# NTSB LAX91LA183: Cessna 172N, N737GY, Grass Valley, CA, April 27, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: April 27, 1991, 11:00 local (18:00 UTC)
- Place: Grass Valley, CA
- Coordinates: 38.819084, -123.509429 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=38.8191&lon=-123.5094&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report May 7, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27180
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA183
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27180/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA183

## Probable cause

THE FAILURE OF THE PILOT TO MAINTAIN DIRECTIONAL CONTROL AND TO ADEQUATELY COMPENSATE FOR THE WIND CONDITIONS RESULTING IN AN ON GROUND LOSS OF CONTROL AND SUBSEQUENT ON GROUND COLLISION WITH A DRAINAGE DITCH.

## Sequence of events

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

- Loss of control - on ground/water, takeoff - roll/run
  - weather condition - crosswind
  - compensation for wind conditions - inadequate, pilot in command (cause)
  - directional control - not maintained, pilot in command (cause)
  - lack of total experience, pilot in command (contributing factor)
- On ground/water encounter with terrain/water, takeoff - roll/run
  - terrain condition - ditch

## Analysis

THE NEWLY CERTIFICATED PRIVATE PILOT SAID HE WAS INTO THE TAKEOFF GROUND ROLL WHEN A SUDDEN CROSS WIND GUST CAUSED THE AIRCRAFT TO WEATHER VANE. HE LOST DIRECTIONAL CONTROL, VEERED OFF THE RUNWAY AND COLLIDED WITH A DRAINAGE DITCH.

## Aircraft

- Registration: [N737GY](https://openairdocs.org/deregistered/N737GY-1991-09-20), registration cancelled 1991-09-20, S/N 17269418 (OpenAirDocs)
- Reported make and model: CESSNA 172N
- Registry model: [Cessna 172N](https://openairdocs.org/model/cessna-172n) (registry code 2072434) (OpenAirDocs)
- Category: Airplane
- Serial number: 17269418
- Engines: LYCOMING O-320 160 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Safari Air
- Last inspection: Unknown, January 2, 2000
- Destination: LVK, LIVERMORE, CA
- Airport: 017, Nevada Co, runway 25, 4,300 × 50 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 38; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; flight hours: 93 total, 62 in this make and model, 9 in the last 90 days, 5 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: variable at 10 knots, gusting 15
- Visibility: 50 statute miles
- Lowest ceiling: none

## 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 19910427012829A](https://openairdocs.org/incident/19910427012829A), Apr 27, 1991: Cessna 172N, Grass Valley, CA, Substantial damage. Reported sudden crosswind gust caused aircraft to weather vane. Lost control. Ran off runway into a ditch.

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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