20 October 2009

Close Call When an R44 Helicopter Hits a Hanger and Crashed on 5 August 2004

In this 5 August 2004 accident (NTSB Report CHI04LA212) in Chesterfield, MO, a Robinson R44 helicopter (N7036J), with a pilot and three passengers on board, was substantially damaged when the main rotor contacted an open hangar door during takeoff and the helicopter subsequently impacted the ground. The pilot stated that the helicopter was parked on the ramp approximately 35 feet from the hangar. The hangar door was open and extended about 10 feet out over the ramp. A review of a video of the accident taken by a witness on the ground revealed that after the helicopter lifted off, it paused in a hover for a few seconds and then began to climb out, subsequently contacting the door.

The helicopter's main rotor clipped the bottom edge of the door, and then descended to the ramp. The subsequent hard landing caused the skids to collapse and the main rotor to sever the tail boom. A ground witness to the accident submitted a video recording of the accident flight. No drift toward the hangar building was observed prior to rotor blade contact with the door.

Witness Video of Accident Flight video
Source: NTSB


Probable Cause
The NTSB concluded that the crash was due to the pilot's inadequate preflight planning, his selection of an unsuitable takeoff area, and his failure to maintain clearance from the open hangar door. They also concluded that the open hangar door was a contributing factor.

Additional Information
Although the NTSB states that the helicopter was substantially damaged, FAA registry records show that the aircraft was destroyed and that the registration number (N7036J) was canceled about three months after the crash.

Related Information
NTSB Factual Report (PDF)
NTSB Probable Cause Findings (PDF)
NTSB Full Narrative

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