- Date
- June 27, 2011, 09:25 local (17:25 UTC)
- Place
- Ambler, AK
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Standing
- Aircraft
- C-GLHQHughes 500D
- Defining event
- Standing-engine(s) operating: Loss of control on ground
- Weather
- Visual (VMC) · Day
- Status
- Completed · report October 4, 2011
- Report
- Approved by Office Director
- NTSB office
- Alaska Regional Office
- Parties
- Federal Aviation Administration (Operations)
- Case key
- 80946
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 misalignment of the helicopter on the landing structure.
Findings · 2
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 landed a high skid, turbine-powered helicopter at a remote drilling site, and the three passengers disembarked. The remote landing site was constructed of 6-inch by 6-inch wooden beams, which required that the pilot land perpendicular to and on the beams with the helicopter's skids. The pilot reported that after landing he retarded the engine throttle to flight idle to begin the mandatory 2 minute engine cool down procedure. He then got out of the helicopter to check the placement of the helicopter's skids on the beams, and it subsequently tipped backwards, with the tail rotor striking terrain. A postaccident inspection revealed that while landing, the pilot inadvertently placed the helicopter's skids behind the aft wooden beam, and the helicopter tipped backwards once the pilot exited the helicopter. The pilot said there were no preimpact mechanical problems with the helicopter. The helicopter sustained substantial damage to the tail boom, tail rotor drive system, and tail rotor gearbox.
Factual narrative
The helicopter pilot landed a high skid, turbine-powered helicopter at a remote drilling site, and the three passengers disembarked. The remote landing site was constructed of 6-inch by 6-inch wooden beams, which required that the pilot land perpendicular to and on the beams with the helicopter's skids. The pilot reported that after landing he retarded the engine throttle to flight idle to begin the mandatory 2 minute engine cool down procedure. He then got out of the helicopter to check the placement of the helicopter's skids on the beams, and it subsequently tipped backwards, with the tail rotor striking terrain. In his written statement to the NTSB, the pilot wrote, in part: "While waiting, I stepped out of the helicopter to look under the helicopter to verify that my bear paws were both securely placed on the supporting timber. Within a moment of stepping out, I noticed movement and watched as the helicopter tipped backwards until it came to rest on the tail rotor and stinger." A postaccident inspection revealed that while landing, the pilot inadvertently placed the helicopter's skids behind the aft wooden beam, and the helicopter tipped backwards once the pilot exited the helicopter. The pilot said there were no preimpact mechanical problems with the helicopter. The helicopter sustained substantial damage to the tail boom, tail rotor drive system, and tail rotor gearbox.
Aircraft
- Registration
- C-GLHQ
- Reported as
- Hughes 500D
- Category
- Helicopter
- Serial number
- 200662D
- Airframe hours
- 18,753
- Engine
- Allison 250-C20B, 420 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- Part 135
- Operator
- Prism Helicopters
- Registered owner
- Prism Helicopters
- Airworthiness certificate
- Standard, Normal
- Departed
- Ambler, AK
- Destination
- Ambler, AK
- Flight plan
- Unknown
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 36
- Injuries
- None
- Certificate
- Commercial
- Instrument ratings
- Helicopter
- Medical
- Class 2, With waivers/limitations
- Last flight review
- May 2, 2011
- Seat
- Left
- Flight hours
- 4,975 total · 87 in this make and model · 4,857 as pilot in command · 88 in the last 90 days · 78 in the last 30 days · 2 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Visibility
- 30 statute miles
- Lowest ceiling
- None
Docket · 2
The files NTSB released with the investigation on August 5, 2011, on NTSB’s docket system: statements, records, photos and specialists’ reports. 497 KB in all.