According to the passenger, the pilot of the Super Cub was making a second low pass over friends just before the accident in Sterling, Alaska. Witnesses reported seeing the airplane flying very slowly, about 300 feet above the ground, with the engine at a low power setting.
The right wing dipped, and it subsequently entered a near-vertical spiraling descent, hit a tree, and came to rest in a snow bank.
Both the pilot and passenger received serious injuries. The pilot was unable to remember anything about the accident due to injuries.
The airplane sustained substantial damage to the wings, lift struts, and fuselage.
Investigators determined that given the lack of evidence of any mechanical problems, the passenger and witnesses’ account of the accident, and the airplane’s near-vertical descent, it is likely that the pilot inadvertently stalled the airplane at low altitude and was unable to recover.
The NTSB determined the probable cause was the pilot’s failure to maintain adequate airspeed while maneuvering at low altitude, which resulted in an aerodynamic stall.
NTSB Identification: ANC13LA026
This February 2013 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.