# NTSB CHI92DEP04: Grumman 164A, N48635, Elkhorn, WI, August 31, 1992

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Final report
- Date: August 31, 1992, 09:45 local (14:45 UTC)
- Place: Elkhorn, WI
- Coordinates: 42.669273, -88.539573 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.6693&lon=-88.5396&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report July 26, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 15245
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI92DEP04
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/15245/pdf
- Page: https://openairdocs.org/ntsb/CHI92DEP04

## Probable cause

THE PILOT-IN-COMMAND'S INADEQUATE COMPENSATION FOR WIND CONDITIONS.

## Sequence of events

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

- In flight collision with object, maneuvering - aerial application
  - weather condition - tailwind (contributing factor)
  - compensation for wind conditions - inadequate, pilot in command (cause)
  - object - tree(s)
  - proper altitude - not maintained, pilot in command (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled
  - terrain condition - ground

## Analysis

DURING AN AERIAL APPLICATION MANEUVER, THE AIRPLANE EXPERIENCED A COLLISION WITH TREES AND THE TERRAIN.  THE PILOT STATED THAT DUE TO A LOCAL DAIRY OPERATION, HE FOUND IT NECESSARY TO INITIATE THE SWATH RUN WITH A CROSSWIND TO DOWNWIND (TAILWIND) TURN TOWARD A HILLSIDE WITH TREES. THE PILOT SAID THAT HE SUSPECTED THAT THE INCREASED GROUND SPEED AND DOWNSLOPE AIRFLOW CONTRIBUTED TO THE ACCIDENT.

## Aircraft

- Registration: [N48635](https://openairdocs.org/aircraft/N48635), registered now, S/N 1684, built 1976 (OpenAirDocs)
- Reported make and model: GRUMMAN 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 R-985 series](https://openairdocs.org/engine/pratt-whitney-r-985-series) (registry code 52008, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 1684
- Airframe hours: 2709
- Engines: P&W R-985-AN1 450 horsepower reciprocating
- Damage: Destroyed
- Flight: Aerial application, Part 137
- Operator: Ag Aviation Services, Inc.
- Registered owner: Ag Aviation Services, Inc.
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, June 25, 1992, 111 hours before
- Destination: NONE

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 47; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 1,998 total, 102 in this make and model, 1,830 as pilot in command, 104 in the last 90 days, 93 in the last 30 days, 8 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 135° at 5 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 57 °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 19920831040789A](https://openairdocs.org/incident/19920831040789A), Aug 31, 1992: Scwzer G164A, Elkhorn, WI, Destroyed. Turned downwind toward hills. Encountered downdraft. Unable to outclimb rising terrain. Struck trees.

## 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 CHI91DEP12](https://openairdocs.org/ntsb/CHI91DEP12), Aug 20, 1991: Schweizer G-164-A (N48635), Elkhorn, WI, substantial damage. Probable cause: THE PILOT IN COMMAND'S FAILURE TO MAINTAIN ADEQUATE ALTITUDE.
- [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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