Danpar Aviation

While cruising above freezing level at 12,000 feet, the flight was cleared to descend and maintain 9,000 feet. About 1-1/2 minute later, the flight declared a mayday (emergency). Radio and radar contacts were lost and the aircraft crashed in a near vertical descent. Radar data showed that after starting a descent, the aircraft entered a left/descending maneuver. Subsequently, the left outboard wing panel and both engines separated in flight. The last transponder reply was at 2,800 feet. An exam revealed the left wing panel had separated from positive overload. No fatigue or pre-existing crack was found on any fracture area. Also, damage was found on the left engine's inboard cowling that matched damage on the vertical and right horizontal stabilizers; however, sequence of cowling separation was not verified. The separated wing panel and parts of the engine cowling were found about 3/4 mile from the main wreckage. An NTSB trajectory study indicated an inflight separation occurred at an altitude of approximately 5,600 feet as aircraft was heading southeast in a 50 to 70° dive. Elevation trim indicator was found with a full nose up indication. Both pilots were instrument rated. All eight occupants were killed.