Incident Overview
Following unsuccessful attempts to start the engines, a mechanic removed the 'P' leads on all magnetos, making it impossible to complete the run-up checks. Shortly after gear retraction, the airplane's velocity decreased, and from about 200 feet MSL, a forced landing was made to a plowed field. Passengers reported hearing the stall warning.
Post-Incident Findings
Engine continuity was confirmed. Differential compression checks found that the left engine had four cylinders below 60 PSI, and the right engine had five cylinders below 60 PSI. Points on all magnetos were burned, and the left magneto on each engine would not fire. All spark plugs exhibited wear and deposits in the electrodes. Specifically, the bottom plugs from the left engine cylinders #3 and #5 would not fire, and the bottom plugs from the right engine cylinders #1, #3, #4, #5, and #6 would not fire. Top plugs from the right engine cylinders #5 and #6 would not fire.
Additionally, the left engine fuel control unit throttle body was not clamped at the turbocharger. The aircraft was carrying six male passengers, their baggage, and 120 gallons of fuel. Density altitude was calculated at 2,600 feet.