster in all the Right Places, a Guide to Shallow Water Hunting
Translations: The Rheingau, a Guide for Americans to the Past and Present
The Boat (Das Boot)
The Revolution (Die Revolution)
Bonaparte’s Balloon (Ballon Bonaparte)
The Case of the Lorelei (Der Fall Lorelei)
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