The pilot of a microlight aircraft had a narrow escape when a spare helmet bounced out of the back seat and smashed into the rear propeller as he was taking off from Rathcoole airfield near Mallow in Co Cork.
The 48-year-old pilot was making a take-off run over rough ground on the side of the grass runway on November 5th when he heard a loud bang and the engine shut down.
The engine is mounted at the rear of the aircraft and the spare helmet, carried in a ballast bag in the unoccupied rear seat of the cockpit, had come loose, bounced out and shattered one of the four propeller blades.
"It is fortunate this incident happened while the aircraft was still on the ground," according to a report from air accident investigator Paddy Judge yesterday.
In May 1998 two men were killed when their two-seater microlight crashed in Sligo Bay while taking part in an aerial treasure hunt. The aircraft nose-dived into wet sand about 10 minutes after take-off. A fuel cap that had become dislodged and broke off a portion of one of the rear propellers was blamed for the tragedy. A fuel cap had been lost in flight from the aircraft on a previous occasion.
"Pusher propeller microlight aircraft are intrinsically liable, due to the location of the propeller behind the open cockpit, to foreign object damage (FOD) emanating from the open cockpit or its vicinity, " Mr Judge reports.
"It should also be remembered that carbon composite propellers do not have the impact resistance of metal or wooden types.
"It is therefore vitally important that the pilot ensures that any objects carried in these cockpits are adequately secured and restrained. As these objects are in the rear seat behind the pilot, they are out of his line of sight once he is strapped in."
The report says the chain of events that led to the Cork incident probably started when the pull string of the ballast bag broke in the past.
The pilot was then distracted and did not ensure that two plastic snap-on buckles were attached over the top of the bag. The supplier of the ballast bag has since redesigned it.