THE DTSB
The DTSB determines the Probable Cause of this accident to be Pilot Error, in that the CFI allowed the student in the left seat to change the fuel tank selector in flight from right tank to left tank. The valve was found to be in a position between left and off, preventing the flowage of fuel in flight, and preventing the passage of pressurized air during post accident testing. The CFI became distracted by the surprise loss of thrust and allowed the aircraft to both turn and lose speed, whereupon the aircraft entered an aerodynamic stall and spin at an altitude such that recovery was not possible.