Tanker engine problem led to $7.55m hit on loading dock

An incident in which 115,406 dwt Maltese-flag oil tanker Riverside made contact with a loading dock in the Port of Corpus Christi, Texas on March 15th 2021 resulted in $550,000 in damages to the vessel and $7m in damages to the dock, according to the report issued by the US National Transportation Safety Board (NTSB).

The NTSB determined that the probable cause of the contact was an ineffective evaluation and incorrect solution of a main engine starting issue by the vessel operator and the ship’s engineers.

The 2009-built Riverside was owned by Glory Riverside Navigation and operated by Thome Ship Management.

To change the propeller direction, the engine had to completely stop and then restart in the opposite direction. The main engine could be started from three locations: the bridge, the engine control room, and locally at the main engine.

On the date of the casualty, two pilots from Aransas-Corpus Christi Pilots boarded the Riverside in Corpus Christi to assist with manoeuvring the vessel out of the port.

While outbound in the Corpus Christi Channel, another tank vessel ahead of Riverside was also departing. The pilots of both vessels agreed the Riverside would slow down and allow the other vessel to depart the dock and proceed out of the port.

The pilot ordered a series of engine orders to slow the vessel, including stop; the Riverside began to sheer to port and a starboard rudder order was not effective. The pilot ordered dead slow ahead to increase the flow of water across the rudder, which required restarting the engine. The engine failed to restart on multiple occasions.

Without propulsion, the Riverside’s manoeuvrability remained limited, and its port bow struck the mooring dolphin and catwalk at the end of the loading dock.

The NTSB determined the probable cause of the contact was the ineffective evaluation and incorrect solution for a main engine start issue by the company and shipboard engineers, overlooking the fouling of the main engine’s no. 6 air start actuator valve within the starting air distributor. Contributing to the casualty was the presence of moisture in and lack of routine drainage of the air start system, which allowed the build-up of hardened grease within the air start actuator valve.

The NTSB said that on vessels with slow-speed diesel propulsion engines, starting and stopping main engines was a critical function for effective manoeuvrability. The NTSB said that it had investigated multiple casualties involving slow-speed engine pneumatic starting and control systems and, in particular, air actuating valves within the systems.

The Board said that vessel operators should ensure their crews were equipped with the resources and training to execute timely and thorough maintenance and repair on engines.