Safety Topics: Failure of Fan/Hub Assembly

An Optica aircraft commenced its take‐off roll from approximately one third along the runway (due to the activities of a gliding club). The take‐off and initial climb were normal until at an altitude of about 160 ft there was a loud ‘bang’ followed by a severe vibration. The pilot immediately lowered the nose of the aircraft and throttled the engine back to idle in order to reduce the vibration. It was apparent that a forced landing was necessary but the pilot assessed that the remaining runway ahead was insufficient and would result in an overrun onto a public road. He therefore put the aircraft into a 30° banked turn to the left with the intention of making a downwind landing on another runway. The observer made a radio call informing the tower of the pilot's intentions. With full flap selected, the aircraft touched down two thirds along the runway although not aligned with it, at an airspeed of 60 knots. With a wind of 230/15 knots this resulted in a ground speed of 75 knots. The engine was still at idle rpm as the aircraft rolled onto the grass on the left side of the runway and came to a stop. There were no injuries and no apparent additional damage although a small amount of fuel was observed to be leaking from the bottom of the engine pod.