Answers to Check your Progress
Questions
Section 1 – Cable – Rope, Wire and Chain
1
List the three main types of ropes used in the marine environment.
The three main types of rope are:
2

Natural fibres

Synthetic fibres

Steel wire ropes
Natural fibres have some advantages over the other types of ropes. List these
advantages.
Natural fibres are often used in life saving appliances because of their elasticity. They
do tend to warn users when they are under strain (they part with some sound warning).
Deterioration of natural ropes is easy to detect.
3
What are the most popular types of synthetic fibres that are currently in use in the
marine environment?
The most popular types of synthetic ropes are:
4

Polypropylene

Nylon

Kevlar

Silver rope
Compare these with the natural fibres mentioned in question 2.
Synthetic fibres are cheaper than natural fibres. Except for Kevlar. They float and
resist to UV radiation. They also have good elasticity and are quite strong.
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5
Explain how is a wire rope described.
A rope is described by its construction and the material it is made of. The diameter of
the rope gives an indication of its size.
Wire ropes are described by the number of strands that make the rope together with the
number of fibres that make up each individual strand. Here also the diameter of the
wire is stated in millimetres.
6 What are the advantages and disadvantages of using wire rope in the marine industry?
Advantages of steel wire ropes:

Strength

Big range to choose from

Do not suffer from solar exposure

Not easily damaged
Disadvantages:
7

Affected by the marine environment

Need greasing

Not always easy to handle

Can be quite expensive
Explain how you would cut a piece of fibre rope from a coil.
Before cutting a rope, whipping should be made on both sides of the rope to prevent it
unlaying.
8
How would you lubricate a wire rope?
Lubricating a rope: Clean the rope first with a wire brush to remove old and dry grease.
Apply grease to the wire making sure that the inside of the rope will also be lubricated.
Remember the safety precautions to take. This is discussed in another section.
9
Explain how you would secure a rope that will have to be released when under tension.
The rope should be secure with the used of figures of eight, possibly around cleats or
bitts. This will allow the rope to be released gently while the weight is taken by the
cleats or bitts.
2
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10 You have to prepare a space to store some ropes. Explain how would go about it.
Preparing a space for storing ropes:

Store ropes on gratings

Store away from chemicals.

Avoid exposure to paint and sunlight.

Avoid exposure to a wet/moist environment.

Have a well-ventilated space
11 Describe how you would inspect a rope for internal and external damage.
Inspecting a rope for internal and external damages:

For external damages, look for broken strands, look at the diameter (whether it is
reduced), look for signs of crushing or flattening. Also look for lack of grease or
other lubricant.

Have a good visual inspection of the rope.

For internal damages, open the wire rope for an internal inspection. The core of
the wire must be in good condition. Do not use and sharp metallic object to twist
the rope.
12 List six things that you must not do when using chains.

Six things not to do with chains

Not use them when they have knots.

Not use around sharp corners.

Not exceed their SWL.

Not use if links are damaged, worn or elongated.

Not drag from under load.

Not use when joined by bolts or bull-dogs.
13 How would you detect damage to chains?
Detecting damages to chains:

Look at the links for breakage, signs of unusual wear and tear and elongation.

Measure the diameter of the links.
14 What precautions would you take when making a stopper?
Precautions when making a stopper:
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
Use the correct stopper

Use a cow hitch

Stand away from the rope under strain
15 What are the factors that may cause deterioration of a natural fibre rope?
Factors causing deterioration of natural fibre ropes:

Water

Sharp edges

Chemicals

Sand or other abrasive material

Paint

Poor ventilation
16 How would you recognize signs of deterioration in a natural fibre rope?
Signs of deterioration of natural fibre ropes:

Abrasion

Cuts

Parting of outer fibres

Discoloration

Mildew

Rot
17 What are the factors that cause deterioration of a steel wire rope?
Factors causing deterioration of steel wire ropes:
4

Improper care (lack of lubrication)

Sharp edges

Sharp angles

Chafing

Exposure to salt water and chemicals

Improper handling

Excessive load
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18 How would you prevent a steel rope from deteriorating?
To prevent a wire rope from deteriorating:

Proper lubrication

Proper stowage

Proper handling

Never exceed its SWL

Regular inspection
19 A badly maintained synthetic rope can cause accidents. How would you care for these
types of ropes?
Synthetic ropes are subject to the same factors as natural fibre ropes. They must be
stored in a dry, well-ventilated space, away from excessive sunlight exposure. They
must not be surged on drums as the fibres will tend to melt. Exposure to chemicals and
paint will also affect synthetic ropes. Chafing must be avoided.
20 What are the signs of deterioration in synthetic ropes?
Signs of deterioration in synthetic ropes are:

Discoloration

Broken fibres

Powdery surface

Crispy noise when twisted
21 List the safety precautions you would take when using fibre ropes.
Safety precautions when using fibre ropes:

Do not exceed its SWL

Know the rope’s limitation

Avoid sharp bends

Not using ropes with knots and kinks

Rope inspected before use

Not standing in the bight of the rope

Not surging rope on drums

Not applying sudden loads
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22 List the safety precautions you would take when using wire ropes.
Safety precautions when using wire ropes:

In addition to above

Wear safety gear

Do not expose rope to chemicals etc

Use correct size sheeve, block or thimble

Correctly uncoil wire rope
23 What measures would you take to prevent a rope being overloaded?
Measures to take to prevent rope being overloaded:

Never exceed the SWL.

Take into account any reduction in strength of the rope. This could be due to
knots, kinks or excessive wear and tear.

Always allow for an extra safety margin if in doubt.

Check the weight to be lifted.

Make sure that the rope is suitable for the task. Eg one or more mooring ropes can
be under more strain than the other ropes when a vessel is surging along a wharf if
all of the mooring ropes are not under equal tension.
Section 2 – Cable – Knots and Splices
No Check your Progress questions.
Section 3 – Cable – Breaking Strain and Safe Working Load
1
Why do we need to know the SWL of any rope?
The SWL of a rope is a very important piece of information. It tells us the maximum
weight that the rope can lift without fear of breaking. Without the SWL, one would be
guessing as to how big a load a rope could lift. This of course would lead to many
accidents. The SWL also allows for a safety margin. Thus as its name implies it is the
maximum load that can safely be lifted by any piece of equipment. This of course,
provided the rope or equipment is in good working order.
2
As a rule of thumb, what are the strength factors used for some synthetic fibres that
you know?
Strength factors are:
6
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
2 for natural fibres

3-5 for synthetic fibres
What is the relationship between SWL and BS?
SWL is a proportion of the BS of any rope. Thus the BS is the ultimate load that the
rope can tolerate. A fraction of the BS is considered to be the safe load that should be
applied to the rope.
4
What is the BS of a 22mm nylon?
BS of 22mm nylon = SWL x 6
SWL = 3D² = 3 x 22 x 22
BS = 3 x 22 x 22 x 6 = 8712kgs
5
What is the BS of a 14mm SWR?
BS of 14mm SWR= SWL x 6
SWL of SWR= 8 x 14 x 14
BS= 8 x 14 x 14 x 6 = 9408kgs
6
What is the SWL of a sisal rope whose diameter is 16mm? Could you use that rope to
lift a load of 250kg?
Sisal rope diameter 16mm
Breaking strain of sisal= 2D²/300
B.S
SWL
=
(2x16x16)/300
=
1.71T
=
1.71/6=.284T or 284Kgs.
Yes, the weight can be lifted.
7
You need to lift a load of 450kg using a nylon rope. What is the minimum size of rope
you would use for the operation?
The ropes SWL must be at least 450Kg or.45T
The B.S must then be:.45x6=2.7T
The B.S of nylon is 5D²/300
Therefore 5D²/300 must be equal to 2.7T
Solving the equation we have:
D²=162
D= 12.7mm or 13mm
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Section 4 – Cargo Handling and Deck Machinery
1
State how you would service a block
Servicing a block. Dismantle, check all parts for wear and tear. Check for distortion,
signs of uneven wear and for rust. Clean all parts. Grease and re-assemble. Again
check for all moving parts.
2
What do you understand by the term rigged to advantage?
Rigged to advantage means that the hauling part of the rope comes from the moving
block.
3
Would a purchase that is rigged to disadvantage still have a mechanical advantage?
Yes, it would still produce a mechanical advantage. However the tackle could be
rigged to produce an even better mechanical advantage, thus requiring a smaller effort
to lift the same load.
4
List six general lifting precautions you would take.
Safety precautions:
5

Never exceed the SWL of the gear.

Be careful when lifting heavy load.

Avoid swinging the load.

Avoid sudden jerks on the gear.

Do not pass load over personnel.

Listen to the gear.
Explain the ship’s movements likely to affect the securing of any item on board a
vessel in a seaway.
The ship’s movement that affect cargo is known s the six degrees of freedom. They are
rolling, pitching, swaying, heaving, yawing and surging. Out of these, rolling, pitching
and to a lesser extent heaving affect the movement of cargo stowed on board. Yawing,
surging and swaying when compounded with the first three also affect the securing of
the cargo.
6
What precautions would you take when securing?
Precautions to take when securing:

8
Proper securing equipment
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
Secure the load having analysed its possible movement.

Securing point strong enough to take on the load.

Secure for the worst sea condition.

Secure in such a way that the cargo can be jettisoned if necessary.

Consult the Cargo Securing Manual if vessel falls under AMSA’s and/or SOLAS
legislation.
List the safety principles you would observe when contemplating lashing on board.
Safety principles to be observed when contemplating securing:
8
9

Movement of cargo, if any, not to cause harm to people and vessel.

The use of shores, braces, dunnage in addition to conventional lashing equipment
such as wire ropes and turnbuckles.

Load not to be overhanging.

Weight of cargo to be evenly spread over the deck.
Differentiate between bracing, blocking, shoving and tomming.

Differentiate between bracing, blocking, shoring and tomming.

Bracing involves the application of FORCE in a horizontal direction. Blocking
involves placing timber against the sides of a load.

Shoring means to support from underneath. Obviously the shoring material must
be able to support some if not all of the weight of the load. And tomming means
holding a load down. The action of tomming is to counteract heaving.
What are the characteristics of the cargo that affect its possible movement in a
seaway?
Characteristics of cargo that affect its movement:

Weight

Size

Density

Position of center of gravity

Shape of cargo
Additionally, the location where the cargo is stowed
10 What are the checks you would normally carry out prior using derricks?
Checks to be carried out are:
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
The booms are correctly positioned.

The guy pendants and preventers are properly secured.

All the shackles are properly moused.

All moving parts are running smoothly.

The operator is conversant with the system.

The ropes and accessories are in good working condition.

Provides more comfort to the operator.
11 What are the advantages of cranes over derricks?
Advantages of cranes over derricks:

Saving on labour

Can lift bigger loads

Faster operations

Are versatile (can be used over two holds or in tandem)

Do not need to be prepared before use.
12 Would you think of some drawbacks of cranes?
Drawback of cranes:

Electronics can play up. Need experts to fix

If hydraulic, can have burst pipes spraying oil on deck.

Can cause ship’s list if not stowed properly.
Section 5 – Ladders and Stages
1
10
List the precautions for rigging a stage.

Check stage for defects.

Inspect all lines and fittings.

Correctly rig the stage.

Load test the stage to 4 times the intended load.

Gantlines must trail in the water to be used as lifelines.

Stages should only be rigged over water.

Do not use whilst underway.

Always set down before raising and lowering.

Rig a rope ladder for access.
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
2
Be positively tended and have a life buoy available.
Briefly list safety precautions for working in a bosuns chair.
The person working aloft should make sure all tools etc, have safety lines attached.
A safety precaution while in the chair is to have a harness attached to the standing
rigging of the vessel. This will stop you from swinging around when the ship moves
about. Always remember to tie all the tools you are using to the chair so that if one
slips from your hand it will not fall to the deck.
Section 6 – Watertight Integrity
1
What is the purpose of sills and coamings?
Sills and coamings raise possible water entry points above deck level so that if a hatch
is open when water comes on deck it is more difficult for the water to enter the
opening. They also have the effect of moving seals away from the majority of water.
2
What do you understand by ‘Watertight Integrity’?
Watertight Integrity is all about keeping the ocean on the outside. A vessel only floats
because of the water it displaces. The shell (skin) of the hull provides the watertight
integrity but that shell is penetrated or has openings to allow the working of the ship.
So Watertight Integrity covers the shell and how we deal with the openings to prevent
water filling the hole in the ocean that is our displacement.
Section 7 – Watchkeeping
1
Visibility reduces significantly. As OOW what actions would you take?
The first action is to call the Master (This will be in all standing orders). As OOW you
are responsible for taking all relevant action until the Master arrives. You should turn
on navigation lights and make sound signals if appropriate. You need to review the
composition of the watch and call any extra crew you might require to the bridge. You
may have to review primary and secondary methods of fixing the vessels position.
2
Describe the relationship between the Master, his OOW and a Pilot, and their
responsibilities.
The Master has ultimate responsibility for the safe conduct of the vessel. The OOW is
the Masters representative and as such takes much of that responsibility (as detailed in
standing orders etc) whilst he is on watch. The pilot is an advisor with specialist local
knowledge and becomes a member of the bridge team.
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The OOW has a responsibility to brief the Pilot and seek his input. However he retains
responsibility for the safe conduct of the vessel. If in doubt about any of the input or
actions of the pilot he should call the Master (As per the standing orders) and take
appropriate action until the Master arrives.
3
Describe in detail how you would take over the watch.
The relieving OOW should be on the bridge at least 15 minutes before the handover to
ensure that:

Their eyes adapt to the light.

They have time to read and sign the Night Orders.

Receive a briefing from the current OOW.

Identify all landmasses and targets that appear on the radar screen.
The briefing from the current OOW should include:

The vessel’s position.

The current course.

A description of any current that might be present.

The operational status of the vessel’s propulsion and steering machinery.

The operational status of all the vessel’s navigation equipment.

The location and a description of the movements of all traffic in the area.
The OOW should not handover the watch if he or she suspects that the relieving
officer is not fit for duty. The skipper must be called if this is suspected. The relieving
officer should not take the watch if:
12

He is not satisfied that the vessel’s position as given by the OOW is correct.

The vessel is in a close quarters situation or a close quarters situation is
developing.

The radar picture does not agree with the position and situation as described by
the OOW.
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