# NTSB SEA91LA224: Cessna 172K, N6LG, Corbett, OR, August 28, 1991

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: August 28, 1991, 16:30 local (23:30 UTC)
- Place: Corbett, OR
- Coordinates: 45.509284, -122.210487 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=45.5093&lon=-122.2105&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor, 1 uninjured
- Status: Completed, report May 28, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 41524
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA91LA224
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41524/pdf
- Page: https://openairdocs.org/ntsb/SEA91LA224

## Probable cause

THE PILOT'S IMPROPER IN-FLIGHT PLANNING/DECISION, HIS DELAY IN TAKING REMEDIAL ACTION, AND HIS FAILURE TO MAINTAIN CLEARANCE FROM TREES ON RISING TERRAIN.  THE WEATHER AND TERRAIN CONDITIONS WERE RELATED FACTORS.

## Sequence of events

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

- In flight encounter with weather, maneuvering
  - terrain condition - mountainous/hilly (contributing factor)
  - weather condition - clouds (contributing factor)
  - weather condition - low ceiling (contributing factor)
  - weather condition - obscuration (contributing factor)
  - in-flight planning/decision - improper, pilot in command (cause)
  - remedial action - delayed, pilot in command (cause)
- In flight collision with object, maneuvering
  - terrain condition - rising (contributing factor)
  - object - tree(s)
  - clearance - not maintained, pilot in command (cause)

## Analysis

WHILE FOLLOWING TWO OTHER AIRCRAFT IN LOOSE FORMATION OVER MOUNTAINOUS TERRAIN, THE PILOT OBSERVED THAT THE OTHER TWO AIRCRAFT DISAPPEARED BEHIND A RAGGED CLOUD.  HE ELECTED TO MAKE A COURSE REVERSAL, BUT FOUND THAT HE HAD INADEQUATE TERRAIN CLEARANCE.  THE AIRCRAFT STRUCK TREES ON RISING TERRAIN AND CRASHED.

## Aircraft

- Registration: [N6LG](https://openairdocs.org/deregistered/N6LG-1991-12-23), registration cancelled 1991-12-23, S/N 17258465 (OpenAirDocs)
- Reported make and model: CESSNA 172K
- Registry model: [Cessna 172K](https://openairdocs.org/model/cessna-172k) (registry code 2072430) (OpenAirDocs)
- Category: Airplane
- Serial number: 17258465
- Engines: LYCOMING O-320-D2G 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Gerhard E. Doellefeld
- Registered owner: Gerhard E. Doellefeld
- Departed: 7S5, INDEPENDENCE, OR
- Destination: DLS, THE DALLES, OR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 69; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; flight hours: 1,341 total, 1,291 in this make and model, 1,278 as pilot in command, 30 in the last 90 days, 10 in the last 30 days

## Weather

- Conditions: Instrument (IMC), Day
- Wind: 70° at 4 knots
- Lowest ceiling: 300 ft
- Temperature: 61 °F, dew point 59 °F
- Observed at: CZK, 5 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 19910828037919A](https://openairdocs.org/incident/19910828037919A), Aug 28, 1991: Cessna 172K, Corbett, OR, Substantial damage. Continued into worsening weather then tried to retrace by a 180 but flew into trees on side of cloud obscured ridge

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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