# NTSB FTW91DPJ03: Grimm Cavalier SA102.5, N413P, Mcalester, OK, July 25, 1991

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Final report
- Date: July 25, 1991, 12:00 local (17:00 UTC)
- Place: Mcalester, OK
- Coordinates: 34.92073, -95.759391 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=34.9207&lon=-95.7594&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 2 fatal
- Status: Completed, report April 8, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 23212
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW91DPJ03
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/23212/pdf
- Page: https://openairdocs.org/ntsb/FTW91DPJ03

## Probable cause

THE PILOT'S ATTEMPTED FLIGHT INTO IMC AND HIS SUBSEQUENT LOSS OF CONTROL DUE TO SPATIAL DISORIENTATION.

## Sequence of events

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

- In flight encounter with weather, cruise
  - weather condition - low ceiling (contributing factor)
  - weather condition - fog
  - weather condition - rain (contributing factor)
  - flight into known adverse weather - attempted, pilot in command (cause)
  - lack of total instrument time, pilot in command (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled
  - aircraft control - not maintained, pilot in command (cause)
  - spatial disorientation, pilot in command (cause)

## Analysis

DURING A DAYLIGHT FLIGHT FROM ENNIS, OKLAHOMA, TO OSHKOSH, WISCONSIN, THE NON-INSTRUMENT RATED PILOT TRANSITIONED FROM VFR TO IFR FLIGHT. THE PRIVATE PILOT WAS FULLY AWARE OF THE FORECASTED INSTRUMENT CONDITIONS AND EXPRESSED HIS CONCERN AS TO THE WEATHER. HE DISCUSSED THE WEATHER WITH OTHER PILOTS, AND THEY RECOMMENDED THAT HE NOT PROCEED WITH THE FLIGHT UNTIL THE WEATHER FRONT HAD PASSED. THE AIRPLANE IMPACTED THE GROUND IN A LEVEL ATTITUDE WITH NO FORWARD MOVEMENT AND WITH EVIDENCE OF SOME ROTATION.

## Aircraft

- Registration: [N413P](https://openairdocs.org/deregistered/N413P-1992-01-14), registration cancelled 1992-01-14, S/N SA102572215 (OpenAirDocs)
- Reported make and model: GRIMM CAVALIER SA102.5 (CAVALIER S)
- Registry model: [Grimm CAVALIER SA 102.5](https://openairdocs.org/model/grimm-cavalier-sa-102-5) (registry code 05613A2) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: SA1025-72215
- Airframe hours: 2301
- Engines: LYCOMING O-290-D 125 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Grimm, Larry W.
- Registered owner: Grimm, Larry W.
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Unknown, June 10, 1991, 79 hours before
- Departed: F41, ENNIS, TX
- Destination: OSH, OSHKOSH, WI
- Airport: MLC, Mcalester

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 46; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; toxicology performed; flight hours: 553 total

## Weather

- Conditions: Instrument (IMC), Day
- Wind: 150° at 8 knots
- Visibility: 6 statute miles
- Lowest ceiling: 900 ft broken
- Temperature: 75 °F, dew point 72 °F
- Altimeter: 30.00 inHg
- Observed at: MLC, 11 nm away

## 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 19910725029849A](https://openairdocs.org/incident/19910725029849A), Jul 25, 1991: Star CAVALIER, Mcalester, OK, Destroyed, 2 fatal. Crashed into trees en route. VFR pilot IFR weather. Low ceiling, rain, and fog.

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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