# NTSB ATL86LA177: Piper PA-24-250, N6639P, West Chester, OH, June 20, 1986

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 20, 1986, 14:45 local (18:45 UTC)
- Place: West Chester, OH
- Coordinates: 39.329784, -84.400489 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.3298&lon=-84.4005&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 7135
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL86LA177
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/7135/pdf
- Page: https://openairdocs.org/ntsb/ATL86LA177

## Sequence of events

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

- Loss of engine power(partial) - mech failure/malf, cruise - normal
  - engine assembly,piston - separation (cause)
  - maintenance,overhaul - poor, other maintenance personnel (cause)
- Forced landing, descent - emergency
- On ground/water collision with object, landing - roll

## Analysis

DRG FLT, THE ENG LOST POWER & THE PLT WAS UNABLE TO MAINTAIN ALT. HE MADE A FORCED LANDING ON A ROAD, BUT DRG THE LNDG ROLL, THE ACFT COLLIDED WITH A ROAD SIGN. A POST CRASH EXAM OF THE ENG REVEALED THE #6 CYLINDER HAD SEPARATED APRX 4' ABOVE THE CYLINDER FLANGE. A METALLURGICAL EXAM OF THE FRACTURE SURFACE REVEALED THERE WAS A FATIGUE CRACK PRESENT PRIORTO THE FAILURE. THE ENG WAS OVERHAULED APRX 11 FLT HRS PRIOR TO THE ACCIDENT. NO FATIGUE CRACKING WAS NOTED AT THAT TIME.

## Aircraft

- Registration: [N6639P](https://openairdocs.org/aircraft/N6639P), registered now, S/N 24-1761, built 1960 (OpenAirDocs)
- Reported make and model: PIPER PA-24-250
- Registry model: [Piper PA-24-250](https://openairdocs.org/model/piper-pa-24-250) (registry code 7102404) (OpenAirDocs)
- Registry engine: [Lycoming 0-540 series](https://openairdocs.org/engine/lycoming-0-540-series) (registry code 41532, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 24-1761
- Airframe hours: 4425
- Engines: LYCOMING O-540-A1C5 250 horsepower reciprocating
- Damage: Substantial damage
- Flight: Business, Part 91
- Operator: Robert O. Hefner
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, June 20, 1985, 177 hours before
- Departed: CMH, COLUMBUS, OH
- Destination: LUK, CINCINNATI, OH

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 54; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,924 total, 501 in this make and model, 1,793 as pilot in command, 50 in the last 90 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 5 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °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 19860620029539A](https://openairdocs.org/incident/19860620029539A), Jun 20, 1986: Piper PA24250, West Chester, OH, Substantial damage. Rough engine followed by total power loss. Struck road sign during forced landing. Cylinder had separated.

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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