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Aviation safety reports, made easier to study

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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NTSB Report

January 15, 1991 · Air Command 503 · UNREG

Tomahawk, WI

Overview

Report Status
Probable Cause
Event Type
Accident
Date
January 15, 1991
Injury Outcomes
1 injury (1 fatality)
Location
Tomahawk, WI
Aircraft
Air Command 503
Tail Number
UNREG
Operator
Charles R May
Injuries
Fatal
Aircraft Damage
Destroyed
NTSB Number
CHI91DEP03

THE PILOT OF AN UNREGISTERED GYRO-COPTER WAS MAKING TAKEOFFS AND LANDINGS IN CONDITIONS CONDUCIVE TO ICING. HE MADE A LANDING AND COMPLAINED OF ICE ON HIS GLASSES TO A WITNESS. WHEN NO GOGGLES COULD BE LOCATED HE STATED THAT HE WOULD MAKE ONE MORE TAKEOFF AND LANDING. ON THE DOWNWIND LEG OF THE FLIGHT THE AIRCRAFT WAS OBSERVED BY WITNESSES TO DEPART CONTROLLED FLIGHT, TUMBLE, AND IMPACT THE TERRAIN. WITNESSES STATED THAT DURING AN ATTEMPT TO REVIVE THE PILOT HE HAD AN ACCUMULATION OF ONE QUARTER INCH OF ICE OVER HIS EYES AND FACE.

NTSB Probable Cause

THE PILOT-IN-COMMAND'S ABRUPT MOVEMENT OF THE FLIGHT CONTROLS WHICH RESULTED IN LOSS OF ROTOR RPM AND EVENTUAL DEPARTURE FROM CONTROLLED FLIGHT. A FACTOR CONTRIBUTING WAS ICE ACCUMULATION ON THE PILOT'S FACE RESULTING IN PILOT INCAPACITATION (VISUAL DEFICIENTY).

Full Narrative

THE PILOT OF AN UNREGISTERED GYRO-COPTER WAS MAKING TAKEOFFS AND LANDINGS IN CONDITIONS CONDUCIVE TO ICING. HE MADE A LANDING AND COMPLAINED OF ICE ON HIS GLASSES TO A WITNESS. WHEN NO GOGGLES COULD BE LOCATED HE STATED THAT HE WOULD MAKE ONE MORE TAKEOFF AND LANDING. ON THE DOWNWIND LEG OF THE FLIGHT THE AIRCRAFT WAS OBSERVED BY WITNESSES TO DEPART CONTROLLED FLIGHT, TUMBLE, AND IMPACT THE TERRAIN. WITNESSES STATED THAT DURING AN ATTEMPT TO REVIVE THE PILOT HE HAD AN ACCUMULATION OF ONE QUARTER INCH OF ICE OVER HIS EYES AND FACE.

Flight

Event TypeAccident
Event Time15:10 CST
Nearest AirportTomahawk Regional (0nm N)
Runway27
Runway Length4000 ft
Runway Width25 ft
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftAir Command 503
Tail NumberUNREG
Aircraft CategoryGyro
DamageDestroyed
OperatorCharles R May
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsRotax · 503 · Reciprocating · 47
Seats1

People & Injuries

Injury Summary1 injury (1 fatality)
Fatal1
Serious0
Minor0
Uninjured0
Total1
Crew 1Age 55 · None

Conditions

ConditionsVMC
LightDaylight
Wind45° @ 2 kt
Visibility7 sm
CeilingOvercast 1000 ft
Temperature / Dew Point25 C / 0 C
Altimeter29.00 inHg
Weather SourceWIT

External Links

Appendix: Source Data