SAMS Vessel Stability and Naval Architecture 3

Question 1

The free surface effect reduces vessel stability because:

Accepted Answer

Liquid in a partially filled tank shifts to the low side when the vessel heels, raising the effective center of gravity

Answer

When a partially filled tank's liquid shifts to the low side as the vessel heels, the transverse shift of that weight raises the effective G, reducing GM and stability; this loss is quantified as the free surface correction.

Question 2

The Plimsoll mark (load line) on a vessel indicates:

Accepted Answer

The maximum permissible loading depths for various seasonal and geographic zones

Answer

The load line marks the maximum depths to which a vessel may be loaded under different sea conditions and seasons (tropical, summer, winter, freshwater, etc.) to ensure adequate freeboard and safety.

Question 3

In a vessel's stability booklet, the 'light ship' condition is defined as:

Accepted Answer

The completed vessel with no cargo, fuel, ballast, fresh water, stores, crew, or passengers

Answer

Light ship displacement is the weight of the vessel as built and equipped, with all machinery operational but carrying no cargo, fuel, lubricating oil, ballast, fresh water, stores, crew, or passengers.

Question 4

In naval architecture, 'trim' refers to:

Accepted Answer

The difference between the forward draft and the after draft

Answer

Trim is the longitudinal inclination of a vessel, defined as the numerical difference between the forward and aft drafts; a vessel trimmed by the stern has a greater aft draft than forward draft.

Question 5

IMO intact stability criteria for most vessels primarily require:

Accepted Answer

Sufficient area under the GZ curve across defined heel angle ranges to resist dynamic forces

Answer

IMO criteria (IS Code 2008) specify minimum areas under the GZ righting arm curve between defined angles of heel, ensuring sufficient dynamic stability energy to survive waves, wind, and cargo shift.

(SAMS) Society of Accredited Marine Surveyors Certified Practice Test

(SAMS) Society of Accredited Marine Surveyors Certified Practice Test

SAMS Vessel Stability and Naval Architecture 3