# NTSB FTW91DRD03: Grumman G-164A, N9685, Bonita, LA, March 17, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: March 17, 1991, 09:30 local (15:30 UTC)
- Place: Bonita, LA
- Coordinates: 32.909229, -91.669692 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=32.9092&lon=-91.6697&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report March 31, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 23222
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW91DRD03
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/23222/pdf
- Page: https://openairdocs.org/ntsb/FTW91DRD03

## Probable cause

A POWER LOSS DUE TO A CRACKED CYLINDER.  A FACTOR WAS THE SOFT TERRAIN IN WHICH THE FORCED LANDING WAS PERFORMED.

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, cruise
  - engine assembly,cylinder - cracked (cause)
- Forced landing, descent - emergency
- Nose over, landing - roll
  - terrain condition - soft (contributing factor)

## Analysis

EN ROUTE TO AN AERIAL APPLICATION FIELD THE PILOT EXPERIENCED A LOSS OF POWER.  A FORCED LANDING WAS PERFORMED INTO AN OPEN FIELD, HOWEVER, DUE TO THE SOFT TERRAIN THE AIRPLANE NOSED OVER.  THE POWER LOSS WAS DUE TO A CRACKED CYLINDER.

## Aircraft

- Registration: [N9685](https://openairdocs.org/deregistered/N9685-1992-01-31), registration cancelled 1992-01-31, S/N 1206 (OpenAirDocs)
- Reported make and model: GRUMMAN 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)
- Category: Airplane
- Serial number: 1206
- Airframe hours: 5428
- Engines: P&W R-1340-AN1 600 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Arkla Flyers, Inc.
- Registered owner: Wilmont Flying Service, Inc.
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, April 1, 1990, 142 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 42; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; seat: center; flight hours: 10,163 total, 6,400 in this make and model, 10,000 as pilot in command, 10 in the last 90 days, 10 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 170° at 6 knots
- Visibility: 10 statute miles
- Temperature: 61 °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 19910317007249A](https://openairdocs.org/incident/19910317007249A), Mar 17, 1991: Scwzer G164A, Bonita, LA, Substantial damage. Engine failed on takeoff. Flipped over on forced landing. A cylinder had cracked.

## Other investigations on N9685 (1)

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 FTW87DRD11](https://openairdocs.org/ntsb/FTW87DRD11), Aug 18, 1987: Grumman G-164A (N9685), Bastrop, LA, minor damage, 1 fatal

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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