What happened
The flight departed its home airport at 05:02 for a flight to another airport to pick up employees of a marketing company. Shortly before the return trip began, a fourth passenger was added to the flight following the cancellation of their commercial flight. The accident occurred at 20:03, shortly after takeoff from the departure airport.
During the initial climb, radar data indicated that the pilot initially flew the assigned south-southwest heading before turning right to a westerly heading. An air traffic controller queried the pilot and issued a heading to intercept the VOR. Although the pilot corrected the heading, the aircraft subsequently began another right turn toward the west while continuing to climb. The aircraft then entered a left turn and transitioned into a spiraling, rapid descent. At the time of the descent, the aircraft was operating in instrument meteorological conditions. The Cessna 172 (registration not provided) impacted terrain in an open cornfield. There were 4 fatalities.
The investigation
Post-accident inspections of the engines and the airframe revealed no evidence of preexisting mechanical failure or malfunction. However, weight and balance calculations determined that the aircraft was at least 383 pounds over gross weight.