# NTSB MKC86LA177: Grumman G-164, N634U, Goodwin, AR, August 22, 1986

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 22, 1986, 18:30 local (23:30 UTC)
- Place: Goodwin, AR
- Coordinates: 34.939373, -91.029495 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=34.9394&lon=-91.0295&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 34238
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MKC86LA177
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/34238/pdf
- Page: https://openairdocs.org/ntsb/MKC86LA177

## 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, maneuvering - aerial application
  - engine assembly - failure,total (cause)
  - engine assembly,other - failure,total (cause)
- Forced landing, descent - emergency
- Nose over, landing - flare/touchdown
  - terrain condition - none suitable (contributing factor)

## Analysis

THE AG ACFT WAS BEING USED TO SPRAY NUDRIN ON SOYBEANS WHEN THE ENGINE LOST POWER. THE PLT MADE A FORCED LANDING IN A RICE FIELD AND THE ACFT FLIPPED FORWARD TO THE INVERTED POSITION. INVESTIGATION REVEALED THE TWO-PIECE CAM REDUCTION GEAR CAME APART. AN AD HAD BEEN ISSUED IN 1966 THAT CALLED FOR REPLACEMENT WITH A ONE-PIECE GEAR AT THE NEXT ENGINE OVERHAUL AFTER 07-09-66. THIS ACCIDENT ENGINE RECEIVED ITS LAST OVERHAUL PRIOR TO THE ISSUANCE OF THAT AD.

## Aircraft

- Registration: [N634U](https://openairdocs.org/deregistered/N634U-2013-04-29), registration cancelled 2013-04-29, S/N 370, built 1965 (OpenAirDocs)
- Reported make and model: GRUMMAN G-164
- Registry model: [Grumman G-164](https://openairdocs.org/model/grumman-g-164) (registry code 3952702) (OpenAirDocs)
- Registry engine: [Jacobs R755A series](https://openairdocs.org/engine/jacobs-r755a-series) (registry code 35006, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 370
- Airframe hours: 6575
- Engines: P&W R-985 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Registered owner: Gary J. Michaelis
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, February 1, 1986

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 30; commercial; airplane ratings: single-engine land; medical: class 1, valid medical--no waivers/lim.; seat: center; flight hours: 1,308 total, 611 in this make and model, 1,234 as pilot in command, 200 in the last 90 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- 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 19860822042409A](https://openairdocs.org/incident/19860822042409A), Aug 22, 1986: Scwzer G164, Hoodwin, AR, Substantial damage. Engine failed. Nosed over on forced landing. Cam reduction gear split in half at weld. AD on this issued too late.

## Other investigations on N634U (3)

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 FTW97FA304](https://openairdocs.org/ntsb/FTW97FA304), Aug 11, 1997: Grumman G-164 (N634U), Wilmot, AR, substantial damage, 1 fatal. Probable cause: The loss of engine power due to a fractured throttle cable because the cable housing prevents an inspection of the cable by maintenance personnel. Factors were the pilot's impairment due to a heart…
- [NTSB FTW93LA101](https://openairdocs.org/ntsb/FTW93LA101), Mar 11, 1993: Grumman G-164 (N634U), Goodwin, AR, substantial damage. Probable cause: THE PILOT'S FAILURE TO COMPENSATE FOR THE CROSSWIND. A FACTOR WAS THE CROSSWIND.
- [NTSB FTW91DPG17](https://openairdocs.org/ntsb/FTW91DPG17), Jul 24, 1991: Grumman G-164 (N634U), Goodwin, AR, substantial damage. Probable cause: THE FAILURE OF THE RIGHT MAIN LANDING GEAR.

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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