# NTSB DEN84LA235: Grumman G-164A, N4593, Chamerlain, SD, July 25, 1984

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: July 24, 1984, 20:00 local (Jul 25, 1984, 01:00 UTC)
- Place: Chamerlain, SD
- Coordinates: 43.799476, -99.319572 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=43.7995&lon=-99.3196&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): 16442
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN84LA235
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/16442/pdf
- Page: https://openairdocs.org/ntsb/DEN84LA235

## 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
  - engine assembly,cylinder - failure,total (cause)
  - maintenance,installation - improper, other maintenance personnel (cause)
- Forced landing, descent - emergency
- Main gear collapsed, landing - roll
  - terrain condition - soft (contributing factor)

## Analysis

THE PILOT EXPERIENCED AN ENGINE FAILURE AND EXECUTED AN EMERGENCY LANDING ON A NARROW ROAD WHICH RESULTED IN ONE OF THE LANDING GEAR TOUCHING DOWN ON THE SOFT SHOULDER. THE LANDING GEAR FAILED AND SUBSTANTIAL DAMAGE RESULTED. EXAMINATION OF THE ENGINE REVEALED THAT THE CYLINDER SEPERATED DUE TO IMPROPERLY TORQUED STUD BOLTS WHICH ALLOWED AN OVER STRESS CONDITION TO EXIST ON A FEW STUDS THAT WERE PROPERLY TORQUED.

## Aircraft

- Registration: [N4593](https://openairdocs.org/deregistered/N4593-2013-04-30), registration cancelled 2013-04-30, S/N 1082, built 1973 (OpenAirDocs)
- Reported make and model: GRUMMAN G-164A
- Registry model: [Grumman G-164A](https://openairdocs.org/model/grumman-g-164a) (registry code 3952704) (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: 1082
- Airframe hours: 3575
- Engines: P&W 985 AN-1 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Registered owner: Glenn John Mayer
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, March 3, 1984, 37 hours before
- Departed: CHB, CHAMBERLAIN, SD

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 36; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 2,459 total, 610 in this make and model, 2,409 as pilot in command, 382 in the last 90 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 135° at 4 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 75 °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 19840724038739A](https://openairdocs.org/incident/19840724038739A), Jul 24, 1984: Scwzer G164A, Chamberlain, SD, Substantial damage. Engine vibration and oil covered the windscreen. Nosed over landing on a road. Cylinder hold down studs broke off.

## Other investigations on N4593 (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 FTW93LA169](https://openairdocs.org/ntsb/FTW93LA169), May 27, 1993: Grumman G-164A (N4593), Weiner, AR, substantial damage. Probable cause: PARTIAL POWER LOSS DUE TO IMPROPER INSTALLATION OF THE LINKAGE CONTROL BRACKET. A FACTOR WAS THE LACK OF SUITABLE TERRAIN FOR THE FORCED LANDING.
- [NTSB MIA80FKJ03](https://openairdocs.org/ntsb/MIA80FKJ03), Oct 8, 1979: Grumman G-164A (N4593), Vincent, AL, 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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.