overloading may raise stresses to a point where structural cracks or even failures will occur, especially in heavy weather.
Moreover, if the limiting displacement is exceeded, the reserve of strength available to withstand the effects of damage
(c) Transverse stability. If excess cargo is carried high in the ship, safety is impaired by the rise in
center of gravity which detracts from every element of stability, namely metacentric height, righting arms, range of
stability and reserve of dynamical stability.
(2) Adverse effects on other characteristics:
(a) Speed. Increased resistance at large displacements cuts down the speed obtainable from a given
horsepower. If a given speed must be made good, substantial increases in power are sometimes necessary.
(b) Cruising radius. Increased fuel consumption for a given mileage, due to excessive displacement,
will reduce the effective cruising radius.
(c) Dryness. Overloading will reduce freeboard to the weather deck, and thus give a wetter and less
efficient ship in rough weather. The possibility of superstructure damage and damage to topside cargo from heavy water
coming on board must be considered.
Section IX. STANDARD CONDITIONS OF LOADING
5-34. CONDITIONS. In the Trim and Stability Booklet, six representative conditions of loading have been calculated to
represent the full range of the operating range of the operating drafts. Usually, these ships will operate somewhere
between the full-load departure and the beaching condition drafts.
The baseline for all calculations, drafts, and functions of form is the bottom of keel amidships. The vertical moments
of all load items have been calculated above the bottom of keel at the AP and the result corrected to the bottom of keel
The reference line for longitudinal calculations is amidships, which is Frame 64.
a. Light ship condition. This condition is the ship complete, ready for service in every respect, including liquids in
machinery at operating levels, without items of consumable or variable load.
Vertical Center of Gravity
18.3 Ft. above Keel @ AP
Longitudinal Center of Gravity
15.69 Ft. Aft of Midships