Apr 23, 1994
Accident
Destroyed WONDERLAKE, IL
Injuries1 fatal
Phase of Flight-
ConditionsVMC
OperationFAR 091
Probable Cause
FATIGUE AND CATASTROPHIC FAILURE OF THE MAIN WING SPAR RESULTING FROM THE DESIGNER'S EXCESSIVE, UNVERIFIED ESTIMATE OF THE STRENGTH OF THE SPAR CAP MATERIAL AND THE MANUFACTURER'S FAILURE TO ATTAIN THE SPECIFIED STRENGTH DURING THE PRODUCTION PROCESS.
NTSB CHI94FA140