ENGINE ICE/SLUSH INGESTION THAT RESULTED IN POWER INTERRUPTIONS AND FAILURE OF THE AIR DATA COMPUTER COUPLED WITH MOISTURE INGESTION OF THE STATIC SYSTEM. FACTORS WERE THE FAILURE OF THE MANUFACTURER TO CORRECT A PREVIOUSLY IDENTIFIED DESIGN DEFICIENCY THAT PERMITTED THE ACCUMULATION OF ENGINE INLET ICE/SLUSH, WHICH COULD NOT BE OBSERVED BY THE FLIGHT CREW, NOR PREVENTED BY ON-BOARD ENGINE ANTI-ICE EQUIPMENT, THE LACK OF A PROACTIVE STANCE BY THE FAA WHEN INVOLVED WITH AIRCRAFT CERTIFICATION UNDER BI-LATERAL AGREEMENTS, AND THE INADEQUACY OF THE FEDERAL AVIATION REGULATIONS REGARDING ENGINE INLET ICE PROTECTION.

THE FAILURE AND SUBSEQUENT SEIZURE OF THE REDUCTION GEAR BOX, AND THE FAILURE OF THE PROPELLER CONTROL UNIT AS A RESULT OF CONTAMINATED OIL SUPPLY WHICH IS SHARED WITH THE GEAR BOX.