Ro-Ro Vessel

Ro-ro vessels — from roll-on/roll-off — are designed so that wheeled cargo, including automobiles, trucks, trailers, and rolling heavy equipment, can be driven or towed directly aboard through bow, stern, or side ramps without the need for cranes or derricks. Cargo is secured on vehicle decks using lashing equipment, and the ships carry large numbers of below-deck lanes and sometimes upper decks served by ramps or lifts. Pure car and truck carriers, also called PCC or PCTC vessels, carry several thousand vehicles in a dedicated multi-deck arrangement, while general ro-ro vessels carry a mix of wheeled and breakbulk cargo. The inherent large open deck volumes and free surface created by vehicle decks make ro-ro vessels particularly vulnerable to progressive flooding if a ramp or lower deck opening fails. SOLAS Chapter II-1 subdivision and stability requirements for ro-ro cargo ships were significantly strengthened after the losses of several vessels, and a damage stability standard applying the deterministic SOLAS approach is prescribed. Engineers must maintain watertight integrity of all vehicle deck openings, verify that indicator systems for ramps and doors are working, and ensure bilge level monitoring on the vehicle decks is operational before departure.