On Dec. 9, 1999, a CH-46 Sea Knight helicopter, with 18 people on board, crashed while attempting to land on the Navy tanker PECOS (T-AO 197) during a training exercise. The chopper's landing gear apparently snagged a metal safety net and the helicopter flipped over into the water and quickly sank.
An CH-46D/E Sea Knight crashes during a training exercise. Eleven Marines were rescued by special warfare crewmen on two nearby boats. But six Marines and a sailor drowned, their bodies recovered later from the sunken wreckage by an unmanned submersible vehicle.