Mission Overview
The mission involved locating and marking a downed helicopter that was floating inverted offshore. A crewman was lowered by a nylon strap to attach a marker buoy to the wreckage.
Retrieval Attempt
As darkness set in, the crewman signaled to be brought back aboard. Another observer threw the nylon strap to the crewman, who was standing on the floating helicopter. The inboard end of the strap was attached to a seat belt anchor point. During the retrieval, the crewman released his hold on the strap and fell into the water.
Search and Drowning
A subsequent search activity located the crewman, who was found drowned.
Return Flight and Malfunction
The pilot reported a low fuel state to the participating U.S. Coast Guard helicopter and began returning toward Galveston. As the helicopter arrived over the beach, the pilot experienced a loss of directional control and performed an autorotation, resulting in a hard landing.
Cause of Malfunction
Investigation revealed that the nylon strap, which had been left hanging outside the helicopter, had become entangled around the tail rotor, shearing the drive shaft.