THE PILOT-IN-COMMAND'S FAILURE TO MAINTAIN AIRSPEED (VSO) WHILE MANEUVERING DURING A FORCED LANDING. THIS RESULTED IN AN INADVERTENT STALL, IN FLIGHT LOSS OF CONTROL, AND COLLISION WITH TERRAIN. CONTRIBUTING TO THE ACCIDENT WAS THE PILOT-IN-COMMAND'S FAILURE TO ENSURE THE FUEL TANK SELECTOR WAS IN THE ON POSITION. THIS RESULTED IN A TOTAL LOSS OF ENGINE POWER DURING INITIAL TAKEOFF CLIMB DUE TO FUEL STARVATION.