# NTSB SEA91FA076: Piper PA-24-250, N6044P, Chehalis, WA, March 28, 1991

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: March 28, 1991, 07:40 local (15:40 UTC)
- Place: Chehalis, WA
- Coordinates: 46.620117, -122.99932 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=46.6201&lon=-122.9993&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal, 1 serious
- Status: Completed, report July 13, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41312
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91FA076
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41312/pdf
- Page: https://openairdocs.org/ntsb/SEA91FA076

## Probable cause

A LOSS OF ENGINE POWER DUE TO AN IMPROPER OVERHAUL.

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, cruise - normal
  - engine assembly,other - fatigue (contributing factor)
  - accessory drive assy,drive gear - failure,total (cause)
  - maintenance,overhaul - improper, other maintenance personnel (cause)
  - maintenance,service bulletin/letter - not followed, other maintenance personnel (contributing factor)
- Forced landing, descent - emergency
- In flight collision with object, descent - emergency
  - object - building(nonresidential)

## Analysis

DURING A CROSS COUNTRY FLT, THE ENG LOST PWR. DURING THE EMERGENCY DESCENT, THE AIRPLANE COLLIDED WITH A BUILDING. THE POST CRASH ENG INSPECTION REVEALED THAT THE CRANKSHAFT GEAR WAS NOT SEATED PROPERLY DURING THE MAJOR OVERHAUL, WHICH RESULTED IN THE FATIGUE FAILURE OF THE CRANKSHAFT DOWEL. FURTHER RESEARCH REVEALED THAT DURING THE ENG OVERHAUL, A SERVICE BULLETIN WAS NOT COMPLIED WITH TO INSTALL A CRANKSHAFT GEAR THAT WAS MANUFACTURED WITH THREE, THREE QUARTOR INCH RADIUS SCALLOPS. THESE SCALLOPS ALLOW FOR INSPECTION OF THE GEAR AND CRANKSHAFT ASSEMBLY.

## Aircraft

- Registration: [N6044P](https://openairdocs.org/deregistered/N6044P-1994-08-03), registration cancelled 1994-08-03, S/N 241140 (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)
- Category: Airplane
- Serial number: 24-1140
- Airframe hours: 3651
- Engines: LYCOMING O-540-A1C5 250 horsepower reciprocating
- Damage: Destroyed
- Flight: Business, Part 91
- Operator: Nichols Brothers Boatbuilders
- Registered owner: Nichols Brothers Boatbuilders
- Last inspection: 100 hour, March 14, 1990, 83 hours before
- Departed: PAE, EVERETT, WA
- Destination: 59S, VANCOUVER, WA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 39; commercial; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; flight hours: 667 total, 18 in this make and model, 537 as pilot in command, 18 in the last 90 days, 18 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 210° at 4 knots
- Visibility: 10 statute miles
- Lowest ceiling: 1,500 ft overcast
- Temperature: 43 °F, dew point 43 °F
- Altimeter: 30.00 inHg
- Observed at: TDO, 14 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 19910328007789A](https://openairdocs.org/incident/19910328007789A), Mar 28, 1991: Piper PA24250, Chehalils, WA, Destroyed, 1 fatal. Lost power. Landing collided with building. Improper overhaul. Crankshaft not seated. Service bulletin not complied

## Other investigations on N6044P (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 CHI72FLQ48](https://openairdocs.org/ntsb/CHI72FLQ48), Jun 8, 1972: Piper PA-24 (N6044P), Winchester, KY, substantial damage

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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