NTSB Probable Cause

THE INHERENT LIMITATIONS OF THE SEE-AND-AVOID CONCEPT OF SEPARATION OF AIRCRAFT OPERATING UNDER VISUAL FLIGHT RULES THAT PRECLUDED THE PILOTS OF THE MU-2 AND THE PA-32 FROM RECOGNIZING A COLLISION HAZARD AND TAKING ACTIONS TO AVOID THE MIDAIR COLLISION. CONTRIBUTING TO THE CAUSE OF THE ACCIDENT WAS THE FAILURE OF THE MU-2 PILOT TO USE ALL THE AIR TRAFFIC CONTROL SERVICES AVAILABLE BY NOT ACTIVATING HIS INSTRUMENT FLIGHT RULES FLIGHT PLAN BEFORE TAKEOFF. ALSO CONTRIBUTING TO THE CAUSE OF THE ACCIDENT WAS THE FAILURE OF BOTH PILOTS TO FOLLOW RECOMMENDED TRAFFIC PATTERN PROCEDURES, AS RECOMMENDED IN THE AIRMAN'S INFORMATION MANUAL, FOR AIRPORT ARRIVALS AND DEPARTURES. (NTSB REPORT AAR-93/05)