Incident
A helicopter was on final approach to an oil rig in the Gulf of Mexico when it lost tail rotor authority and directional control. The crew began an autorotation to the water, but the helicopter spun out of control to the right. It completed two to three revolutions before impacting the water. The right flotation gear deployed; however, the left flotation gear did not deploy because the pneumatic lines were pulled apart during the impact. Subsequently, the helicopter rolled over upon touchdown in the water.
Rescue
The crew and 10 of the 11 passengers escaped through the emergency windows. The remaining passenger remained in his seat, incapacitated from injuries, and drowned.
Investigation
An investigation revealed that the #1 hanger bearing had overheated and disintegrated at an extremely high temperature. This failure caused the tail rotor drive shaft to fail, leading to the loss of tail rotor authority and directional control.