Ship Manoeuvering Principles and Pilotage Flashcards

1
Q

The speed at which you can safely go astern on the engines is generally?

A

5 kts on a fully laden ship

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What rules of thumb should you use to judge speed?

A

1 knot = approx. 100 FT per minute or 30 Meters per minute (0.017 NM per minute when using a VRM)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When going astern and the ships head does not swing in the direction you expect due to the transverse thrust, this could be caused by the follow?

A

Wind effects or tidal stream effects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How can you create maximum transverse thrust effect?

A

By using Full ahead or Full astern, to create confused water around the propeller

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How can one minimize transverse thrust effect?

A

Build engine speed slowly by stages, so as to build up water through the propeller, so that it can gain maximum grip of the water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How much rudder is generally used to counter the transverse thrust effects?

A

Generally pretty negligible, only will need 1 or 2 degrees to counter its effect.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

If there is not enough room to turn a ship round in one single maneuver, then the ship will have to be turned__________.

A

Short Round

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which direction should a right handed propeller ship be turned to when turning short round?

A

Starboard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which direction should a left handed propeller ship be turned to when turning short round?

A

Port

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where will the center of turn be positioned when the ship is on an even keel

A

approximately midships

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where will the center of turn be positioned when the ship is down by the stern?

A

move further aft

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where will the center of turn be positioned when the ship is down by the head?

A

Move further forward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Do thrusters if fitted affect the center of turn?

A

NO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Do the rudder and propeller effect the center of turn?

A

Only if there is a change in ships speed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Will weight on a mooring line or anchor chain, alter the position of the center of turn?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Do tugs pushing and pulling alter the position of the center of turn?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

When the portion of the weight of the ships inertia and the power of the tug approaches being equal, then the ships center of turn will__________________

A

virtually be at the point where the tugs force is positioned

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define “drifting moment, and movement element”

A

Consisting of the moment between the point of balance of the wind force, and the point of balance of the under water resistance, which is mainly determined by the ships trim; combined with the leeward movement of the ship

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Define “wind force moment”

A

Between the point of balance of the wind force, and the ships center of turn, which varies according to the ships speed through the water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define “drifting movement”

A

the movement of the whole ship to leeward

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Define “ wind force point”

A

Is the point where the force of wind blowing on the ships side, including the superstructure and any deck cargo, is balanced or centered and will be somewhere on the ships surface. The wind force point will change or move if the relative direction of the wind changes, due to a change of the ships speed and or an alteration of course.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Define “ wind resistance point”

A

of a ship, resisting the drifting movement due to the wind, is the point on the leeward side of the underwater section of the ship, at which all resistance moments balance. Only if the relative direction of the wind changes, so will the wind resistance point, resisting the force of the wind change.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Define “ drifting moment lever”

A

the distance between the wind force point and the wind resistance point, measured at right angles to the direction of the wind.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Define “Drifting Moment”

A

is the product of multiplying the drifting moment lever, by the force of the wind. It is the moment that turns a ship, when drifting, onto the heading with the wind force point and the wind resistance point in line with the direction of the wind, it is when effect of the wind force, against the resistance of the underwater part of the ship is balanced.

25
Q

Define “ wind force lever”

A

is the distance between the wind force point and the ships center of turn and if it is the initial center of turn, then it will be the “initial wind force lever”

26
Q

When the wind is from abaft the beam, as the ship slows down, then the relative wind strength __________

A

Increases

27
Q

When the ship is trying to turn due to the combined effects of ‘drifting moment’ and the ‘wind force moment’ how can this be assessed?

A

By how much port or starboard rudder is being used to carry the ships current heading.

28
Q

When making an approach with a following wind you should?

A

start reducing speed in plenty of time, reduce speed slowly as to keep as much thrust from the propeller onto the rudder as possible.

29
Q

What are the two ways you can change the relative direction of the wind on a ship and the effect of the wind?

A

altering ships speed or course, or a combination of both

30
Q

When berthing stern to tide what should you make the fore and aft officers aware of?

A

You will want the stern to come alongside first and not to heave on any lines forward until so instructed.

31
Q

As you gather stern way, what effect does that have on center of turn and transverse thrust effect.

A

center of turn will move aft, reducing the transverse thrust effect.

32
Q

Using an anchor on loaded Ships up to __________ Gross or empty ships up to ____________ Gross, providing the nature of the bottom is suitable like soft mud and sand is pretty routine nowadays

A

10,000 and 15,000. anything above that size runs the risk of breaking the anchor chain if there is current or a strong wind blowing.

33
Q

If there is no current or wind, then with care, an anchor can be used safely on ships ____________ gross

A

30-40,000 Gross tons

34
Q

When can anchors not be used?

A

bottom is unsuitable, restrictions due to pipes cables etc, entering lock gates.

35
Q

How can you check there is enough weight on the anchor?

A

by stopping the engines, if the ship starts turning towards the anchor, and also if the ship starts to loose way

36
Q

When using a radar VRM to measure distance off the berth to drop the anchor, what must you take into account?

A

Allowances for the distance between the anchor and the ships radar scanner.

37
Q

If a tug is towing on the starboard bow and you want it to tow on the port bow, to get from the starboard bow to the port bow the tug will apply some force in the _______

A

opposite direction that you want, so that it can make it to the port bow.

38
Q

In order of precedence which tug would you place forward on a towline? Conventional- Voith- Z drive

A
  1. Conventional
  2. Voith
  3. Z drive ( only use forward if you have no other type available)
39
Q

In order of precedence which tug would you place aft on a towline? Conventional- Voith- Z drive

A
  1. Z Drive
  2. Voith
  3. Conventional.
40
Q

Gob lines are used on assist tugs to?

A

help reduce the chance of girting, however they can also make the tug virtually impossible to steer.

41
Q

A major draw back to thrusters is?

A

they only supply their maximum effect when the ship is stopped.

42
Q

When maneuvering a ship using a thruster it is important to keep in mind where the _______________

A

center of turn is

43
Q

When maneuvering by radar and making your final approach it can be hard to judge?

A

ships speed over the ground, and any set or drift

44
Q

When anchoring a ship accurately use a radar that is?

A

Gyro stabilized and in North Up relative display

45
Q

To make a basic passage plan for a deep draft ship first you have to?

A

identify all the shallow points on the route, then decide on the amount of underwater clearance for the speed of the ship.

46
Q

When experiencing a set and/ or drift across a channel, while navigating or approaching relatively narrow channels, when making course changes you should?

A

Make larger alterations of course then necessary to just balance for the set and drift, so that you not only maintain your required course but get back onto your original track.

47
Q

When trying to identify a ship via VHF what is the very least information you should give to identify the ship.

A

ships position and what direction it is heading.

48
Q

Using the rudder hard over in ether direction back and forth to slow a ship down is sometimes referred as?

A

rudder cycling

49
Q

A fairly average modern ocean going ship today will have a length ___ to ___ times its beam and a loaded draft about ______ to _______ of its beam

A

6 to 7 times

1/2 to 1/3 of its beam

50
Q

True or False: Spring tides are bigger than neap tides?

A

True

51
Q

When navigating through estuary channels, more care is needed during spring tides because?

A

Any tidal set across channels will tend to be more pronounced, especially at high water when there is more room for the water to flow over the banks.

52
Q

As a rule of thumb spring tides start?

A

about 2 days before a new or full moon, and last until about 5 days after a new or full moon.

53
Q

If you are berthing a ship at the time of H.W or L.W, but especially at H.W and the berth is not a solid wharf, but a berth built on piles, so that the water is allowed to flow freely underneath it, then there is a risk you will be set?

A

off the berth unless there is a special geographic reasons, like a bend in the river.

54
Q

How much a ship squats depends on?

A

the lines of the ships underwater hull, her draft and speed, the depth of the water under the keel.

55
Q

What are the four indications that a ship is steaming to fast and squatting and that there is insufficient under keel clearance?

A
  1. the ships starts sheering off course unexpectedly
  2. increased vibration from the propeller
  3. stern waves getting steeper and the tops of the waves breaking
  4. a reduction in the propeller revolutions, with the consequent reduction in speed.
56
Q

Drag is?

A

the accumulation of all the different forces acting on a ship in shallow water.

57
Q

If you are maneuvering a ship with very little UKC then the ships behavior will be unpredictable because?

A

of the pressures that build up between the ship and the bottom.

58
Q

If you go aground on a falling tide and cannot get off, then make sure to remember to?

A

Drop the anchor to stop the following rising tide carrying the ship further onto the bank, take soundings all around the ship to find out what effect that falling tide might have on the ship .

59
Q

It is always a good policy to check?

A

the ships heading against the gyro compass before leaving a berth.