# NTSB CHI85LA364: Thornhill Replica TS-1, N4463, Marengo, IL, August 31, 1985

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: August 31, 1985, 14:00 local (19:00 UTC)
- Place: Marengo, IL
- Coordinates: 42.239135, -88.599342 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.2391&lon=-88.5993&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 13203
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI85LA364
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/13203/pdf
- Page: https://openairdocs.org/ntsb/CHI85LA364

## 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, climb
  - pull-up - initiated, pilot in command (contributing factor)
  - improper use of procedure, pilot in command (cause)
  - qualification, pilot in command
  - lack of experience, pilot in command
  - lack of familiarity with aircraft, pilot in command
- Nose over, landing - flare/touchdown
  - terrain condition - crop (contributing factor)
  - terrain condition - none suitable (contributing factor)

## Analysis

THIS AIRCRAFT IS POWERED BY A ROTARY ENGINE. THRUST IS VARIED BY SHORTING OUT ONE MAGNETO AND VARYING THE FIRING ORDER OF THE CYLINDERS VIA AN ELECTRICAL CAM ARRANGEMENT. THE MIXTURE CONTROL IS LIMITED TO ONLY A FEW SETTINGS. ONE OF WHICH IS LEVEL FLIGHT. FOLLOWING A LOW PASS OVER THE RUNWAY AT A THRUST SETTING OF 1/2 POWER AND A MIXTURE SETTING FOR LEVEL FLIGHT, THE PILOT PULLED UP INTO A CLIMB. THE ENGINE THEN DIED AND THE PILOT LANDED STRAIGHT AHEAD IN A HAY FIELD. THE HAY CAUGHT ON HIS UNDERCARRIAGE AND THE AIRCRAFT FLIPPED OVER ON ITS BACK. FOLLOWING THE ACCIDENT THE PILOT STATED THAT HE SHOULD HAVE ENRICHED THE FUEL MIXTURE PRIOR TO ATTEMPTING THE CLIMB.

## Aircraft

- Registration: [N4463](https://openairdocs.org/deregistered/N4463-1998-11-16), registration cancelled 1998-11-16, S/N 111118 (OpenAirDocs)
- Reported make and model: THORNHILL REPLICA TS-1 (REPLICA TS)
- Registry model: [Thornhill Gerald W TS-1](https://openairdocs.org/model/thornhill-gerald-w-ts-1) (registry code 05663CK) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 11-11-18
- Airframe hours: 2
- Engines: GNOME 9N 100 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Gerald Thornhill
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Unknown, August 21, 1985, 2 hours before
- Departed: RLA, MARENGO, IL

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 54; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 2,829 total, 1 in this make and model, 2,775 as pilot in command, 7 in the last 90 days, 1 in the last 24 hours

## Weather

- Conditions: Instrument (IMC), Day
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 81 °F
- Altimeter: 30.00 inHg

## 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 19850831042279A](https://openairdocs.org/incident/19850831042279A), Aug 31, 1985: Amtrgt TS1, Marengo, IL, Substantial damage. Pulled up after low pass and engine quit. Should have enriched mixture before maneuver. Flipped over in a field.

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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