Plane crashed after propeller fell off in mid-air

The Aeronca 65C aircraft had taken off from Runway 26 at Birchwood airfield, a private airstrip north of Barlby, on October 21 last year.

As it climbed to 450 feet, the pilot went to reduce power - then noticed that the engine was racing.

"The pilot immediately closed the throttle and flew the aircraft to maintain its best gliding speed of 65 to 70 mph," says a report into the incident by the Air Accident Investigation Branch (AAIB).

"He evaluated possible landing sites ahead but chose to return to the airfield as he felt his options were limited."

After lining up on one runway, he decidd the aircraft was going too fast, so headed for a second runway instead.

He managed to touch down. "(But) despite the use of braking, the aircraft went through a hedge at the far end."

After switching off the fuel and the electrical master, both the pilot and his passenger were able to scramble out of the aircraft to safety.

"It was then that they noticed the propeller was missing," says the AAIB report.

The nose of the crashed aircraft, showing the missing propeller

The report says that investigation revealed that all six propeller bolts on the aircraft had failed.

"It is possible that the incorrect bolt length was chosen due to a misinterpretation of the engine manufacturer’s installation document," the report says. The manufacturer has revised the installation document to 'include a drawing to aid the correct length of propeller bolt to be selected'.