Study category

Cargo Operations

Container stowage, stability calculations, bunkering, crane operations, and port management — the core of the Chief Mate's daily job and the subject of the USCG Deck General cargo examination module. These games are built around real IMO CSS Code rules, actual stability calculations, and the operational decisions made before every commercial departure.

📦 Stow It Container stowage puzzle: weight, reefer slots, IMDG segregation, and port-order discharge across 6 ship classes. 📋 Cargo Plan Distribute container weights to hit the departure draft marks and meet GM requirements. ⚖️ Stability Calculator GM, free surface correction, list, loll — USCG Deck General stability module. ⛽ Bunkering MARPOL Annex I fuel transfer — flow rates, topping-up sequence, overflow prevention, SOPEP. 🏗️ Cargo Gear Ship's crane: luff and hoist to clear the hatch — SWL, lead angles, heavy-lift procedure. 🏙️ Port Tycoon Run a container terminal — berth productivity, crane cycle time, yard density, and capital reinvestment.

Cargo operations — what the Chief Mate actually does

The Chief Officer (Chief Mate) is the ship's Cargo Officer. Their primary responsibilities are planning and executing every cargo operation: container stowage planning, stability verification before departure, dangerous goods segregation compliance, cargo gear inspection, and fuel management during bunkering. These responsibilities are examined in the USCG Deck General module and assessed at the STCW Management Level under Table A-II/2.

Container ship stowage planning is both a regulatory and a commercial obligation. An incorrect stow that violates the IMO Cargo Securing Manual, creates an unstable departure condition, or misroutes cargo for discharge can result in cargo damage claims, Port State Control deficiencies, or structural damage from deck stress. These games simulate the decision pressure of real stowage planning.

Cargo operations topics covered

Container stowage (IMO CSS Code): weight classes in lower tiers, reefer slot power allocation, IMDG Code stowage categories, port-order discharge sequencing
Stability (SOLAS II-1/22): GM calculation, free surface effect, list vs. loll, Trim and Stability Booklet compliance
Bunkering (MARPOL Annex I): tank filling sequence, overflow prevention, bunker delivery note, SOPEP spill response
Cargo gear (ILO 152): Safe Working Load, lead angle reduction factors, annual certification, heavy-lift configurations
Port management: berth productivity (TEU/crane-hour), yard density, demand scheduling, terminal upgrade economics

Stow It — the most-played game on the arcade — uses real stowage rules as the difficulty curve and scales across six ship classes from a coastal feeder to a 10,000-TEU ULCV. The stability calculations in Stability Calculator are drawn directly from USCG NMC examination question types.