Loading Computer
A loading computer calculates a ship's stability, trim, and longitudinal strength for a proposed cargo condition before loading starts, and on a tanker or bulker it is the practical way to check hull stresses against class limits in the time available at the berth.
Read more — Loading Computer explained ▾
What a loading computer does
A loading computer takes the ship's hydrostatic and stability data, built from the approved ship-specific stability booklet, and runs it against a proposed distribution of cargo, ballast, and consumables. It returns draughts, trim, metacentric height (GM), and, on ships where hull strength governs, shear force and bending moment along the length of the hull, each checked against limits set in the approved loading manual. It is a calculation aid, not an autopilot: the officer still decides the loading sequence, the computer only tells them whether that sequence stays inside the ship's certified limits.
Main components
Ship-specific database
Hydrostatic tables, tank capacity plans, lightship data, and permissible stress curves entered once during type approval and locked against unauthorised editing.
Calculation engine
The software core that solves stability and longitudinal strength for a given loading condition — this is the part that carries the type approval.
Operator interface
Tank-by-tank entry screens, condition libraries for repeat voyages, and output reports formatted for port state control and the terminal.
Damage stability module
On ships where it applies — tankers, passenger ships, some bulk carriers — a parallel calculation of survivability after specified flooding cases, run against the ship's damage stability booklet.
Selection and sizing
The decisive question is not raw computing power but which stability cases the software is approved to solve for this specific ship: intact stability alone, intact plus longitudinal strength, or intact plus damage stability. Tankers and bulk carriers generally need strength and damage stability modules; smaller general cargo ships may only require intact stability. The software must be built around this ship's own hydrostatic data — a generic package with typical values is not acceptable, and class will not approve it.
Regulations and class
SOLAS Chapter XII requires loading instruments on bulk carriers to check longitudinal strength. SOLAS Chapter II-1 sets equivalent requirements for tankers and other cargo ships above defined size thresholds. Class societies issue a type approval for the software itself and a separate on-board approval confirming the installed data matches this ship's stability booklet; both need reconfirming after any major conversion, lengthening, or significant lightship change.
Typical faults
| Fault | Consequence |
|---|---|
| Outdated lightship data after conversion or repair | Draught and stability results drift from the ship's true condition. |
| Unauthorised software update without re-approval | Class approval becomes invalid, port state control can detain the ship. |
| Operator entering estimated rather than sounded tank quantities | Calculated GM and stress figures no longer reflect the actual loading condition. |
| Backup calculation method not maintained | No fallback exists if the computer fails during loading operations. |
What to look for in a supplier
- Type approval certificate naming this class society and covering the specific stability cases required for this ship type.
- Confirmation that the ship-specific data load matches the current, approved stability booklet, not an earlier revision.
- A defined process and lead time for re-approval after conversions or lightship surveys.
- Training and a manual backup calculation procedure included, not sold as an afterthought.
A loading computer approved for intact stability only is worthless for a bulk carrier loading condition that requires a strength check — verify what the approval actually covers before relying on the printout.
3 manufacturers · 3 models
CargoMax (Herbert-ABS)
1- IPC hardware failure
- Sensor data loss
- Software update issues
- Class‑approved (ABS) system with official verification each year
- Real‑time cargo weight acquisition from ship sensors
- Automated stability checks and alerts during loading/unloading
- User‑friendly graphical interface with customizable reports
- Supports multiple vessel types through modular sensor inputs
- Reported IPC hardware failures can cause downtime
- Sensor data loss incidents require redundant backups
- Software updates have occasionally caused compatibility issues
- Annual class verification adds operational overhead
- Training required for crew unfamiliar with proprietary interface
Kongsberg
1
- Tank sounding sensor failure
- Calculation error from input data
- Display unit failure
- Class‑approved software with built‑in compliance to IMO stability rules
- Real‑time integration with Kockumation tank sounding sensors for automatic draft surveys
- User‑friendly graphical interface that supports multiple cargo scenarios and ballast plans
- Ability to generate statutory reports (e.g., SOLAS, MARPOL) directly from the system
- Modular architecture allowing expansion to additional sensor inputs or remote monitoring
- System reliability is tightly linked to tank sounding sensors – failures can halt calculations
- Requires annual class survey for software validation and updates, adding operational overhead
- Limited to vessel types with conventional bulk/tank cargo configurations; less suited for Ro‑Ro or container ships
- Higher upfront cost compared with basic standalone loading calculators
- Training needed for crew to interpret advanced stability outputs correctly
NAPA
1- Software crash
- Sensor input failure
- Printer malfunction
- Draft sensor drift
- Class‑approved for SOLAS stability compliance by major classification societies
- Direct integration with draft sensors and other onboard transducers for automatic data input
- Built‑in printer produces hard‑copy loading statements on board
- User‑friendly graphical interface with customizable load plan templates
- Supported by annual software verification performed by the class society
- Software may crash if updates are not applied promptly
- Draft sensor inputs can drift, requiring regular calibration
- Onboard printer is prone to jams or ink/thermal issues in harsh marine environments
- Reliance on external sensor reliability; sensor input failure halts calculations