Incident Overview
On a lake, a Bell 206B helicopter (N84TA) with a pilot and passenger on board overheard radio transmissions concerning a Cessna 180A (N94259) that had become inverted on the water. The Cessna was equipped with floats. The stranded pilot had been sitting on the inverted floats for approximately five hours and exhibited symptoms of severe hypothermia and shock.
Rescue Attempt
The helicopter pilot positioned the aircraft in a hover adjacent to the inverted Cessna. At the time, wind conditions were 30 knots, generating waves of 3 to 4 feet in height. The helicopter passenger partially stepped into an external load basket attached to the right side of the helicopter and began assisting the stranded pilot in boarding. Shortly after, the helicopter started to roll to the right. During the roll, the main rotor blades struck the surface of the lake, causing the helicopter to impact the water and sink.
Aftermath
During the crash, the stranded pilot was struck by the helicopter's landing gear skid tube and suffered a serious chest injury. A pilot in a third aircraft, a float-equipped Beaver, observed the accident sequence and landed on the lake to rescue all participants. (The initial accident involving the Cessna 180 is referenced under identification number ANC95LA164.)