# NTSB SEA91LA084: Cessna C-172N, N75646, Ellensburg, WA, April 13, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 13, 1991, 08:40 local (15:40 UTC)
- Place: Ellensburg, WA
- Coordinates: 46.969013, -120.470092 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=46.9690&lon=-120.4701&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 5, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41411
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91LA084
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41411/pdf
- Page: https://openairdocs.org/ntsb/SEA91LA084

## Probable cause

THE IMPROPER MAINTENANCE INSPECTION OF THE AIRCCRAFT.  A FACTOR RELATING TO THE ACCIDENT WAS A DITCH IN THE LADNING AREA.

## Sequence of events

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

- Loss of engine power, cruise
  - lubricating system,oil line - loose (cause)
  - maintenance,inspection - improper, company maintenance personnel (cause)
- On ground/water encounter with terrain/water, landing - roll
  - terrain condition - ditch (contributing factor)
- On ground/water encounter with terrain/water, landing - roll

## Analysis

THE ACFT ENGINE LOST OIL PRESSURE AND QUIT DURING CRUISE FLIGHT.  THE PILOT INITIATED AN EMERGENCY FORCED LANDING IN A FIELD ND THE ACFT IMPACTED AN IRRIGATION DITCH DRUING LANDING ROLL.  EXAM OF THE WRECKAGE REVEALED A LOOSE OIL LINE FITTING FROM THE OIL COOLER.

## Aircraft

- Registration: [N75646](https://openairdocs.org/deregistered/N75646-1997-11-06), registration cancelled 1997-11-06, S/N 17267871 (OpenAirDocs)
- Reported make and model: CESSNA C-172N
- Registry model: [Cessna 172N](https://openairdocs.org/model/cessna-172n) (registry code 2072434) (OpenAirDocs)
- Category: Airplane
- Serial number: 17267871
- Engines: LYCOMING O-320-H2AD 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Interwest Aviation
- Airworthiness certificate: Standard, Normal
- Departed: EPH, EPHRATA, WA
- Destination: YKM, YAKIMA, WA
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 55; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; flight hours: 132 total, 36 in this make and model, 80 as pilot in command, 21 in the last 90 days, 9 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 240° at 6 knots
- Visibility: 30 statute miles
- Lowest ceiling: none
- Temperature: 48 °F, dew point 30 °F
- Altimeter: 30.00 inHg
- Observed at: EAT, 27 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 19910413010249A](https://openairdocs.org/incident/19910413010249A), Apr 13, 1991: Cessna 172N, Ellensburg, WA, Substantial damage. Lost oil pressure and power. Struck ditch on forced landing. Loose oil line fitting caused oil loss. Loose igniters

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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