What happened
On September 12, 2013, at approximately 1600 central daylight time, a Pilatus PC-12/47E, registration N617BG, was performing an on-demand passenger flight from Austin-Bergstrom International Airport (AUS) to Lubbock Preston Smith International Airport (LBB). During the takeoff roll on Runway 17L, the aircraft reached rotation speed and established a positive rate of climb. However, as the aircraft accelerated to 95 knots, the airspeed stagnated, and the pilot experienced a series of pitch oscillations accompanied by stall warnings and stick shaker activations.
After multiple instances of the aircraft pitching down and the pilot recovering to level flight, the pilot aborted the takeoff. The aircraft settled onto the runway and came to a stop on the remaining runway surface. The incident resulted in one minor injury to a passenger, while the pilot and eight other passengers were not injured.
The investigation
An investigation into the aircraft's condition and loading revealed that the right main landing gear wheel sustained thermal damage, with melted metal in the tire sidewall and melted fuse plugs. No mechanical anomalies were found in the aircraft's systems that would have prevented normal operation.
Investigators found that the aircraft's weight and balance calculations were inaccurate. Although the operator's specifications required the use of actual weights for passengers and carry-on items, the trip schedule provided to the pilot did not include updated weights for three replacement passengers, nor did it account for carry-on baggage. Specifically, several coolers and food items weighing approximately 490 lbs were not included in the pilot's calculations.
Post-incident analysis determined that the aircraft was approximately 100 lbs above its maximum ramp weight and the center of gravity was approximately 4 inches aft of the allowable aft limit. Additionally, the weight and balance documentation required by FAA regulations was not on board the aircraft during the flight.