Shiphandling

Question 1

What is the main aim of Shiphandling?

Answer 1

BALANCE OF FORCE - these include controllable, uncontrollable and semi-controllable

Question 2

What are the Controllable Forces?

Answer 2

• Engines & Propellers
• Rudders
• Thrusters
• Tugs
• Anchors
• Mooring Lines

Question 3

What are the Uncontrollable Forces?

Answer 3

• Wind
• Current

Question 4

What are the Semi-Controllable Forces?

Answer 4

• Shallow Water Effect
• Passing Effect

Question 5

Describe “Transverse Thrust”

Answer 5

This thrust is also known as the Paddle Wheel Effect
This is where by as the propeller (fixed pitch) turns, it has the tendency to bring the stern to the direction of turn

Question 6

Describe “Cavitation”

Answer 6

Cavitation is the formation of vapor bubbles in water near a moving propeller blade in regions of low pressure

Question 7

How does a Rudder generate lift to turn the vessel?

Answer 7

There must be water flow onto the rudder to turn the vessel (can be from propulsion or current)

Question 8

How can you slow the vessel down using your Rudder?

Answer 8

By the method of Rudder Cycling - either HIGH or LOW frequency
- HIGH frequency: moving the rudder hard over to hard over quickly to create drag to slow the vessel down
- LOW frequency: moving the rudder hard over to hard over slowly (40 degrees off course to 40 degrees off course) for a more controlled decrease of speed

Question 9

Common Ship Handling terms?

Answer 9

Question 10

Factors effecting a turn?

Answer 10

Question 11

What’s view ahead?

Answer 11

Question 12

Describe how would you turn the ship short round (RIGHT HAND FPP)

Answer 12

Question 13

Who does interaction affect a vessel when moored?

Answer 13

1. Stern moves away from passing vessel’s bow (same forces repel)
2. As passing vessel proceeds, bow moves away from stern, making stern surge away
3. Passing vessel abeam - positive stern moves towards passing vessel due to positive bow forces meeting
4. As passing vessel’s beam meets with moored vessel’s bow, opposite forces attract and causes moored vessel to surge ahead

Question 14

What are the effective methods to reduce vessel interaction?

Answer 14

• Slow down
• Increase distance
• Find deeper water (interaction considered to start around 2x the vessel’s draught)

Question 15

What should be done before conducting any manoeuvre after picking up the pilot?

Answer 15

• Conduct effective Master Pilot Exchange
• Discuss the manoeuvre with the pilot
• Brief bridge team
• Brief mooring team (especially if lines have to be sent early, anchor to be used etc)
• Abort point agreed & contingency plan in place (weather deteriorate, berth not up to standard etc)