What happened
Approximately six minutes after takeoff, after reaching a level altitude of 3500 feet, the pilot reported experiencing an unidentified problem. A few minutes later, the pilot reported the same issue and decided to divert to a nearby airport.
Witnesses observed the aircraft reversing course several times. During the flight, the aircraft entered one spin but successfully recovered. The aircraft then began to climb but subsequently entered a second spin, resulting in a crash in a residential area. The impact damaged two houses.
The investigation
During the investigation, radar data indicated that the aircraft had completed a total of 360 degrees of left turns with several altitude excursions within a 0.45 mile radius. Two witnesses reported that the left engine had either stopped or was windmillng prior to the crash.
Investigators found no evidence of preimpact part failure; however, the aircraft sustained extensive damage from the impact and subsequent fire. Examination of the propellers revealed that one right propeller blade was bent approximately 145 degrees opposite the direction of rotation, while the other right propeller blade was relatively straight with compression deformation. Both left propeller blades were found at a low pitch setting, with one blade bent aft approximately 60 degrees and the other blade bent forward about 15 degrees.