NTSB: Leak in steering gear caused flooding, loss of California tugSep 2, 2014 04:39 PM
The sinking of a tugboat near the California coast in April 2013 was the result of a steering gear leak that caused uncontrolled flooding in the engine room, federal investigators said.
No one was injured in the accident, but the 76-foot twin screw tug Delta Captain sank in deep water and has not been recovered.
On April 13, 2013, at about 1500, Delta Captain sank approximately 13 nm off the coast of Point Sur, Calif. The four crewmembers abandoned ship in a life raft and were rescued by a U.S. Coast Guard helicopter.
Delta Captain was towing the 225-foot deck barge DB 5 in 14- to 16-foot seas with gale force winds when the engineer on duty “noticed water entering the space at the upper area of the aft bulkhead of the engine room, in the vicinity of a 6-inch diameter pipe that passed through the bulkhead to the steering gear space,” the National Transportation Safety Board (NTSB) said in a recent report.
For several minutes, the crew attempted to prevent the ingress of water by starting the bilge pump and the fire pump, and by trying to plug the water’s point of entry. A final attempt was made to release the towline to the barge, but the crew could not reach the winch drum because the stern had become partially submerged.
At about 1500, the captain made a mayday call to the Coast Guard and ordered his crew to abandon ship. At 1502, the vessel’s emergency position indicating radio beacon (EPIRB) was automatically activated as the vessel sank.
A rescue helicopter arrived at 1623 and hoisted the crew to safety. The crew was flown to Monterey, Calif., where they were tested for drugs and alcohol seven hours after the accident. All test results were negative.
According to the crew, Delta Captain remained attached to the deck barge via towline for an indeterminate time after sinking. When two towing vessels commissioned by Coast Guard Sector Los Angeles arrived at the adrift barge the following day, at about 1100, the towline had snapped and Delta Captain had sunk.
The NTSB report said Delta Captain sank in about 3,000 feet of water, making salvage impossible. The total value of the boat is estimated at $2.5 million.
The NTSB does not indicate any negligence on the part of the crew.
“The probable cause of the sinking was uncontrolled flooding of the steering gear space and engine room from an undetermined source in the steering gear space,” federal investigators said.
Delta Captain is owned by Marine Express of Alameda, the vessel’s home port. The company declined to comment on the accident or on the NTSB report.