# Accident 19970725019679A: Waco YMF, Sedona, AZ, July 25, 1997

- Type: FAA accident report (Accident/Incident Data System), as reported
- Date: July 25, 1997, 19:09 local time
- Place: Sedona, AZ
- Airport: Sedona Airport
- Damage: Substantial damage
- Phase of flight: Fcd/Prec Ldg From Cruise
- Operating rules: General operating rules (Part 91)
- Location: 34.9402° N, 111.9396° W: From the FAA, an estimate near the named town, within about 3 miles
- Nearby events: https://openairdocs.org/map.md?lat=34.9402&lon=-111.9396&mi=10
- Aircraft: N369BP, registered now (https://openairdocs.org/aircraft/N369BP) (OpenAirDocs)
- Registry model: Classic WACO YMF (registry code 2240101, https://openairdocs.org/model/classic-waco-ymf) (OpenAirDocs)
- Registry engine: Jacobs R755B series (registry code 35007, https://openairdocs.org/engine/jacobs-r755b-series) (OpenAirDocs)
- Reported make and model: WACO YMF
- Reported engine: JACOBP R755B2
- People aboard: 3
- Fatal injuries: 0
- Pilot flight hours: 4,638 total, 1,539 in this make and model, 96 in the last 90 days
- NTSB investigation: [NTSB LAX97LA261](https://openairdocs.org/ntsb/LAX97LA261) (OpenAirDocs)
- FAA source: FAA Aviation Safety Information Portal (https://asip.faa.gov/)
- Page: https://openairdocs.org/incident/19970725019679A

## Narrative

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

AIRCRAFT LOST ENGINE POWER AND MADE EMERGENCY LANDING ON A HIGHWAY, HIT A SIGN, RAN INTO A DITCH. (.4)DURING A LOCAL SIGHTSEEING FLIGHT, THE ENGINE STARTED RUNNING ROUGH. THE PILOT BEGAN A TURN BACK TOWARD THE AIRPORT AND NOTICED A DECREASE IN POWER, WHICH CONTINUED TO ESCALATE. HE WAS UNABLE TO MAINTAIN ALTITUDE AND SELECTED A ROAD TO ATTEMPT A FORCED LANDING. DURING THE LANDING, THE AIRPLANE'S RIGHT WING STRUCK A TELEPHONE JUNCTION BOX. AN EXAM REVEALED THAT THE NUMBER 6 CYLINDER EXHAUST VALVE ROCKER ARM ADJUSTMENT NUT WAS LOOSE AND THE EXHAUST VALVE WAS NOT FUNCTIONING. REVIEW OF THE MAINTENANCE RECORDS DISCLOSED THAT THE VALVES WERE ADJUSTED AT THE FACTORY ABOUT 5 MONTHS AND 200 HOURS PRIOR TO THE ACCIDENT.

## 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 LAX97LA261](https://openairdocs.org/ntsb/LAX97LA261), Jul 26, 1997: Classic Waco YMF (N369BP), Sedona, AZ, substantial damage. Probable cause: A partial loss of engine power due to a loose rocker arm adjustment nut on the number 6 cylinder. The loose adjustment nut was due to inadequate maintenance adjustment performed by the engine…

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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