Pilot Debrief

ROBINSON HELICOPTER COMPANY R22 near Prescott, AZ — 2009-03-20

Final reportWPR09LA160
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Date
2009-03-20
Location
Prescott, AZ, USA
Aircraft
ROBINSON HELICOPTER COMPANY R22
Registration
N90764
Category
Helicopter
Highest injury
None
Fatalities
0
Phase of flight
Maneuvering

Probable cause

The pilot's failure to maintain adequate main rotor rpm while maneuvering at a low altitude.

NTSB narrative

The pilot was circling over a residential structure to allow his passenger to take photographs. He descended to 50 feet above ground level and slowed to about 40 to 50 knots indicated airspeed. The pilot said that near the completion of the second circle, he "felt and heard something," then observed the engine rpm and rotor rpm decaying along with the activation of the low rotor rpm horn and warning light. The pilot stated that "it may have been that what I felt and heard was a reaction to the downwind heading." The pilot lowered the collective and added power; however, due to his low operating altitude, the corrections did not have time to take effect before the helicopter impacted the terrain. The pilot reported the wind from 210 degrees at 10 knots gusting to 15 knots. The closest airport reported wind from 180 degrees at 7 knots, variable from 150 to 210 degrees. Robinson Safety Notice SN-34, "PHOTO FLIGHTS – VERY HIGH RISK," states, in part: "While maneuvering, the pilot may lose track of airspeed and wind conditions. The helicopter can rapidly lose translational lift and begin to settle." A postaccident engine run was conducted and the engine ran normally with no mechanical problems.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Pilot could have maintained higher altitude during the second pass to avoid loss of control.

NTSB coding

Evidence available

  • Photos
  • 4 docket documents
View NTSB final reportView NTSB docket

Docket documents4

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