- Date
- August 12, 1987, 16:20 local (21:20 UTC)
- Place
- Pledger, TX
- Injuries
- 4 uninjured
- Damage
- Substantial damage
- Phase of flight
- Enroute
- Aircraft
- N33PWBell 206B
- Weather
- Visual (VMC) · Day
- Status
- Completed · report April 24, 1989
- Report
- Approved by Office Director
- FAA report
- 19870812052269A
- Case key
- 22269
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 cruising at 900' AGL, the plt noted a hvy shudder flwd by a grinding noise, loud 'bang' & a low rotor RPM signal. He made an autorotation to a road, but drg touchdown, the main rotor blades flexed dwn & severed the tail boom. An exam revealed the main pwr (short) shaft had failed due to misalignment & hi temps resulting from the misalignment. Further inv showed that the misalignment was the result of a failure of the pylon isolator mount due to debonding between the upper plate & the rubber damper element. Debonding occurred after prolonged exposure of the isolator mount to oil & grease which chemically deteriorated the bond. There was evidence the deterioration had occurred over a long period of time. The unit had been inspected periodically, but the impending failure of the bond had not been detected.
Aircraft
- Registration
- N33PW
- Reported as
- Bell 206B
- Category
- Helicopter
- Serial number
- 2223
- Airframe hours
- 4,468
- Engine
- Allison 250-C20B, 317 horsepower, turbo shaft
- Damage
- Substantial damage
- Flight
- Part 135
- Operator
- Houston Helicopters
- Registered owner
- Notlet, Inc.
- Airworthiness certificate
- Standard, Normal
- Last inspection
- AAIP · August 1, 1986 · 91 hours before
- Departed
- Bay City, TX
- Destination
- Houston, TX
- 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
- 45
- Certificates
- Airline transport, Commercial
- Airplane ratings
- Single-engine land, Multi-engine land
- Instrument ratings
- Airplane, Helicopter
- Medical
- Class 2, Valid Medical--no waivers/lim.
- Seat
- Right
- Flight hours
- 8,826 total · 1,500 in this make and model · 8,375 as pilot in command · 82 in the last 90 days · 3 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- 180° at 6 knots
- Visibility
- 10 statute miles
- Lowest ceiling
- None
- Temperature
- 97 °F, dew point 70 °F
- Altimeter
- 29.00 inHg
- Observed at
- HOU, 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.