# NTSB DEN88DQA03: Surline Sidewinder, N185SA, Moriarty, NM, March 12, 1988

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Final report
- Date: March 12, 1988, 12:15 local (19:15 UTC)
- Place: Moriarty, NM
- Coordinates: 35.000457, -106.040161 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.0005&lon=-106.0402&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 2 fatal
- Status: Completed, report April 25, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 17324
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN88DQA03
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/17324/pdf
- Page: https://openairdocs.org/ntsb/DEN88DQA03

## 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 - separation (cause)
  - maintenance,installation - improper, manufacturer (cause)
- Forced landing, descent - emergency
- Loss of control - in flight, descent - emergency
  - stall/spin - inadvertent, pilot in command (cause)

## Analysis

WITNESSES HEARD THE ACFT ENG SOUND INCREASE DRAMATICALLY AS THE ACFT PASSED OVER A GEN AVIATION AIRPORT.  THE ACFT WAS SEEN BY ANOTHER WITNESS AT LOW ATL, ESTIMATED TO BE ABOUT 200 FT, AS THE NOSE PITCHED UP.  THE ACFT THEN ENTERED A SPIN AND IMPACTED THE GROUND.  THE INVESTIGATION REVEALED THAT THE WOODEN PROPELLER HAD SEPARATED IN FLIGHT AND IT WAS LATER FOUND NEAR WHERE THE FIRST WITNESS HEARD THE ENG SOUND INCREASE.  EXAMINATION OF THE PROP SHOW ALL THE BOLTS THAT SECURE THE PROP TO THE CRANKSHAFT WERE SHEARED.  THE EXAMINATION FURTHER REVEALED THAT THERE WAS NO REINFORCING PLATE BETWEEN THE BOLT HEADS AND THE WOODEN PROP HUB, ONLY THE FRONT SPINNER BULKHEAD.  THE FRONT SPINNER BULKHEAD SHOWED WEAR AS DID THE BOLT HOLES IN THE PROP HUB.

## Aircraft

- Registration: [N185SA](https://openairdocs.org/deregistered/N185SA-2013-06-12), registration cancelled 2013-06-12, S/N 212478, built 1986 (OpenAirDocs)
- Reported make and model: SURLINE SIDEWINDER
- Registry model: [Surling John Terry SIDEWINDER](https://openairdocs.org/model/surling-john-terry-sidewinder) (registry code 05649AV) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 212378
- Airframe hours: 85
- Engines: LYCOMING O-320 150 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Registered owner: John Surline
- Airworthiness certificate: Special, Experimental (Special)
- Departed: RTN, RATON, NM
- Destination: TCS, TRUTH OR CONSEQ, NM

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 41; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; toxicology performed; flight hours: 235 total, 85 in this make and model, 23 in the last 90 days, 16 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 270° at 20 knots
- Lowest ceiling: none
- Temperature: 50 °F, dew point 10 °F
- Altimeter: 30.00 inHg
- Observed at: LVS, 62 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 (OpenAirDocs).

- [Accident 19880312017749A](https://openairdocs.org/incident/19880312017749A), Mar 12, 1988: Amtrsy SIDEWINDER, Moriarty, NM, Destroyed, 2 fatal. Lost the propeller en route. Stalled and spun into ground. Lack of a reinforcement plate allowed prop seperation.

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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