Piper PA46-500TP N46ME accident near Rock Springs, Wyoming

Probable cause

The overstress fracture of the right aileron midspan hinge bracket due to modal vibrations created by a deflated right main landing gear tire during the takeoff roll.

NTSB analysis

During the takeoff roll, as the airplane approached 70 knots, it started slowly pulling to the right. The pilot immediately aborted the takeoff and stopped the airplane on the runway using brakes and reverse propeller thrust. The pilot inspected the airplane and found that the right main landing gear tire had blown, and the right aileron had buckled at the aileron midspan hinge location. There were no scuff marks or indentations to indicate that the hinge or area around the hinge had been struck by debris. The hinge was still attached to the aileron, but the attach bracket that connected the hinge to the wing had fractured. Metallurgical examination revealed that the failure of the hinge bracket was the result of overstress forces applied to the hinge. Overstress failure of only the midspan hinge is somewhat unusual when none of the other hinges were damaged, which suggests modal vibration forces concentrated at this particular hinge. It is likely that the flat tire could have induced the vibratory mode in the aileron at the midspan hinge.

Text from the NTSB. Open the NTSB docket for WPR11LA218 for the full record.