- Date
- June 11, 1985, 12:00 local (20:00 UTC)
- Place
- Juneau, AK
- Injuries
- 1 fatal
- Damage
- Destroyed
- Phase of flight
- Maneuvering
- Aircraft
- N99676Bell UH-1B
- Weather
- Visual (VMC) · Day
- Status
- Completed
- Report
- Approved by Office Director
- FAA report
- 19850611023879A
- Case key
- 40048
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
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 engaged in a log slinging operation over mountainous, densely forested terrain the rotor craft suffered a total power loss forcing the pilot to execute an autorotative landing into high conifer trees. Disassembly of the engine revealed evidence that the spacer between the no. 5 compressor and the impeller had not been position seated during the last overhaul and that during the accident flight the spacer slipped into its proper position thus releasing the compressive torque load under which the assembly had been sufjected during buildip. The compressor assembly subsequently became uncoupled forcing the impeller forward into its magnesium housing. This action resulted in an overtemperature condition and breakup within the turbine assembly brought on by the combustion of magnesium particles.
Aircraft
- Registration
- N99676
- Reported as
- Bell UH-1B
- Category
- Helicopter
- Serial number
- 63-8513
- Airframe hours
- 5,043
- Engine
- Lycoming T53-L-11, 1,250 horsepower, turbo shaft
- Damage
- Destroyed
- Flight
- Other work use · Part 133
- Registered owner
- Temsco Helicopters, Inc.
- Airworthiness certificate
- Special, Restricted (Special)
- Last inspection
- Annual · April 17, 1985 · 62 hours before
- Departed
- JNU · Juneau, AK
- Flight plan
- Company VFR
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
- 36
- Certificate
- Commercial
- Medical
- Class 2, Valid Medical--no waivers/lim.
- Seat
- Left
- Toxicology
- Performed
- Flight hours
- 3,914 total · 2,100 in this make and model · 3,485 as pilot in command · 4 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 60° at 14 knots
- Visibility
- 14 statute miles
- Lowest ceiling
- 3,000 ft overcast
- Temperature
- 52 °F, dew point 46 °F
- Altimeter
- 29.00 inHg
- Observed at
- FNR, 13 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.