- Date
- May 6, 1989, 12:38 local (20:38 UTC)
- Place
- Girdwood, AK
- Injuries
- 2 minor
- Damage
- Destroyed
- Phase of flight
- Enroute
- Aircraft
- N524EHBell 412
- Weather
- Visual (VMC) · Day
- Status
- Completed · report August 2, 1990
- Report
- Approved by Office Director
- NTSB office
- Alaska Regional Office
- FAA report
- 19890506010839A
- Case key
- 5106
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
A main rotor flight control bolt (part number 20-057-6-38D) came out of its rod end bearing while in flight due to the bolt being improperly torqued during maintenance.
Sequence of events
NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.
Analysis
While IFR at 10,000 feet over mountainous terrain, the helciopter experienced violent vertical vibrations, which continued until the crash-landing about five minutes later. On board weather radar was used to guide the helicopter around the mountain tops, which were in the clouds. At about 200 feet above the ground, the helicopter caught fire, tail rotor control was lost, both engines quit, and cyclic control became unresponsive. The helicopter was destroyed by post-crash fire. About one hour of flt time earlier, the helicopter had undergone an inspection, during which the main rotor flight control system bolts had been retorqued. All but one of these bolts were found in the wreckage. However, the rod end for the missing bolt was found.
Aircraft
- Registration
- N524EH
- Reported as
- Bell 412
- Category
- Helicopter
- Serial number
- 33069
- Airframe hours
- 3,578
- Engine
- P&W PT6T-3B, 1,025 horsepower, turbo shaft
- Damage
- Destroyed
- Fire
- In-Flight
- Flight
- Part 135
- Registered owner
- Era Aviation, Inc.
- Airworthiness certificate
- Standard, Normal
- Last inspection
- Continuous airworthiness · May 4, 1989 · 1 hours before
- Departed
- VDZ · Valdez, AK
- Destination
- ANC · Anchorage, AK
- Flight plan
- IFR
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
- 45
- Certificates
- Airline transport, Commercial
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Helicopter, Airplane
- Medical
- Class 2, Valid Medical--no waivers/lim.
- Seat
- Right
- Toxicology
- Performed
- Flight hours
- 9,300 total · 1,700 in this make and model · 8,700 as pilot in command · 6 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 40° at 4 knots
- Visibility
- 60 statute miles
- Lowest ceiling
- 5,500 ft broken
- Temperature
- 46 °F
- Altimeter
- 29.00 inHg
- Observed at
- ANC, 37 nm away
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.