SAMS Vessel Stability and Naval Architecture 2

Question 1

The angle of loll occurs when:

Accepted Answer

A vessel with negative initial GM finds a heeled equilibrium position

Answer

Angle of loll is the angle at which an initially unstable vessel (negative GM) heels until buoyancy geometry provides just enough righting moment to balance gravity, creating a heeled but momentarily stable position.

Question 2

Reserve buoyancy is best described as:

Accepted Answer

The intact watertight volume of the vessel above the waterline

Answer

Reserve buoyancy is the watertight volume above the current waterline that can provide additional flotation if the vessel takes on water or is overloaded, delaying or preventing sinking.

Question 3

The longitudinal center of gravity (LCG) is primarily used to calculate:

Accepted Answer

The vessel's trim (fore-and-aft inclination)

Answer

LCG is compared to the longitudinal center of buoyancy (LCB) to determine whether the vessel trims by the head or stern; when LCG is forward of LCB the vessel trims by the head.

Question 4

The downflooding angle is the angle of heel at which:

Accepted Answer

Water begins to enter the vessel through non-watertight openings above the waterline

Answer

The downflooding angle is the heel angle at which seawater can enter through deck openings, ventilators, or other non-watertight closures, rapidly worsening stability and risking foundering.

Question 5

A GZ stability curve with a large area under it indicates:

Accepted Answer

Good dynamic stability and strong resistance to capsizing

Answer

The area under the GZ curve represents dynamic stability—the energy needed to capsize the vessel—so a larger area means greater resistance to being capsized by waves, wind, or 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 2