NTSB Identification: CHI88DEC02.
The docket is stored on NTSB microfiche number 39193.
Accident occurred Wednesday, May 25, 1988 in PONTIAC, MI
Probable Cause Approval Date: 07/09/1990
Aircraft: CHAPPEL RATSREPUS 300, registration: N889HC
Injuries: 1 Fatal.

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.

The National Transportation Safety Board determines the probable cause(s) of this accident to be:

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

Index for May1988 | Index of months