- Date
- February 1, 2018, 09:45 local (17:45 UTC)
- Place
- Wrightwood, CA
- Injuries
- 3 uninjured
- Damage
- Substantial damage
- Phase of flight
- Landing
- Aircraft
- N618SGHughes Helicopters 369
- Defining event
- Landing: Loss of control in flight
- Weather
- Visual (VMC) · Day
- Status
- Completed · report August 27, 2018
- Report
- Approved by Office Director
- NTSB office
- General Aviation Accidents
- Parties
- FAA
- FAA report
- 20180201001939A
- Case key
- 96697
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
The pilot’s high altitude, high gross weight landing with insufficient tail rotor thrust resulting in a loss of tail rotor effectiveness.
Findings · 3
NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.
Sequence of events
The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.
Analysis
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.
Factual narrative
The helicopter pilot selected a landing site on a ridge above 8,000ft 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 at Altitude, 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.
Aircraft
- Registration
- N618SG
- Reported as
- Hughes Helicopters 369 (E)
- Category
- Helicopter
- Serial number
- 0014E
- Built
- 1982
- Airframe hours
- 8,250.8
- Engine
- Rolls Royce 250-C20B, 420 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- Part 135
- Operator
- Western Helicopters, Inc., doing business as Western Helicopters, Inc.
- Registered owner
- Helicopters Unlimited LLC
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Annual · January 2, 2018
- Departed
- RAL · Riverside, CA
- Destination
- Wrightwood, CA
- Flight plan
- Company VFR
- Equipment
- Handheld GPS, Satellite tracking device
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 75
- Injuries
- None
- Certificates
- Flight instructor, Airline transport, Commercial
- Airplane ratings
- Single-engine land
- Instrument ratings
- Airplane, Helicopter
- Medical
- Class 2, With waivers/limitations
- Last flight review
- April 24, 2017
- Seat
- Left
- Restraint
- 4-point
- Flight hours
- 20,000 total · 7,850 in this make and model · 19,000 as pilot in command · 29 in the last 90 days · 8 in the last 30 days · 3 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- Calm
- Visibility
- 10 statute miles
- Temperature
- 72 °F, dew point 28 °F
- Altimeter
- 30.04 inHg
- Observed at
- KCCB, 15 nm away
Docket · 2
The files NTSB released with the investigation on June 20, 2018, on NTSB’s docket system: statements, records, photos and specialists’ reports. 4.2 MB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.