Aviat Aircraft Inc A1 N337AM accident near Williamsport, Pennsylvania

Probable cause

The pilot’s failure to verify that the parking brake was disengaged before landing, which resulted in a runway excursion.

NTSB analysis

The pilot of the tundra-tired, tailwheel-equipped airplane reported that, during touchdown, he saw that the left emergency brake was partially engaged. He added that the left wheel was locked and that the airplane exited the left side of the runway. Subsequently, the right landing gear collapsed, and the right wing tip struck the ground.

He added that, before the previous takeoff from a grass airstrip, he had performed his preflight checklist, which was normal. But, "upon reflection," he realized that he had changed his normal routine by shutting down the engine, setting the parking brakes, and exiting the airplane after completing the checklist. After re-entering the airplane, he only did a "visual left to right flow check." He then pressed and released the brakes and applied power holding the left rudder and brake down to turn the airplane in the direction of the departure and then departed after a "very short ground roll downhill."

He further added that, by immediately turning left during the takeoff roll, he "may not have released enough pressure on the parking brake to turn it completely off." He believed that, due to the combination of the large smooth tire, wet grass, and downslope hill, he was unable to determine that the emergency parking brake was engaged.

The airplane sustained substantial damage to the fuselage and right wing.

Text from the NTSB. Open the NTSB docket for GAA18CA022 for the full record.