- Date
- August 13, 1990, 17:58 local (Aug 14, 1990, 00:58 UTC)
- Place
- Bieber, CA
- Injuries
- 1 serious
- Damage
- Substantial damage
- Phase of flight
- Approach
- Aircraft
- N64789Bell UH-1B
- Weather
- Visual (VMC) · Day
- Status
- Completed · report December 8, 1992
- Report
- Approved by Office Director
- Case key
- 26591
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 aircraft control when intentionally slowing his aircraft to off load water on fire. Contributing to the accident was the pilot's failure to arm and release the external load.
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
The pilot was flying a fire fighting mission and was approaching southerly ascending terrain from the east. The aircraft approached the terrain and slowed to make a water drop. As it slowed the tail turned to the left and the helicopter lost altitude and settled into the trees. The pilot heard the low RPM audio and saw the low RPM warning light. He attempted to release the water load. Examination of the engine and engine components revealed no evidence of a malfunction or failure. The temperature reportedly was between 82 to 86 degrees f with the wind from the north at 5 to 8 knots.
Aircraft
- Registration
- N64789
- Reported as
- Bell UH-1B
- Category
- Helicopter
- Serial number
- 62-4598
- Airframe hours
- 5,220
- Engine
- Lycoming T53-L11, 1,100 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- Public aircraft · Part 133
- Operator
- Intermountain Air Services
- Registered owner
- Carson Leasing & Equity Inc.
- Airworthiness certificate
- Special, Restricted (Special)
- Last inspection
- Annual · December 15, 1989 · 46 hours before
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
- 50
- Certificate
- Commercial
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Right
- Flight hours
- 20,000 total
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 270° at 8 knots
- Visibility
- 6 statute miles
- Lowest ceiling
- None
- Temperature
- 86 °F, dew point 43 °F
- Altimeter
- 29.00 inHg
- Observed at
- RBL, 92 nm away
Other investigations on N64789 · 1
Matched to the same aircraft by N-number and date.