# NTSB SEA91LA227: North American Navion A, N91736, Chehalis, WA, September 1, 1991

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: September 1, 1991, 14:30 local (21:30 UTC)
- Place: Chehalis, WA
- Coordinates: 46.619575, -122.999908 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=46.6196&lon=-122.9999&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report May 27, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41527
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91LA227
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41527/pdf
- Page: https://openairdocs.org/ntsb/SEA91LA227

## Probable cause

TOTAL LOSS OF ENGINE POWER ON INITIAL TAKEOFF CLIMB DUE TO THE FATIGUE FRACTURE OF THE NUMBER ONE PISTON CONNECTING ROD RESULTING IN A FORCED LANDING AND IN FLIGHT COLLISION WITH TREES.

## 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, takeoff - initial climb
  - engine assembly,connecting rod - fatigue (cause)
  - engine assembly,connecting rod - fractured (cause)
- Forced landing, descent - emergency
- In flight collision with object, landing - flare/touchdown
  - object - tree(s) (contributing factor)

## Analysis

JUST AFTER RETRACTING THE GEAR ON TAKEOFF, THE PILOT HEARD A LOUD BANG IN THE ENGINE COMPARTMENT, AND EXPERIENCED A TOTAL LOSS OF ENGINE POWER.  THE PILOT, WHO WAS APPROXIMATELY 200 FFET ABOVE THE RUNWAY WHEN THE ENGINE FAILED, MADE A FORCED LANDING JUST OFF THE END OF THE RUNWAY, DURING THE FLARE THE AIRCRAFT IMPACTED NUMEROUS YOUNG CHRISTMAS TREES. LATER INVESTIGATION REVEALED THAT THE NUMBER ONE PISTON CONNECTING ROD HAD FRACTURED.

## Aircraft

- Registration: N91736 (not matched to a registry record)
- Reported make and model: NORTH AMERICAN NAVION A
- Category: Airplane
- Serial number: NAV-4-188
- Engines: CONTINENTAL E185-9 205 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Milligan, Lewis D.
- Registered owner: Milligan, Lewis D.
- Airworthiness certificate: Standard, Utility; Standard, Normal
- Last inspection: Annual, October 20, 1990, 47 hours before
- Destination: CLM, PORT ANGELES, WA
- Flight plan: VFR
- Airport: CLS, Chehalis, runway 33, 5,000 × 150 ft

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 68; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,146 total, 431 in this make and model, 968 as pilot in command, 16 in the last 90 days, 12 in the last 30 days, 7 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 25 statute miles
- Lowest ceiling: none
- Temperature: 70 °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 19910901037439A](https://openairdocs.org/incident/19910901037439A), Sep 1, 1991: Tmpson NAVIONA, Chehalis, WA, Destroyed. Engine quit on climbout. Crashed in christmas tree farm. Connecting rod broke due fatigue,caused engine destruction

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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