# NTSB SEA83LA063: Grumman 164B, N6674Q, Toppenish, WA, March 16, 1983

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: March 16, 1983, 13:00 local (21:00 UTC)
- Place: Toppenish, WA
- Coordinates: 46.280281, -120.250183 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=46.2803&lon=-120.2502&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 39665
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA83LA063
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/39665/pdf
- Page: https://openairdocs.org/ntsb/SEA83LA063

## Sequence of events

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

- Loss of control - on ground/water, landing - roll
  - weather condition - gusts (contributing factor)
  - compensation for wind conditions - inadequate, pilot in command (cause)
  - weather condition - tailwind (contributing factor)
  - directional control - not maintained, pilot in command (cause)
- On ground/water encounter with terrain/water, landing - roll
  - terrain condition - ditch (contributing factor)
- Nose over, landing - roll

## Analysis

THE AIRCRAFT NOSED OVER IN A DITCH DURING A LANDING ON A GRAVEL ROAD AFTER AN AERIAL APPLICATION FLIGHT. THE PILOT SAID THAT HE LOST DIRECTIONAL CONTROL DURING LANDING ROLLOUT AND ONE MAIN GEAR WENT INTO A DITCH. THE AIRCRAFT THEN NOSED OVER AND CAME TO REST INVERTED. THE PILOT REPORTED THE WINDS WERE SHIFTING DIRECTION AND CHANGING VELOCITY ALL DAY.

## Aircraft

- Registration: [N6674Q](https://openairdocs.org/deregistered/N6674Q-2012-07-20), registration cancelled 2012-07-20, S/N 196B, built 1977 (OpenAirDocs)
- Reported make and model: GRUMMAN 164B
- Registry model: [Grumman Acft ENG Cor-Schweizer G-164B](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164b) (registry code 3952802) (OpenAirDocs)
- Registry engine: [Pratt & Whitney R-985 series](https://openairdocs.org/engine/pratt-whitney-r-985-series) (registry code 52008, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 3952802
- Airframe hours: 17024
- Engines: CONTINENTAL R-975 525 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Registered owner: David R. Mahre
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, March 30, 1982, 186 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 31; commercial, flight instructor; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 5,565 total, 1,400 in this make and model, 5,350 as pilot in command, 10 in the last 90 days, 8 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 50° at 14 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 57 °F, dew point 30 °F
- Altimeter: 29.00 inHg
- Observed at: YKM, 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 19830316008079A](https://openairdocs.org/incident/19830316008079A), Mar 16, 1983: Scwzer G164B, Toppenish, WA, Substantial damage. Pilot lost directional control during landing on road. Wheels hit ditch causing it to flip inverted.

## Other investigations on N6674Q (2)

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 LAX96LA124](https://openairdocs.org/ntsb/LAX96LA124), Feb 21, 1996: Schweizer G-164B (N6674Q), Tracy, CA, substantial damage. Probable cause: overheating and failure of the engine's master rod and master rod bearing due to oil starvation. A factor relating to the accident was: the lack of suitable terrain for an emergency landing.
- [NTSB SEA83LA206](https://openairdocs.org/ntsb/SEA83LA206), Sep 28, 1983: Grumman G-164B (N6674Q), Selah, WA, 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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