Lack of Risk Identification Causes Cargo Vessel Collision

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What happened?

On the night of October 29, 2015, at 2226 local time, the cargo vessel Ocean Freedom collided with a fleet of moored empty tank barges while entering the Port of Corpus Christi, Texas. 

Injuries and Damages

One crew member, who was working on one of the barges, suffered non-life-threatening injuries. Although no environmental damage was reported, the Ocean Freedom and the three tank barges sustained structural damage estimated at $750,000.

Monitoring Requested for Specialty Ships

The Ocean Freedom, carrying steel pipes, got underway from an offshore anchorage about 1942. As it headed inbound, the compulsory pilot noted that the ship was “a little bit to handle,” requiring “a lot of rudder” to bring it to the next course line. He informed the master and bridge team members that ships like the Ocean Freedom (ships whose wheelhouses were located at the bow rather than at the stern) were “specialty ships” not common in the Port of Corpus Christi. He asked them to let him know if he was oversteering or if they saw anything out of the ordinary about his handling of the ship.

An Erroneous Order

On the way to the assigned berth, the pilot met an outbound ship starboard to starboard in accordance to their meeting arrangement. This arrangement led to the Ocean Freedom being positioned closer to the south bank of the channel, near a moored naval ship. While trying to maneuver the stern of the Ocean Freedom away from the naval ship, the pilot accidentally ordered a hard-to-starboard rudder input, which was intended to be hard to port.

As a result, the ship’s heading changed rapidly toward the opposite side of the channel. At 2225, the master shouted orders of “Midships! Hard left! Full thruster to port!” and the ship’s propulsion was placed in emergency astern.

Realization of Impending Collision

As the Ocean Freedom moved across the approximately 800-foot-wide channel at about 9 knots directly toward a fleet of tank barges moored to the north bank, the pilot ordered the sounding of five short blasts on the ship’s whistle. Aware of the impending collision, he announced on VHF radio that there was an “emergency on the north bank.”

The crew on two tugboats tending the barges, having heard the whistle and radio calls, maneuvered clear of the Ocean Freedom. Just before 2226, the Ocean Freedom’s bow struck Kirby 28044, the outermost of the three moored tank barges, at about 8 knots’ speed. A tugboat crew member who was on board Kirby 28044 fell while trying to escape the collision, suffering a broken left rib and knee injury.

What went wrong?

The command error resulting in the course alteration toward the barges may have stemmed from the pilot’s point of reference. The forward location of the wheel-house was not typical of the cargo vessels that the pilot was more accustomed to navigating in the Port of Corpus Christi. Also, at the time the pilot issued the incorrect helm order he and the master were looking aft, in the opposite direction of the vessel’s movement (they were outside on the port bridge wing, ensuring that the Ocean Freedom cleared the moored naval ship).

Probable Cause

The NTSB determined that the probable cause of the collision of the Ocean Freedom with the moored tank barges was the pilot’s rudder order in a direction opposite of which he intended. Contributing to the accident was the failure of the bridge team to identify the risk of collision and take appropriate action.

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Source: NTSB