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NTSB Reports is an independent research and search tool for public aviation accident and incident records. It brings NTSB aviation reports, structured fields, docket files, extracted figures, photos, videos, and update history into one searchable interface.

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August 31, 1985 · Thornhill Replica TS-1 Replica TS · N4463

Marengo, IL

Overview

Report Status
Preliminary report
Event Type
Accident
Date
August 31, 1985
Injury Outcomes
No injuries (1 uninjured)
Location
Marengo, IL
Aircraft
Thornhill Replica TS-1 Replica TS
Tail Number
N4463
Operator
Gerald Thornhill
Injuries
None
Aircraft Damage
Substantial
NTSB Number
CHI85LA364

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.

Full Narrative

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.

Flight

Event TypeAccident
Event Time14:00 CDT
Nearest Airport0nm
Runway0
Runway Length0
Runway Width0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftThornhill Replica TS-1 Replica TS
Tail NumberN4463
Aircraft CategoryAir
DamageSubstantial
OperatorGerald Thornhill
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsGnome · 9N · Reciprocating · 100
Seats1

People & Injuries

Injury SummaryNo injuries (1 uninjured)
Fatal0
Serious0
Minor0
Uninjured1
Total1
Crew 1Age 54 · Second Class

Conditions

ConditionsIMC
LightDaylight
WindCalm
Visibility10 sm
CeilingNone
Temperature / Dew Point0 C
Altimeter30.00 inHg
Weather SourcePILO

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Appendix: Source Data