Aerospatiale AS 355F1 N5802W accident near Pikes Peak, Colorado

Probable cause

The helicopter's encounter with an unexpected downdraft, which resulted in a hard landing.

NTSB analysis

The pilot was operating his dual turbine-engine helicopter near a mountain in an effort to film an automobile driving on a road below. The pilot stated that he had operated around this particular mountain several times a year over the past 24 years and had established a flight profile which minimized the associated risks. One sharp turn in the road near the peak required the pilot to fly outbound from the mountain and make a gentle 180-degree turn back to film the automobile. When the pilot flew outbound from the mountain the flying conditions were normal. However, after turning 180 degrees and on the inbound leg towards the mountain, the helicopter encountered a downdraft and was pushed toward the rising terrain. Helicopter performance at that altitude did not provide the pilot with a power margin great enough to arrest the descent. The pilot elected to perform a landing to the road rather than risk a turn down the rocky mountain slope. The helicopter subsequently touched down hard and rolled over, resulting in substantial damage to the fuselage.

Text from the NTSB. Open the NTSB docket for CEN10CA545 for the full record.