Accident Overview
The twin-engine airplane was destroyed when it impacted an earthmoving scraper and terrain in a field located approximately 2.5 miles north of the departure airport. The accident occurred during nighttime visual meteorological conditions.
Preceding Events
Witnesses reported that the pilot had aborted an earlier flight after returning to the airport and informing a mechanic of a right engine fire warning light. Maintenance personnel could not duplicate the discrepancy, and the airplane subsequently departed. Approximately 23 minutes after departure, the pilot informed air traffic control that he needed to return to the airport to have something checked out. The pilot did not specify the reason for the return to the departure airport, and during the flight back, he flew over four airports.
Flight Data and Impact
Radar track data indicated that the airplane flew over the departure end of runway 35 at an altitude of about 1,600 feet above ground level (agl) and then began a descending left turn. The airplane crossed the final approach course for runway 35 at an altitude of about 800 feet agl. Instead of landing on runway 35, the airplane continued the descending left turn and flew a course parallel to the runway, approximately 0.8 nautical miles to the right. The airplane maintained a northerly heading while continuing to descend. During the final one minute and fifty seconds of flight, the airspeed decreased from about 130 knots to about 110 knots. The last reinforced beacon return showed an altitude of about 200 feet agl and an airspeed of about 107 knots. The airplane impacted terrain about 0.75 nautical miles from the last radar contact on a magnetic heading of 338 degrees. A witness reported that the airplane was moving slowly and was "extremely low," then it disappeared, followed by an explosion and a fireball that rose approximately 1,000 feet.
Post-Impact Examination
Inspection of the wreckage revealed that the airplane struck the earthmover in a wings-level attitude. The landing gear handle was found in the "UP" position. Examination of the left engine and propeller showed damage consistent with engine operation at the time of impact. The right engine exhibited damage indicative of it not operating at impact, and the propeller was feathered. No pre-existing conditions that would have interfered with normal engine operation were found in either engine. Investigation of the right engine fire detection loop revealed surface contamination on the connector. When tested, the contaminated connector produced an intermittent signal that could generate a fire alarm indication to the pilot. After cleaning, the fire warning detection loop operated normally.