# Accident 19911028054699A: Aerosp AS355F, Billings, MT, October 28, 1991

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: October 28, 1991, 19:15 local time
- Place: Billings, MT
- Damage: Substantial damage
- Phase of flight: Normal Cruise
- Operating rules: General operating rules (Part 91)
- Operator: RMXA
- Location: 45.8707° N, 108.4710° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=45.8707&lon=-108.4710&mi=10
- Aircraft: N101UC, a cancelled registration (https://openairdocs.org/deregistered/N101UC-2000-06-26) (OpenAirDocs)
- Registry model: Aerospatiale AS 355 F ECUREUIL (registry code 8680806, https://openairdocs.org/model/aerospatiale-as-355-f-ecureuil) (OpenAirDocs)
- Reported make and model: AEROSP AS355F
- Reported engine: ALLSN 250C20
- People aboard: 3
- Fatal injuries: 0
- Pilot flight hours: 2,826 total, 154 in this make and model, 59 in the last 90 days
- NTSB investigation: [NTSB SEA92LA029](https://openairdocs.org/ntsb/SEA92LA029) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19911028054699A

## Narrative

As the FAA filed it, in capitals; the FAA replaces private details with ^PRIVACY DATA OMITTED^.

ENGINE SERVICE DOOR OPENED IN FLIGHT. WAS SEVERED BY CONTACT WITH MAIN ROTORS. CREW UNAWARE. BULLETIN NOT COMPLIED.

## The NTSB's investigation of this event (1)

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.

- [NTSB SEA92LA029](https://openairdocs.org/ntsb/SEA92LA029), Oct 29, 1991: Aerospatiale AS355F1 (N101UC), Billings, MT, substantial damage. Probable cause: THE UNLATCHING AND SUBSEQUENT OPENING INFLIGHT OF THE LEFT-REAR ENGINE COWL DOOR. A FACTOR CONTRIBUTING TO THE ACCIDENT WAS THE FAILURE OF COMPANY MAINTENANCE PERSONNEL TO EXECUTE THE MANUFACTURER'S…

## Other reports on N101UC (5)

Matched to the same aircraft by N-number and date.

- [Accident 19970305002189A](https://openairdocs.org/incident/19970305002189A), Mar 5, 1997: Aerosp AS355F (N101UC), Washington, PA, Substantial damage. Maintenance flight, repositioned to heli pad. Applied collected pitch for takeoff, rolled onto left side. (.19) on March 5, 1997, at 1215 eastern standard…
- [Incident 19960125002789I](https://openairdocs.org/incident/19960125002789I), Jan 25, 1996: Aerosp AS355F1 (N101UC), Monongahela, PA, Minor damage. Narrative: while practicing simulated single engine landings (run on) forward portion of port skid tube (from forward crosstube forward) separated from…
- [Incident 19941220046009I](https://openairdocs.org/incident/19941220046009I), Dec 20, 1994: Aerosp AS355F1 (N101UC), Pittsburgh, PA. Heard loud bang enroute diverted to Pittsburgh. Cargo doors separated. Indicates door not secured prior to flight.
- [Incident 19910925048339I](https://openairdocs.org/incident/19910925048339I), Sep 25, 1991: Aerosp AS355F (N101UC), Billings, MT. Right engine fire warning after takeoff. Precautionary landing. Repaired broken wire at fire detector terminal.
- [Incident 19880512015299I](https://openairdocs.org/incident/19880512015299I), May 12, 1988: Aerosp AS355F (N101UC), Reidsville, NC, Minor damage. Tail rotor assembly separated at the gear box in flight. Made safe autorotation. Inadequate service inspections.

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. For accidents, the NTSB's own investigation is the fuller record.

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