Pilot Debrief

HUGHES HELICOPTERS INC 369 near Wrightwood, CA — 2018-02-01

Final reportGAA18CA117
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Date
2018-02-01
Location
Wrightwood, CA, USA
Aircraft
HUGHES HELICOPTERS INC 369
Registration
N618SG
Category
Helicopter
Highest injury
None
Fatalities
0
Phase of flight
Approach

Probable cause

The pilot’s high altitude, high gross weight landing with insufficient tail rotor thrust resulting in a loss of tail rotor effectiveness.

NTSB narrative

The helicopter pilot selected a landing site on a ridge above 8,000 ft mean sea level and initiated an approach. The helicopter descended below effective translational lift airspeed, and the pilot turned the nose of the helicopter to the right. The helicopter developed a rapid right yaw, and he applied full left pedal to arrest the yaw and forward cyclic to fly out of the condition, but the main rotor blades struck the ground. The helicopter came to rest on its left side, and sustained substantial damage to the fuselage, the tailboom and both rotor systems. The pilot reported that the maximum gross weight of the helicopter was 3,000 pounds, and the weight of the helicopter at the time of the accident was 2,700 pounds. According to the recommendation section of the National Transportation Safety Board pilot's aircraft accident report, the pilot reported that the accident could have been prevented if the helicopter wasn't so heavy. Additionally, he noted that he should have selected a better landing area with the landing direction into the wind. Per the Federal Aviation Administration Helicopter Flying Handbook pg. 11-20, "Loss of Tail Rotor Effectiveness [LTE]," when operating at high altitudes and high gross weights, especially while hovering, the tail rotor thrust may not be sufficient to maintain directional control, and LTE can occur. In this case, the hovering ceiling is limited by tail rotor thrust and not necessarily power available. The pilot reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

Analysis

Primary failure mode
Loss of control
First missed decision gate
Selecting a better landing area with wind direction considered.

NTSB coding

Evidence available

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

Docket documents2

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