On October 31, 2002, an Aeronca 7AC (registration N83651) was involved in an aviation accident near Warner Robins, GA. Investigators recorded the probable cause as: The pilot's failure to follow engine start procedures for a overprimed engine, and his improper use of the throttle control during an attempted start. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During engine start, an airplane taxied unmanned at high speed, dragging the pilot, and collided with a hangar and a parked airplane. A fuel stain was found near the wheel chock.
Incident Description
The pilot chocked the main wheel and initiated starting procedures, which included manually pulling the propeller through. After several unsuccessful attempts to start the engine, the pilot primed the engine, partially opened the throttle, and pulled the propeller through. The engine then started and accelerated to high rpm. Subsequently, the airplane taxied unmanned at high speed, dragging the pilot, before colliding with a hangar and a parked airplane. The pilot reported no mechanical malfunction with the airplane.
Examination Findings
Examination of the cement pad where the wheel chock was located revealed a fresh fuel stain approximately eight feet long and four feet wide. Several boot and shoe tracks were observed through the fuel stain.
Advisory Circular Reference
Federal Aviation Administration Advisory Circular AC165-12 states that the corrective action for clearing an overprimed engine includes opening the throttle fully and turning the propeller to expel excess fuel.