Shiphandling Flashcards
When turning in shallow water diameter of the turn will ? By how much?
<p>Increase. By twice the diameter.</p>
What happens to rate of turn in shallow water verses deep water?
<p>Remains constant, though turning circle (tactical) diameter increases in shallow water.</p>
Is transverse thrust while moving ahead more noticeable on a small or large ship
<p>Small, until almost no effect on ULCC and VLCC sized ships.</p>
If accelerating will turning circle diameter be larger or smaller than at constant RPMs.
Smaller. (Rule of thumb: Starting DIW with turns for 6 kts, turning circle will be 1/2 size of circle starting at 6 kts with constant RPM)
At what speed through the water does a bow thruster become effective?
Two knots.
At what depth do shallow water effects take place?
Depth of 1.2 to 1.4 of draft
In shallow water does ship become more directionally stable? Steering improves?
Yes
Does turning circle diameter increase or decrease with shallow water effects?
Increase
Does the ship twist more or less when backed in shallow water?
More
Does a ship carry further or shorter in shallow water?
Further
What direction from the wind does the bow tend when backing?
Bow falls away and ship will back into the wind. Due to pivot point moving aft.
As a ship reduces speed it will tend to turn in what direction relative to the wind?
It will turn into the wind.
What creates the pivot point?
The couple between the forward momentum of the vessel and the longitudinal resistance created by the water.
Where is the pivot point when the vessel is at a constant speed?
Approximately 1/4 of the ships length from the bow.
How does the pivot point location effect turning levers?
The moment of force times the length to the pivot point creates the turning lever.