- Date
- June 18, 2014, 09:45 local (17:45 UTC)
- Place
- Coldfoot, AK
- Injuries
- 3 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N74713Robinson Helicopter R44 II
- Defining event
- Maneuvering-hover: Settling with power/vortex ring state
- Weather
- Visual (VMC) · Day
- Status
- Completed · report August 14, 2014
- Report
- Approved by Office Director
- NTSB office
- Alaska Regional Office
- Parties
- FAA Fairbanks FSDO
- FAA report
- 20140618011719A
- Case key
- 89480
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 failure to maintain adequate main rotor rpm while maneuvering at a low altitude, which resulted in an emergency landing on uneven terrain.
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 commercial helicopter pilot reported that the purpose of the flight was to transport two technicians to a remote site in an area of mountainous terrain. The pilot fueled the helicopter and flew approximately 30 minutes to a staging area. After loading the two passengers and their gear, he flew to the planned landing zone (LZ), in a narrow box-valley at about 2,550 feet MSL. The proposed LZ was evaluated while performing an out-of-ground-effect hover, but the pilot determined the LZ was unsuitable. A second LZ was evaluated using the same process and also found unsuitable. While hovering out of ground effect, above a third potential LZ, the helicopter began to descend and the pilot added collective pitch to stop the descent. He said the low rotor annunciator horn then sounded and the helicopter continued to descend. In an attempt to avoid landing in an area of uneven terrain, the pilot said he opted to turn the helicopter to the right and downslope, while trying to override the engine governor to attain additional engine power. The helicopter's skids subsequently struck an area of uneven, down sloping terrain. During touchdown, the helicopter nosed down, pivoted to the left, and rolled onto its left side. The helicopter sustained substantial damage to the fuselage, tail boom and main rotor drive system. The pilot reported no preaccident mechanical anomalies with the helicopter that would have precluded normal operation. The pilot characterized the down sloping wind conditions as light and variable.
Factual narrative
The commercial helicopter pilot reported that the purpose of the flight was to transport two technicians to a remote site in an area of mountainous terrain. The pilot fueled the helicopter and flew approximately 30 minutes to a staging area. After loading the two passengers and their gear, he flew to the planned landing zone (LZ), in a narrow box-valley at about 2,550 feet MSL. The proposed LZ was evaluated while performing an out-of-ground-effect hover, but the pilot determined the LZ was unsuitable. A second LZ was evaluated using the same process and also found unsuitable. While hovering out of ground effect, above a third potential LZ, the helicopter began to descend and the pilot added collective pitch to stop the descent. He said the low rotor annunciator horn then sounded and the helicopter continued to descend. In an attempt to avoid landing in an area of uneven terrain, the pilot said he opted to turn the helicopter to the right and downslope, while trying to override the engine governor to attain additional engine power. The helicopter's skids subsequently struck an area of uneven, down sloping terrain. During touchdown, the helicopter nosed down, pivoted to the left, and rolled onto its left side. The helicopter sustained substantial damage to the fuselage, tail boom and main rotor drive system. The pilot reported no preaccident mechanical anomalies with the helicopter that would have precluded normal operation. The pilot characterized the down sloping wind conditions as light and variable.
Aircraft
- Registration
- N74713
- Reported as
- Robinson Helicopter R44 II (Raven II)
- Category
- Helicopter
- Serial number
- 11220
- Built
- 2006
- Airframe hours
- 3,175
- Engine
- Lycoming IO-540 SER, 245 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Part 135
- Operator
- Quicksilver Air Inc
- Registered owner
- Quicksilver Air Inc
- Airworthiness certificate
- Standard, Normal
- Last inspection
- 100 hour · June 5, 2014
- Departed
- CXF · Coldfoot, AK
- Destination
- Coldfoot, AK
- Flight plan
- Company VFR
- Equipment
- Stall warning system
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
- 46
- Injuries
- None
- Certificates
- Flight instructor, Commercial
- Instrument ratings
- Helicopter
- Medical
- Class 2, With waivers/limitations
- Last flight review
- May 13, 2014
- Seat
- Right
- Restraint
- 3-point
- Flight hours
- 3,700 total · 2,700 in this make and model · 3,600 as pilot in command · 160 in the last 90 days · 110 in the last 30 days · 3 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 30° at 3 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- 13,000 ft overcast
- Temperature
- 57 °F, dew point 52 °F
- Altimeter
- 29.43 inHg
- Observed at
- PABT, 83 nm away
Docket · 1
The files NTSB released with the investigation on August 6, 2014, on NTSB’s docket system: statements, records, photos and specialists’ reports. 852 KB 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.