Pilatus PC-12, Bellefonte, Pa., March 26, 2005–The NTSB determined the probable cause of the crash of the PC-12 on an ILS approach to University Park Airport, State College, Pa., was the pilot’s failure to maintain sufficient airspeed to avoid a stall, which resulted in an inadvertent stall and spin. Factors also included the pilot’s failure to follow procedures/directives and clouds. All six people on board were killed and the airplane was destroyed.
The airplane was on an IFR flight plan from Naples, Fla. Radar data showed that the 1,900-hour private pilot had difficulty maintaining altitude and airspeed on final and wavered above and below the glide-slope, with large variations in airspeed. The airplane spun in, nose down, about three miles from the approach end of the runway. Icing conditions existed in clouds near the airport but first responders to the accident reported no ice on the airplane.
The NTSB’s analysis of the airplane’s navigation system’s light bulbs suggests that the pilot had selected the GPS mode for the initial approach but had not switched to the proper instrument approach mode to allow the autopilot to lock onto the ILS.