- Date
- May 9, 1985, 13:30 local (18:30 UTC)
- Place
- Calwood, MO
- Injuries
- 2 fatal
- Damage
- Destroyed
- Phase of flight
- Enroute
- Aircraft
- N951BBell 47G
- Weather
- Visual (VMC) · Day
- Status
- Completed
- Report
- Approved by Office Director
- FAA report
- 19850509016269A
- Case key
- 33834
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
N951B crashed in a wooded area during a powerline patrol flt which included photography of the powerline. According to witnesses, the helicopter was flying parallel to the powerline in a westerly direction when the accident occurred. Exam of the wreckage revealed the tail rotor gear box and hub, along with on tail rotor blade had separated in flt and was located aprx 50 yards from the main wreckage. The other tail rotor blade was located aprx 160 yards away from the main wreckage. Metallurgical exam of the broken yoke revealed a fatigue fracture which progressed from multiple origins at the root of the internal threads of the spline. The exam also showed that the internal threads were nitride treated. This was not a bell helicopter part. The PMA, under which this part was manufactured, prohibits nitride treatment of the spindle bore & threads.
Aircraft
- Registration
- N951B
- Reported as
- Bell 47G
- Category
- Helicopter
- Serial number
- 695
- Airframe hours
- 9,280
- Engine
- Franklin 6V-335-A, 200 horsepower, reciprocating
- Damage
- Destroyed
- Fire
- On-Ground
- Flight
- Aerial observation · Part 91
- Registered owner
- Dick Hill Helicopters, Inc.
- Airworthiness certificate
- Standard, Normal
- Last inspection
- 100 hour · April 15, 1985 · 48 hours before
- Departed
- COU · Columbia, MO
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 24
- Certificates
- Commercial, Flight instructor
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Valid Medical--w/ waivers/lim
- Seat
- Left
- Flight hours
- 210 total · 210 in this make and model · 155 as pilot in command · 130 in the last 90 days · 4 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 230° at 13 knots
- Visibility
- 20 statute miles
- Lowest ceiling
- None
- Temperature
- 75 °F, dew point 50 °F
- Altimeter
- 30.00 inHg
- Observed at
- COU, 21 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.