# NTSB DEN89LA144: Beauchesne/Wells Glasair TD, N544BM, Moriarity, NM, June 21, 1989

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 21, 1989, 17:00 local (23:00 UTC)
- Place: Moriarity, NM
- Coordinates: 34.999435, -106.039062 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=34.9994&lon=-106.0391&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report April 24, 1990
- Report: Approved by Office Director
- NTSB case key (mKey): 17727
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN89LA144
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17727/pdf
- Page: https://openairdocs.org/ntsb/DEN89LA144

## Probable cause

IMPROPER INSTALLATION OF THE PROPELLER WHICH RESULTED IN SEVERE VIBRATION AND FAILURE OF THE PROPELLER MOUNTING BOLTS, & THE SEPARATION OF THE PROPELLER FROM THE AIRCRAFT. ROUGH/UNEVEN DESERT TERRAIN CONTRIBUTED TO THE ACCIDENT.

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise - normal
  - propeller system/accessories - vibration (cause)
  - maintenance,installation - improper, other maintenance personnel (cause)
  - propeller system/accessories - overload
  - propeller system/accessories - separation
- Forced landing, descent - emergency
- In flight collision with terrain/water, landing - flare/touchdown
  - terrain condition - rough/uneven (contributing factor)

## Analysis

THE PLT RPRTD THAT DRG FLT, THE PROP BEGAN TO WOBBLE & SHOOK THE ACFT VIOLENTLY. HE TURNED THE ACFT AWAY FROM MTNS TO FIND A SUITABLE AREA FOR AN EMERGENCY LANDING. HOWEVER, AT AN ALT OF ABOUT 400' AGL, THE PROP SEPD & THE PLT WAS FORCED TO LAND ON DESERT TERRAIN. DRG THE LANDING, THE ACFT WAS SUBSTANTIALLY DAMAGED. AN INVESTIGATION REVEALED THE PROP HAD BEEN MOUNTED ON THE ENG WITH AN EXTENSION, BUT THE EXTENSION DID NOT HAVE A MEANS TO PRECISELY CENTER THE PROP. SUBSEQUENTLY, THE PROP BEGAN A SEVERE VIBRATION, THE PROP MOUNTING BOLTS FAILED & THE PROP SEPD FROM THE ACFT.

## Aircraft

- Registration: N544BM (not matched to a registry record)
- Reported make and model: BEAUCHESNE/WELLS GLASAIR TD
- Category: Airplane, amateur-built
- Serial number: 544
- Airframe hours: 64
- Engines: LYCOMING IO-360 190 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Moyle, Bennett I.
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, February 7, 1989, 12 hours before
- Departed: TCC, TUCUMCARI, NM
- Destination: ABQ, ALBUQUERQUE, NM

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 43; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 520 total, 47 in this make and model, 328 as pilot in command, 14 in the last 90 days, 12 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 100 °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 19890621016639A](https://openairdocs.org/incident/19890621016639A), Jun 21, 1989: Amtr GLASAIR, Moriarty, NM, Destroyed. Crash landed in desert after propeller assembly bolts sheared and separated. Shaft was off center,caused vibration.

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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