Trim and stability calculator

A trim and stability calculator, the onboard loading computer, is the approved software the deck officers use to plan and check each loading and ballast condition before sailing. It computes displacement, drafts, trim, GM and the GZ righting-arm curve, and the still-water shear force and bending moment, then tests them against the ship’s intact and damage-stability criteria and the approved hull-girder strength limits. SOLAS Chapter II-1 Regulation 5-1 requires the stability information, and class type-approves the instrument and its loading manual. The officer enters cargo, ballast, fuel, and tank soundings; the tool flags any condition that breaches a limit. It does not replace the approved stability booklet, which remains the legal reference.