Naval Arch/Stability

Is the GM large or small when a vessel has severe racking stresses?

Large

Is the GM large or small when a vessel provides a comfortable ride for the crew and passengers?

Small

What is it called when wind has caused a difference between drafts starboard and port?

Heeling

Define Listing

cargo causing a boat to lean to one side

An unstable upright equilibrium position on a vessel means that the metacenter is…

At the same height as the center of gravity

An upright vessel has negative GM. The vessel becomes stable at the angle of loll beacuse the…

effective beam is increases causing GZ to increase in either direction.

Assuming an even transverse distribution of weight in a vessel, which condition could cause a list?

Empty double-bottoms and lower holds, and a heavy deck cargo.

What is GZ?

Your righting arm

How many pounds is a long ton?

2,240 lbs

What is KG?

Height of the center of gravity

What is reserve buoyancy?

Volume of the vessel that isn’t underwater 

What is fresh water allowance?

How much the draft can change from fresh water to seawater and vice versa

Define Loaded displacement

total weight of the ship when it is loaded down to its summer load line

Define Deadweight

Difference between light and loaded displacement

Define Angle of loll

A list that is caused by negative GM

What does the free surface affect do to GM?

It reduces

Transverse stability

Balance side to side, if unbalanced we have a list or loll

Longitudunal Stability

balanced fore and aft, if unbalanced we have trim

Reserve Buoyancy

volume of watertight portion of ship above waterline

How do you measure reserve buoyancy?

Freeboard

Surge

Ship moves forward and back

Roll

When the ship rotates on a longitudinal axis

Heaving

Boat being pushed up and down

Yaw

Ship spins

Sway

Moving along horizontal axis

Pitching

When the boat goes up and down

Pounding

When bow slams into the waves

Panting

When the plates get pushed between tha frames

What causes panting and pounding

Pitching