# NTSB CHI91DCA01: Gremminger Kolb Twinstar, N7175J, St. Genevieve, MO, June 1, 1991

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Final report
- Date: June 1, 1991, 08:30 local (13:30 UTC)
- Place: St. Genevieve, MO
- Coordinates: 37.97026, -90.040748 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.9703&lon=-90.0407&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious
- Status: Completed, report December 4, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 14792
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI91DCA01
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/14792/pdf
- Page: https://openairdocs.org/ntsb/CHI91DCA01

## Probable cause

THE FAILURE OF THE PILOT TO ABORT THE TAKEOFF AND IMPROPER REMEDIAL ACTION BY THE PILOT RATED PASSENGER AFTER ASSUMING CONTROL OF THE AIRPLANE.  A FACTOR ASSOCIATED WITH THE ACCIDENT IS THE PILOT LOSING DIRECTIONAL CONTROL DURING THE TAKEOFF GROUND RUN.

## Sequence of events

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

- Loss of control - on ground/water, takeoff - roll/run
  - directional control - not maintained, pilot in command (contributing factor)
  - aborted takeoff - not performed, pilot in command (cause)
- In flight collision with object, takeoff - initial climb
  - object - vehicle
  - remedial action - improper, pilot passenger (cause)

## Analysis

THE ACCIDENT AIRPLANE COLLIDED WITH FARM EQUIPMENT DURING A GROUND RUN FOR TAKEOFF.  THE PILOT CONTINUED THE TAKEOFF AFTER LOSING DIRECTIONAL CONTROL.  A PILOT RATED PASSENGER ASSUMED CONTROL OF THE AIRPLANE JUST BEFORE IMPACT AND UNSUCCESSFULLY ATTEMPTED TO HOP THE AIRPLANE OVER THE EQUIPMENT.

## Aircraft

- Registration: [N7175J](https://openairdocs.org/deregistered/N7175J-2011-05-24), registration cancelled 2011-05-24, S/N 9043, built 1989 (OpenAirDocs)
- Reported make and model: GREMMINGER KOLB TWINSTAR (KOLB TWINS)
- Registry model: [Gremminger Greg KOLB TWINSTAR](https://openairdocs.org/model/gremminger-greg-kolb-twinstar) (registry code 056161L) (OpenAirDocs)
- Registry engine: [Bombardier ROTAX (ALL)](https://openairdocs.org/engine/bombardier-rotax-all) (registry code 09050, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 9043
- Airframe hours: 71
- Engines: ROTAX 503UL 54 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Greg W. Gremminger
- Registered owner: Greg W. Gremminger
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, August 17, 1990, 71 hours before
- Airport: H90, Ste. Genevieve, runway 13, 1,600 × 90 ft, grass/turf

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 34; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 121 total, 14 in this make and model, 75 as pilot in command, 4 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 20 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 19910601019219A](https://openairdocs.org/incident/19910601019219A), Jun 1, 1991: Amtrkb TWINSTAR, Ste Genevieve, MI, Substantial damage. Lost control taking off in gusty crosswind. Turned off runway. Continued takeoff. SIC tried avoid crash but failed.

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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