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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

May 25, 1988 · Chappel Ratsrepus 300 Ratsrepus · N889HC

Pontiac, MI

Overview

Report Status
Probable Cause
Event Type
Accident
Date
May 25, 1988
Injury Outcomes
1 injury (1 fatality)
Location
Pontiac, MI
Aircraft
Chappel Ratsrepus 300 Ratsrepus
Tail Number
N889HC
Operator
Harold R Chappel Ii
Injuries
Fatal
Aircraft Damage
Destroyed
NTSB Number
CHI88DEC02

THE PILOT WAS TESTING THIS EXPERIMENTAL ACROBATIC AIRCRAFT, MAKING A SECOND LOW PASS OVER THE RUNWAY WHEN A PORTION OF THE LEFT WING SEPARATED FROM THE AIRCRAFT, FOLLOWED BY LOSS OF THE LEFT AILERON, 1 1/2 ROLLS TO THE LEFT AND GROUND IMPACT. THE AIRFRAME TOTAL TIME WAS 4 HOURS. ON-SCENE INSPECTION REVEALED NO MASS BALANCE IN THE AILERONS. WITNESSES ESTIMATE SPEEDS AT OR ABOVE 150 MPH. A DESIGNATED ENGINEERING REPRESENTATIVE IN THE AREA OF FLUTTER AND VIBRATION STATED HE HAD RECOMMENDED THAT THE AIRSPEED BE LIMITED TO A MAXIMUM SPEED OF APPROXIMATELY 135 MPH UNTIL GROUND VIBRATION TESTS WERE CONDUCTED.

NTSB Probable Cause

DESTRUCTIVE WING/AILERON FLUTTER IS SUSPECTED, BUT NOT SUFFICIENTLY SUBSTANTIATED THROUGH RESEARCH AND CALCULATIONS TO BE CITED AS THE PROBABLE CAUSE OF THIS ACCIDENT.

Full Narrative

THE PILOT WAS TESTING THIS EXPERIMENTAL ACROBATIC AIRCRAFT, MAKING A SECOND LOW PASS OVER THE RUNWAY WHEN A PORTION OF THE LEFT WING SEPARATED FROM THE AIRCRAFT, FOLLOWED BY LOSS OF THE LEFT AILERON, 1 1/2 ROLLS TO THE LEFT AND GROUND IMPACT. THE AIRFRAME TOTAL TIME WAS 4 HOURS. ON-SCENE INSPECTION REVEALED NO MASS BALANCE IN THE AILERONS. WITNESSES ESTIMATE SPEEDS AT OR ABOVE 150 MPH. A DESIGNATED ENGINEERING REPRESENTATIVE IN THE AREA OF FLUTTER AND VIBRATION STATED HE HAD RECOMMENDED THAT THE AIRSPEED BE LIMITED TO A MAXIMUM SPEED OF APPROXIMATELY 135 MPH UNTIL GROUND VIBRATION TESTS WERE CONDUCTED.

Flight

Event TypeAccident
Event Time15:07 EDT
Nearest AirportOakland/Pontiac (0nm N)
Runway9L
Runway Length3251 ft
Runway Width75 ft
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftChappel Ratsrepus 300 Ratsrepus
Tail NumberN889HC
Aircraft CategoryAir
DamageDestroyed
OperatorHarold R Chappel Ii
Operating RulePart 91
Engines1
Engine TypeReciprocating
Engine DetailsLycoming · IO-540-K1A5 · Reciprocating · 300
Seats1

People & Injuries

Injury Summary1 injury (1 fatality)
Fatal1
Serious0
Minor0
Uninjured0
Total1
Crew 1Age 48 · Second Class

Conditions

ConditionsVMC
LightDaylight
Wind360° @ 15 kt
Visibility15 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter29.00 inHg
Weather SourceWFAC

Appendix: Source Data