Oct 2, 1999
Accident
Substantial INDIANAPOLIS, IN
Injuries2 minor
Phase of Flight-
ConditionsVMC
OperationFAR 091
Probable Cause
The pilot's attempted operation of the helicopter with known deficiencies, and his improper autorotation to landing. Factors were one fouled spark plug and another partially failed spark plug in the same cylinder, and the construction area.
NTSB CHI00LA002