Trim, Stability, Stress. Test 1 – Online Maritime Tests

What are bending moments?

Forces affecting the fore part of the vessel.
Forces which bends the vessel up and down in the fore-aft direction (hogg/sagg). fore-and-aft direction (hogg/sagg).
Forces affecting between loaded and empty parts of the vessel.
Forces affecting the aft part of the vessel.

When planning the distribution of the cargo, what are the most important forces to take in consideration?

Only shear forces.
Only bending moments.
Shear forces and bending moments.
Torsion forces.

Which of the following requirements to ships stability for normal operation corresponds to present regulations? (NSCL 4/12.2)

I waters with the danger of icing, loading of deck cargo must be approved by competent authority.
The ship is loaded in such a manner that adequate stability is achieved in all loading condition.
Centre of gravity shall be calculated with an accurancy better than 5 percent.
Unless othereays stated in the approved stability calculation, the total weight of the deck cargo shall not exeed 50 metric tons.

In an OBO, if part liquid is present in any hold (say 60% by volume) this will give rise to 'sloshing' which is the movement of liquid when the vessel is rolling or pitching. Sloshing can cause:

Formation of potentially dangerous electrostatically charged mist if a mixture of oil and water (such as dirty ballast) is present in the tank or hold?
Structural damage to the ship's inter-hold transverse bulkheads due to the slamming effect of the liquid?
All the mentioned alternatives.
Structural damage to the ship's hull due to the slamming effect of the liquid?

What should be observed concerning a ship's water tight integrity?

The aft door locked
That all vessel's water tight ramps and doors are locked and secured at sea.
The ramp in stowed position
All emergency exits doors locked and secured

Which of the following requirements regarding on board stability data corresponds to present regulations? (NSCL 4/12.1)

Stability data produced by stability calculation instruments.
Drawings and caculations documenting the stability of the ship, both in intact and all possible damage condition.
A calculation example showing the use of 'KG' limitation curves.
A calculation example showing use of 'GM' limitation curves.

A conventional tanker has most of its tanks slack during the discharging of oil cargo, it is not of any great consequence; however, if an OBO has most of its holds slack during discharging (or loading) of oil cargo this will:

Cause the vessel to develop a slow rolling motion?
Cause extreme strain to the hull on the listed side if a list develops?
Have not much effect on stability as these vessels are designed for such conditions?
Likely cause a sudden or violent list due to the very large free surface in the broad beamed holds?

For cargo calculations there are two corrections to be made. Two tables are used for this purpose.

Shear and bending tables.
Pressure and vacuum tables.
List and trim correction tables.
Cargo calibration tables.

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