# NTSB CHI91DEP12: Schweizer G-164-A, N48635, Elkhorn, WI, August 20, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Final report
- Date: August 20, 1991, 14:10 local (19:10 UTC)
- Place: Elkhorn, WI
- Coordinates: 42.66991, -88.540283 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.6699&lon=-88.5403&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report December 14, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14845
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI91DEP12
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14845/pdf
- Page: https://openairdocs.org/ntsb/CHI91DEP12

## Probable cause

THE PILOT IN COMMAND'S FAILURE TO MAINTAIN ADEQUATE ALTITUDE.

## Sequence of events

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

- Dragged wing,rotor,pod,float or tail/skid, maneuvering - turn to reverse direction
  - terrain condition - crop
  - altitude - not maintained, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE AIRPLANE WAS INITIATING A LEFT TURN TO REVERSE DIRECTION DURING AERIAL APPLICATION WHEN THE LEFT WING CONTACTED ORN. AIRCRAFT CONTROL WAS NOT REGAINED.

## Aircraft

- Registration: [N48635](https://openairdocs.org/aircraft/N48635), registered now, S/N 1684, built 1976 (OpenAirDocs)
- Reported make and model: Schweizer G-164-A
- 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 R-985 series](https://openairdocs.org/engine/pratt-whitney-r-985-series) (registry code 52008, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 1684
- Airframe hours: 2614
- Engines: P&W R-985AN1 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Ag Aviation Services
- Registered owner: Ag Aviation Services
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, April 15, 1991, 250 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 47; airline transport, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 14,310 total, 2,500 in this make and model, 14,181 as pilot in command, 300 in the last 90 days, 150 in the last 30 days, 12 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 15 statute miles
- Lowest ceiling: none

## 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 19910820036849A](https://openairdocs.org/incident/19910820036849A), Aug 20, 1991: Scwzer G164A, Elkhorn, WI, Substantial damage. Caught a wing on tall corn during a spray run turn around causing loss of control and crash.

## Other investigations on N48635 (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 CHI92DEP04](https://openairdocs.org/ntsb/CHI92DEP04), Aug 31, 1992: Grumman 164A (N48635), Elkhorn, WI, destroyed. Probable cause: THE PILOT-IN-COMMAND'S INADEQUATE COMPENSATION FOR WIND CONDITIONS.
- [NTSB FTW82DA277](https://openairdocs.org/ntsb/FTW82DA277), Jul 12, 1982: Grumman G-164A (N48635), Justin, TX, 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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