The National Transportation Safety Board (NTSB) continued its investigation on March 15 into the March 11, 2018, accident in which an Airbus Helicopters AS350 B2 impacted New York’s East River.
The helicopter was substantially damaged when it hit the water and subsequently rolled inverted during an autorotation, killing five passengers and injuring the pilot.
Significant activities of the investigation include:
- Interviewed Liberty Helicopters personnel, including the accident pilot;
- Conducted a teardown of the helicopter’s engine; no evidence of abnormalities was found;
- Examined structure of helicopter; no evidence of pre-impact breakup;
- Examined flight controls and found no pre-impact failure or malfunctions;
- Interviewed witnesses to crash; interviews continue;
- Obtained air traffic control voice and weather data, which is being reviewed in Washington; and
- Examined float system on helicopter, and this examination continues.
NTSB investigators are seeking videos that show different angles or aspects of the accident sequence. Broadcasters or witnesses with video are asked to contact the NTSB at witness@ntsb.gov.
From the only video I have seen,I am assuming this was a forced landing (autorotation). If so, then the pilot did not follow the flight manual procedure for a water landing.
The first mistake was to hit the water with forward speed. This will submerge the front of the floats as it plows in the water. The result is an unstable bobbing effect as the floats resurface.
The second is rolling the aircraft on it’s side. The procedure is to remain upright and pull full collective to bleed off rotor RPM. The rolling on the side is borrowed from a Bell procedure, not Airbus.