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 TM 55-1915-200-SDC
It is not always necessary to eliminate the list entirely. In some cases, total elimination of list may be possible only
by resorting to filling of tanks on the high side. The consequent increase in displacement would probably offset any
advantage to be gained from bringing the ship upright. If the ship is manageable, any additional list correction should be
undertaken only after due thought has been given to the problem.
5-32. MINIMUM ACCEPTABLE STABILITY. In order to resist the effects of damage, it is essential that the vertical
height of the ship's center of gravity (KG) be kept below a certain value. Calculations indicate that this value is reached
when carrying 2000 tons of cargo. Therefore, the amount of cargo at departure should not exceed this total.
5-33. LIMITING DRAFT.
a. Limiting value assigned. A limiting draft of 11.5 feet above the bottom of keel amidships and 13 feet above the
bottom of keel at the aft perpendicular (4050 tons of displacement) has been assigned to these ships. Distinctive marks
have been authorized to be painted on both sides of the ship, representing the above drafts as guides against
overloading.
b. Basis of assignment. The factors responsible for the assignment of the above limits on drafts and displacement
are as follows:
(1) Reserve buoyancy.
(2) Structural strength.
CAUTION
Operating at displacements over the limiting value is detrimental to the safety and performance
of the ship in several ways which are briefly summarized below:
c. Dangers of overloading:
(1) Adverse effects on the survival power and safety of the ship:
(a) Reserve buoyancy and floodable length. If the drafts before damage exceed the limiting values, one
compartment flooding would probably result in flooding water coming over the main deck aft.
(b) Structural strength. Longitudinal strength is ample for all approved conditions of loading and is not a
factor in beaching. Uniform loading of cargo, diesel oil and ballast throughout the length of the ship will result in
decreased bending moments and stresses in the hull and decks. The longitudinal bending moment varies as the
displacement for a given local distribution and therefore hull stresses will increase in the same ratio. Extreme
5-15
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