N/\sn
Aeronautics
and
National
SpaceAdministration
MR.41-B
Mission41-B:AloneIn Space
Gibsonwas makinghis first spaceflight,as were
BruceMccandless,
RonaldMcNair,
MissionSpeciallsts
and RobertStewart.
PayloadsAboardChallenger
payloads
for the 41-B'missionwere
Theprincipal
satellites:WesternUnion's
two communications
WESTARVl and PALAPAB-2,ownedby the Republic
of lndonesia.Also loadedin the cargobay was the
west German-built
shuttle Palletsatellite-sPAS-a
platformladenwith scientificinstruments
that alsoflew
on the STS-7missionin June1983,whenit was
releasedto fly free and then retrievedby ChallengeL
On this missionit was usedby the crewto practice
Spece Shuttte ,tiasion 4r-B tnlomal Portrait.
activities
duringtheirextravehicular
dockingmaneuvers
fromthelowerlelt are:Commander
Vance
Counterclockwise
(EVAS),
first
ever
to
be
The
satellite
or spacewalks.
Dr.
D. Brand,PilotBobertL. Gibson,andMissionSpecialists
also
carried
eight
flown
again,
SPAS
refurbished
and
ll andRobertL.
RonaldE. McNair,BruceMcoandless
for the FederalRepublic
of
scientific
experiments
Stewart.
Germany'sMinistryof Researchand Technologyand
for a satellilerepairmissionscheduled
lhe European
SpaceAgency.
Preparations
Target-a two meter(6.6
An IntegratedRendezvous
for the spaceshuttle'sApril 1984flightpromptedlwo
duringShutlle's41-Bmission.
foot)-wideMylarballoonstowedinsidea canister-was
spacewalks
untethered
Units(MMUs) alsocarriedin the cargobay for use in practicing
MannedManeuvering
Usingjet-propelled
crewflew
rendezvous
techniquesin orbit.In addition,therewere
two astronautstrcm Challenger's
of their motherspacecraftfor the first
two stowageassemblieswithtoolsand equipment,two
independently
anda 35
Challenger
MannedManeuvering
Unit(MMU)backpacks,
time,thoroughlytestingMMU capabilities.
the
millimeterfilm camerasystemusedto photograph
returnedto its Floridalandingsite for the firsttime.
spacewalksand othercargobay activitiesduringthe
Mostof the mission'smajorflighttest objectiveswere
is a joint
mission.
Thisproject,called"Cinema-360",
despiteseveralequipmentfailures
accomplished
The
endeavorof NASAand a groupof planetariums.
associaledwith hardwarelaunchedfromthe shuttle
special{ormatfilmwillbe usedin a motionpicture
cargobay duringthis tenth mission,extendingfrom
3 to 11,1984.
aboutthe shuttleprogram.
February
Roundingout the list of itemsin the cargobay were
Challengerand a crew of five were launchedfrom
five "GetawaySpecial"canisters,smallself-contained
KennedySpaceCenterat 8:00 A.M. on February3 into
a 305 kilometer(165nauticalmile)-high orbit,inclined
-.
28.5' to the equator.ln commandot Challengerwas
as'4"
und", n"nunrrbering system,ihis missionwasdesignat€d
the
firsl
operational
Brand,
who
also
commanded
Vance
" fiscalyearof launch)"1" (thelaunchsite-KennedySpace
(1984,the
for thatyear).
flightot the shuttlein November,1982.PilotRobert
Center)and"8" (thesecondlaunchscheduled
*
Mcoan.ttess Flys Solo in Space
AstrcnautBruceMccandlessll, SpaceShuttleMlssion41-B
MissionSpecialist,
is photographed
duringhishistory-making
untethered
ertravehicular
activity(EUA),on Februaty7, 1984.
Mccandless
becamethe firstpersonfromEarthto "fly"
tromhisspacecraft.
detached
ln the weightless,
airless
emptiness
of spacehe wascompletely
detachedlrom his
mother-ship
andbecamethetirstpersonto "solo"in space.
payloads,fixedto lhe righthandwall of the bay.These
experiments
in physics,
biology,
technology,
and
materialsscienceweresponsoredby GTE
Laboratories,
lnc.,the U.S.Air Force,NASA'S
Goddard
SpaceFlightCenter,and highschooland universtty
studentslrom Utahand the Universityof Aberdeenin
The experiments
Scotland.
wereturnedon or off by the
crewat different
timesduringthe missionandoperated
automatically.
pressurizedcabinwereseveral
lnsideChallenger's
moreexperiments
andcargoes,including
a second
"Cinema-360"
filmcamerausedby the crewthroughout
the missionto document
typicalactivities
onboardlhe
spaceshuttle.Eachol thesecameraswasequipped
witha 'fisheye"lensthatgivesa 180' x 360"fieldof
planetarium
viewsuitable
for showingon hemispheric
domes.
A Monodisperse
LatexReactorexperiment,
a
for makingmicroscopic
miniJactory
latexspheresof
uniformsizefor usein medicaland commercial
applications,
hasalreadyflownon severalshuttleflights
and was carriedon Challenger's
mid-decktor this
Thecrewturnedon the reactorapproximately
mission.
one day intothe missionand aftera run of 20 hoursit
turneditselfoff automatically.
Anothercargoexperiment
carriedinsidethe vehicle
involved
a newtechnique
for separation
of proteinfluids
by theirdiverseelectriccharges,a processknownas
electrophoresis.
An lsoelectric
Focusing
Experiment
waslocatedin a lockerin the mid-deck.
Forthe second
timein the shuttleprogram,
liveratswerecarried
onboardin an AnimalEnclosure
Module(lifesupport
cage).On this flightsix ratswerethe subjectsol a
studentexperiment
to studywhetheror not
weightlessness
relieves
the symptoms
of arthritis.
Two
moreexperiments,
onefor monitoring
radiation
levels
insidethe vehrcleandanotherfor processing
material
samplesin an Acoustic
Conlainment
Furnace,
were
alsolocatedin the mid-deck.
TwoSatellitesGo Astray
the shuttlecarried
As on severalearliermissions,
intospacefor launching
into
commercial
satellites
geosynchronous
orbit.The sequence
of evenlsfor
theselaunches
beginswhenthe satellite
is set spinning
turntable
in
lhe
cargo
bay.
lt
is
then
reieased
by
on a
springsto coastawaylrom the orbiter.Forty-five
minutesafterdeployment
the satellite's
attached
(PAM)
rockel
motorfiresto
PayloadAssistModule
solid
boostit from low orbitinto an ellipticaltransferorbitof
(160 x 22,300miles).Later
260 x 35,900kilometers
the orbit
anothersmallrocketmotorfiresto circularize
(22,300miles).
at 35,900kilometers
Usingthis technique,WESTARVl---onein a seriesof
satellitesusedby WesternUnionto providevideo.
voice,anddatacommunication
to the UnitedStates
and its territorieg-waslaunchedon time and on taroet
lrom Challenger
at approximately
eighthoursintoth;
mission.Soonafterthe deployment,
stationson the
groundtrackedtwo objectsin an egg-shaped
orbitof
1,1O0x 27Okilometers
(600 x 150 nauticalmiles)that
appearedto be WESTARVl and its pAM rocketmotor.
This was conJirmed
when a groundstationregained
radioconlactwith the satelliteon FebruarvS. lt
apparently
wasundamaged,
but hadfaile; to reachthe
properorbit.
Questionsas to why WESTARhad gone astray
forceda rescheduling
of the deploymenlof Indonesia's
nearlyidenticalPALAPAsatellitefromflightday two to
flightday four.When pALApAwas tina y launChed,
however,it too tailedto reachgeosynchronous
altitude,
and assumeda low orbitsimilarto WESTAR'S.
The
probableexplanationis that bothsatellitesexperienced
a lailurein the nozzleof their pAM rocketmotorsthat
.obbedthem of the thrustneededto reachthe
necessarytransferorbit.Meanwhile,both pALApAand
WESTARremainin the low,non-synchronous
orbits,
unusablebecauseol their radicallychangingpositions
in the skv.
Rendezvous
and Rehearsalfor SolarMax
Muchof flight41-Bwas devotedto testinonew
hardwareand proceduresfot Challenger's
riextmission,
a retrievaland repairof NASA'sSolarMaximum
Missionsatellite,whichhad a failurein its attitude
controlsystemlessthan a year afterit was launchedin
1980.On lhe repairmission,Challengerwill fly to within
90 meters(300feet)of the damagedsateltite.An
astronautflyingwith a MannedManeuverino
Unit
backpackwill leavethe orbiter,dockwith th-eslowlv
turningsatelliteand stop its motionso that the Remote
Manipulator
System's15 meter(50 foot)arm can
grappleit and placeit in the cargobay.Astronautswill
thenworkon the satellitein the bay, replaceits
damagedparts,and re-releaseit intoorbitwiththe
RemoteManipulator
System'sarm.
This importantmissionrequiresthat a numberof
proceduresbe rehearsed,beginningwith the
rendezvousitself.The orbiterhas severaldevicesfor
preciselysightingand trackingthe positionof other
objectsin orbit,includinga rendezvousradarsystem,
siar trackersusedfor obtaininga navigational
fix on
targetstars,and the CrewOpticalAlignmenlSight
(COAS),whichis similarto an aircraftgunsight.These
deviceswereto havebeen usedto trackthe Integrated
Rendezvous
Targetballoon.Thiswouldhaveoccurred
in a seriesol maneuversIn whichthe orbiterwould
releasethe balloon,moveas far awavas 270
kilometers(150nauticalmiles),then practiceapproach
techniques.Unfortunately,
the balloontore into
fragmentswhileintlating,shortlyafterit was released
fromthe cargobay,two days intothe mission.
Despitethe mishap,usefuldatawerestillcollected
and flightdirectorsgainedconfidencein the rendezvous
operations.The crewwas evenableto sightand track
a largesunlitfragmentof the balloonat unexpectedly
distantranges,and the radarwas ableto obtaina s;lid
lockon the targetout to 12,000meters(40,000feet).
FlyingFree:The MannedManeuvering
Units
Stewarl Teats Second Manned Maneuyefing Itnil
(MMU).
AstronautRobertL. Stewart flys "Solo"outsidethe Space
ShuttleOrbiterChallengerin the second seriesof
extravehicularaclivitiespertormedduring the 4l-B mission.
AstronautsStewartand Mccandless testedtwo Mmned
ManeuveringUniE during this mission.
On the mission'sfitth day, BruceMcCandless
and
RobertStewartbecamethe first peopleto fly in space,
free and detachedfromtheir vehicle.Duringnearlysix
hoursof extravehicular
activity,they successfully
tested
a jet-poweredMannedManeuvering
Unit (MMU)for the
firsttimein orbit.
TheMMUweighs136kilograms
(300pounds)and is
wornlike a backpackby a space-suited
astronaut,who
can put it on or removeit unassistedat a specialllight
supportstation,whichalso servesas a stationfor
re-charging
the MMU batteriesand the 24 small
nitrogengas thrustersthat directits motion.projecting
fromthe frontof the MMUare two arm-liketowers;with
left-handcontrolsfor movingforwardand backward,up
and down,and sideways;and right-handcontrolsfor
yaw,pitch,and roll.
McCandless
and Stewartmovedout intothe cargo
bay to test the MMUsin spaceafterundergoinga
periodthan any
shorteroxygenpre-breathing
in history,thanksto a techniquethat uses
spacewalkers
loweredcabinpressureto purgethe bloodof nitrogen.
Onceoutside,McCandlessimmedialelygot intohis
MMU,releasedit from its latches,and {lew awayfrom
the orbiterto a distanceof 45 meters(150teet),staying
in sightof his crewmateswatchingthroughthe
overheadwindowsfrom insidethe Challenger.
Mccandless
thencheckedout the MMU'smaneuvering
furtherby returningto the bay and moving
capabilities
awayagainto a distanceoJ96 meters(320feet)while
beingtrackedby the orbitefs radar.
WhileMccandlesswas test-flyingthe MMU Stewart
unstowedthe TrunnionPin AcquisitionDevice(TPAD)
lrom a SpecialEquipmentStowageAssembly(SESA)
box mountedon the cargobay wall.This portable
TPADdeviceallowsan astronautto dockwith another
soacecraftsuchas the SolarMaximumsatellite.lt fits
on the armsof the MMUand hasa cylindrical
endlor
lockingontograpplefixtures.McCandless,
still in the
MMUbackpack,practiceddockingthe TPADto a pin
protrudingfromthe siowageassemblybox to verifythe
TPAD'Soperation.
StewartTestsFootRestraint
Meanwhile,
Stewartcheckedout anotherpieceot
hardware,a Manipulator
FootRestraint(MFR)platform
thatfitson the endof the longmanipulator
arm,
allowinga crewmanto be movedaroundthe cargobay
whilestanding
on a stableplatformlikea telephone
line
repairman
in a "cherrypicker."Thecrewinside
Challengercontdled the arm'smotionwhileStewart
did a numberof teststo evaluatearm stressand the
stabilityof the platform.
Mccandlessand Stewartthentradedequipment,with
Stewartflyingthe MMUtwiceabovethe orbiter,then
practicingdockingthe TPADto anotherattachmentpin
locatedon the ShuttlePalletSatellite(SPAS)in the
bay.Meanwhile,Mccandlessusedseveraltoolsfrom
lhe stowageassemblybox to practiceworkingon a
mockupof the SolarMaximum
main
satellite's
electronics
box(alsolocatedon the SPAS)while
standing
at the endof the armon the MFRplatform.
Havingverifiedthat the MMUbackpackmaneuvered
as
it was designedto and that the MFRplatformis a
stableworksite,Stewartand Mccandlessre-entered
the orbiterafternearlysix hoursof extravehicular
activity.Morethantwo and a half hourswerespent
testingthe MMUbackpack.
the technologyof solarcells,heatpipes,and pneumalic
for analyzingtracegassesin
conveyors;a spectrometer
and aroundthe orbiter;an evaluationof a newtype of
spacecraftattitudecontrolcalleda Yaw EarthSensor;
and a remotesensingcamerathat recordedimages
over NorthAmerica,CentralAmerica,and olher areas
as lhe Challengerpassedoverhead.
On flightday seven,Stewartand Mcoandless
donnedtheirspacesuitsfor the mission'ssecondEVA.
One key test plannedlor the day was a dockingwith
the SPASsatellitewhileit was turningvery slowly(like
the SolarMaximumsatellite)on the end of the
manipulator
arm,whichwas to haveheldthe SPASup
and awayfromthe orbiterwhile BruceMcCandless,
in
an MMUbackpack,grappledit wilh the TrunionPin
AcquisitionDevice(TPAD).Afteran electricalproblem
was discoveredin the arms'swristjoint,the test was
canceledand Mccandlesspracticeddockingwith SPAS
and maintaining
a securelockon it whileit remained
anchoredin the bay.
BothMcoandlessand Stewartcheckedout a second
MMUin variousflyingand attitudehold maneuvers,
and
reportinglhat it alsoworkedwell.Duringtheseteststhe
astronautsevaluatedsuchfactorsas the abilityto stop
precisely,to hold a steadyposition,and to accurately
controltheirdirectionand soeedof motion.
A finalchoreon this spacewalkwas performedby
Stewart,who testeda tool for transferring
fuel from a
storagetank to a satelliteor fromone satelliteto
another,a servicingjob that may eventuallybe done in
the cargobay. Stewartfit the tool to a valvein the
StowageAssemblyBox,allowinga mixtureoi freonand
dyeto translerout of a container,muchas highlytoxic
hydrazinefuel wouldflow in an actualsatelliterefueling.
No dye was seenspillingtromthe valveand the
transferappearedto go smoothly.The systemwas to
be checkedfor leaksafterthe mission'send.
SuccessfulLandingin Florida
Aftermorethan six hoursout in the cargobay,the
two astronautsre-enteredChallengerand preparedfor
theirlasi day in orbit,a day ot stowingequipment,
turningoff experimenls,
and makingreadyfor the
shuttle's
lirsi landingin Florida.
Shuttleflighl plannerswantto landthe spaceshuttle
regularlyon the KennedySpaceCenter's4,572 melel
(15,000foot)landingstriplo savelhe iime and cost ot
returningthe orbiterfromthe landingsite in Calitornia.
Challenger
was scheduledto land in Floridaat the end
of the STS-7missionin June1983,but badweather
iorceda Californialanding.
A SecondSoacewalk
On February11,the weathercooperated.
On its 27th
The sixthday of the missionwas devotedalmost
revolutionaroundthe Eafth,Challenger's
Orbital
on the SPASplatform, Maneuvering
entirelyto scientificexperiments
System(OMS)engineswerefiredover
whichremainedanchoredin the cargobay. SPASis a
the IndianOcean1oslowthe vehicleand drop it out of
prototypeof a newtype of spacecratlthat servesas
orbit.An hourlater,CommanderVanceBrandbrought
powersupply,data processor,and temperatureconlrol
the orbiterto a smoothstopwith 690 meters(2,300
to a widevarietyof instrumentsat once.Theseincluded feet)of runwayto spare,and at 7:17A.M. EasternTime
two materialsprocessingexperiments
in Getaway
the tenthSpaceShuftlemissionended,only a few
Specialcanistersfixedto the platform;experiments
in
milesfromwhereit had beguneightdaysearlier.