What Happened
What Happened
On September 5, 2022, about 1602 local time, the 600-foot-long tanker Bow Triumph was transiting outbound on the Cooper River near Naval Weapons Station, Joint Base Charleston, South Carolina, when the vessel struck Naval Weapons Station Pier B. The vessel’s bow sustained significant damage, and a 300-foot section of the pier collapsed. No pollution or injuries were reported. Damage to the vessel and pier was estimated at $29.5 million.
What We Found
What We Found
We determined that the probable cause of the contact of the Bow Triumph with Naval Weapons Station Pier B was the pilot’s decision to maneuver the vessel close to the left bank while approaching the turn immediately before the pier, exposing the tanker to bank effect, which the pilot’s subsequent rudder and engine orders could not overcome.
What We Recommended
Planning for Hydrodynamic Forces in Areas Subject to Shoaling
Hydrodynamic forces reduce rudder effectiveness (squat and shallow water effect) and yaw the bow away from the closest bank and pull the stern in (bank effect). Shoaling can reduce the water depth in shallow waters, such as channels, below charted or expected, and therefore exacerbate the forces on a vessel. Bank effect can have an undesired effect on vessels, even for the most experienced shiphandlers. Pilots, masters, and other vessel operators should consider the risks in areas known for shoaling when planning transits.
