# NTSB LAX88LA212: Fairchild Hiller FH-1100, N53EP, Lihue, HI, June 4, 1988

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 4, 1988, 12:00 local (22:00 UTC)
- Place: Lihue, HI
- Coordinates: 21.969593, -159.350799 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=21.9696&lon=-159.3508&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 5 uninjured
- Status: Completed, report October 16, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 26024
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX88LA212
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/26024/pdf
- Page: https://openairdocs.org/ntsb/LAX88LA212

## Probable cause

FATIGUE FAILURE OF THE ENGINE TO TRANSMISSION DRIVE SHAFT ENGINE COUPLING DUE TO AN ANGULAR MISALIGNMENT OF THE DRIVE SHAFT.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, cruise
  - rotor drive system,engine to transmission drive - fatigue (cause)
  - maintenance,alignment - improper (cause)
  - rotor drive system,engine to transmission drive - failure,total (cause)
  - rotor drive system,engine to transmission drive - disengaged (cause)
- Forced landing, descent - emergency
  - terrain condition - water (contributing factor)
  - autorotation - attempted, pilot in command
  - terrain condition - none suitable (contributing factor)
- Hard landing, landing - flare/touchdown

## Analysis

THE PILOT SAID THAT THE AIRCRAFT WAS IN NORMAL CRUISE FLIGHT WHEN HE NOTICED THAT THE ENGINE WAS NO LONGER DRIVING THE ROTOR SYSTEM. THE PILOT ENTERED AN AUTOROTATION AND HAD TO STRETCH THE GLIDE SLIGHTLY TO A SUITABLE LANDING AREA ON AN OFF SHORE REEF. THE HELICOPTER MADE A HARD LANDING ON THE REEF IN ABOUT ONE FOOT OF WATER. ON SITE EXAMINATION OF THE HELICOPTER BY FAA AIRWORTHINESS INSPECTORS REVEALED THAT THE BENDIX COUPLING ON THE ENGINE TO TRANSMISSION SHAFT HAD RUPTURED ON THE ENGINE END OF THE SHAFT. METALLURGICAL EXAMINATION OF THE FAILED COUPLING REVEALED A FATIGUE FRACTURE IN A CIRCUMFERENTIAL ORIENTATION ON THE COUPLING DISK. THE DRIVE SHAFT COUPLINGS ARE THE SUBJECT OF A RECURRING AD WHICH MANDATES ALIGNMENT MEASUREMENTS OF THE DRIVE SHAFT EVERY 100 HOURS. THE LAST ALIGNMENT CHECK WAS DONE ABOUT 60 HOURS PRIOR TO THE ACCIDENT.

## Aircraft

- Registration: [N53EP](https://openairdocs.org/deregistered/N53EP-1990-04-18), registration cancelled 1990-04-18, S/N 182 (OpenAirDocs)
- Reported make and model: Fairchild Hiller FH-1100
- Registry model: [Fairchild Hiller FH-1100](https://openairdocs.org/model/fairchild-hiller-fh-1100) (registry code 3376502) (OpenAirDocs)
- Category: Helicopter
- Serial number: 182
- Airframe hours: 2023
- Engines: ALLISON 250-C18C 274 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Part 91
- Registered owner: Preston S. Myers
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, May 13, 1988, 62 hours before
- Departed: LIH, LIHUE, HI
- Destination: LIH

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 40; commercial, private; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: right; flight hours: 6,032 total, 134 in this make and model, 5,846 as pilot in command, 123 in the last 90 days, 47 in the last 30 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 90° at 14 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 79 °F

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Accident 19880604071489A](https://openairdocs.org/incident/19880604071489A), Jun 4, 1988: Hiller FH1100, Lihue, HI, Substantial damage. Transmission drive shaft coupling fatigue sheared in flight. Autorotated to hard landing on a reef offshore.

From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

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