# NTSB FTW93LA239: Grumman-Schweizer G-164A, N7993, Garwood, TX, August 13, 1993

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 13, 1993, 11:15 local (16:15 UTC)
- Place: Garwood, TX
- Coordinates: 29.450967, -96.510833 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=29.4510&lon=-96.5108&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report August 1, 1994
- Report: Approved by Office Director
- NTSB case key (mKey): 18817
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW93LA239
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/18817/pdf
- Page: https://openairdocs.org/ntsb/FTW93LA239

## Probable cause

THE PARTIAL POWER LOSS FOR UNDETERMINED REASONS. A FACTOR WAS THE LACK OF SUITABLE TERRAIN ONTO WHICH A FORCED LANDING COULD BE EXECUTED.

## Sequence of events

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

- Loss of engine power(partial) - mech failure/malf, takeoff - initial climb
  - reason for occurrence undetermined (cause)
- Forced landing, descent - emergency
- Nose over, landing - roll
  - terrain condition - none suitable (contributing factor)

## Analysis

THE ENGINE BEGAN BACKFIRING AND RUNNING ROUGH SHORTLY AFTER TAKEOFF. THE PILOT STATED THAT HIS REMEDIAL ACTIONS DID NOT ALLEVIATE THE POWER LOSS AND HE WAS UNABLE TO SUSTAIN LEVEL FLIGHT. HE ELECTED TO EXECUTE A FORCED LANDING IN A RICE FIELD WHICH WAS THE ONLY OPTION AVAILABLE. THE AIRPLANE SUBSEQUENTLY NOSED OVER DURING THE LANDING ROLL. THE REASON FOR THE POWER LOSS WAS NOT DETERMINED AS THE OPERATOR DISPOSED OF THE ENGINE.

## Factual narrative

On August 13, 1993, at approximately 1115 central daylight time, a Grumman-Schweizer G-164A, N7993, was substantially damaged when it nosed over after encountering rough terrain during a forced landing near Garwood, Texas.  The forced landing was executed following a partial power loss after takeoff.  The airplane was on an aerial application flight and was flown by a commercial pilot.  There was no flight plan filed and visual meteorological conditions prevailed.  The pilot, the sole occupant, was not injured.

According to the pilot, the engine began backfiring and running "very rough" with an associated power loss shortly after takeoff from the private ag strip.  He stated he immediately began dumping the load and turning back toward the airstrip.  He further stated that switching the magnetos and increasing throttle did not alleviate the power loss and he was unable to sustain level flight.  He elected to execute a forced landing in a rice field, as it was the only option available.  He said the airplane touched down in a three point attitude; however, it nosed over during the landing roll.  The reason for the power loss was not determined due to the operator having disposed of the engine prior to a determination being made as to the cause.

## Aircraft

- Registration: [N7993](https://openairdocs.org/deregistered/N7993-2006-02-15), registration cancelled 2006-02-15, S/N 854, built 1971 (OpenAirDocs)
- Reported make and model: GRUMMAN-SCHWEIZER G-164A
- Registry model: [Grumman Acft ENG Cor-Schweizer G-164A](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164a) (registry code 3952801) (OpenAirDocs)
- Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 854
- Airframe hours: 8900
- Engines: P&W R-985-AN-1 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Registered owner: Anf Air Service, Inc.
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: 100 hour, July 21, 1993, 88 hours before
- Departed: NONE
- Destination: NONE

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 30; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 2,960 total, 952 in this make and model, 2,618 as pilot in command, 483 in the last 90 days, 170 in the last 30 days, 6 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 135° at 2 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 84 °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 19930813029389A](https://openairdocs.org/incident/19930813029389A), Aug 13, 1993: Scwzer G164A, Garwood, TX, Substantial damage. Engine rough backfiring and power loss after takeoff. Nosed over in rice field. Unable determine cause power loss.

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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