- Date
- July 2, 1984, 14:45 local (21:45 UTC)
- Place
- Mt. St. Helens, WA
- Injuries
- 2 minor
- Damage
- Destroyed
- Phase of flight
- Approach
- Aircraft
- N58397Hughes 269C
- Weather
- Visual (VMC) · Day
- Status
- Completed · report March 4, 1988
- Report
- Approved by Office Director
- FAA report
- 19840702029719A
- Case key
- 39954
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
This accident occurred at the 5500 ft level on Mt. St. Helens. Density alt at the time was 7500 ft. at aprx 40-50 ft aglengine and rotor RPM began to decay rapidly. The acft landed hard on a rock ledge with one skid partially off the ledge. As rotor RPM continued to decay the rotor disc could no longer support the helicopter and it rolled 100 ft down the mountain sustaining substantial damage. Maintenance investigation revealed that all spark plugs were severly worn. When tested, four out of eight plugs fired intermittently. The left magneto also had burned points.
Aircraft
- Registration
- N58397
- Reported as
- Hughes 269C
- Category
- Helicopter
- Serial number
- 1090833
- Airframe hours
- 1,472
- Engine
- Lycoming HIO-360-D1A, 190 horsepower, reciprocating
- Damage
- Destroyed
- Flight
- Business · Part 91
- Registered owner
- Transwestern Helicopters
- Airworthiness certificate
- Standard, Utility
- Departed
- 1S4 · Scappoose, OR
- Destination
- Mt St Helens, WA
- Airport
- None
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
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--no waivers/lim.
- Seat
- Left
- Flight hours
- 653 total · 282 in this make and model · 562 as pilot in command · 101 in the last 90 days
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 300° at 5 knots
- Visibility
- 55 statute miles
- Lowest ceiling
- None
- Temperature
- 73 °F, dew point 54 °F
- Altimeter
- 30.00 inHg
- Observed at
- TDO, 25 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.
Other investigations on N58397 · 2
Matched to the same aircraft by N-number and date.