# Incident 19790906034589I: Hnlypg HP137MK1, Denver, CO, September 6, 1979

- Type: FAA incident report (Accident/Incident Data System), as reported
- Date: September 6, 1979, 12:05 local time
- Place: Denver, CO
- Airport: Stapleton International
- Phase of flight: Descent
- Operating rules: Air taxi and commuter (Part 135)
- Location: 39.7392° N, 104.9847° W: Placed by OpenAirDocs: center of Denver, CO, within about 7 miles (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=39.7392&lon=-104.9847&mi=10
- Aircraft: N12221, a cancelled registration (https://openairdocs.org/deregistered/N12221-1992-09-02) (OpenAirDocs)
- Registry model: Handley Page HP-137 MK1 (registry code 4130402, https://openairdocs.org/model/handley-page-hp-137-mk1) (OpenAirDocs)
- Reported make and model: HNLYPG HP137MK1
- People aboard: 13
- Fatal injuries: 0
- Pilot flight hours: 4,000 total, 1,500 in this make and model, 0 in the last 90 days
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19790906034589I

## Narrative

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

GEAR AND FLAPS EXTENDED MANUALLY AFTER HYDRAULIC FAILURE.  HYDRAULIC LINES HAD RUBBED TOGETHER UNTIL FAILURE.

## Other reports on N12221 (4)

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

- [Incident 19811209085429I](https://openairdocs.org/incident/19811209085429I), Dec 9, 1981: Hnlypg HP137MK1 (N12221), Sheridan, WY, Minor damage. Pilot aborted takeoff after aircraft struck a deer on takeoff roll.
- [Incident 19810127009819I](https://openairdocs.org/incident/19810127009819I), Jan 27, 1981: Hnlypg HP137MK1 (N12221), Sheridan, WY, Minor damage. Number two engine shutdown after takeoff. Fuel/hydraulic shutoff had vibrated to off position. Saftied handle open.
- [Incident 19800309024269I](https://openairdocs.org/incident/19800309024269I), Mar 9, 1980: Bag HP137MK1 (N12221), Sheridan, WY, Substantial damage. Fast taxi to test brake installation. Hit standing water. One engine falmed out. Airplane off runway in deep mud
- [Incident 19791207048099I](https://openairdocs.org/incident/19791207048099I), Dec 7, 1979: Hnlypg HP137MK1 (N12221), Laramie, WY. Sump light lit followed by engine failure. Front compressor bearing failed.

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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