Spin is answer to plane tyre blow-outs says inventor, 80

The Royal Air Force has enlisted a retired bank manager in Orkney to help them put a stop to potentially lethal tyre blow-outs such as the one that caused the recent Concorde crash in Paris.

The Royal Air Force has enlisted a retired bank manager in Orkney to help them put a stop to potentially lethal tyre blow-outs such as the one that caused the recent Concorde crash in Paris.

From his cottage in Orkney, 80-year-old Willie Groat has come up with a unique way of reducing the wear and tear on plane tyres every time they hit the runway. And the RAF is so impressed it has taken over his patent and started trials at RAF Cosford in Shropshire.

The characteristic "yelp" sound of aircraft tyres hitting the ground is caused by stationary wheels skidding when they make contact at an average landing speed of 170mph. Mr Groat's response is simple and revolutionary: the wheels and tyres should be rotating before the landing so they don't skid and scorch, he says.

His design, which incorporates cup-shaped flaps on the rubber tyres, relies on the fierce slipstream to put the wheels in motion during the plane's descent.

"I know the Concorde problem was during take-off but aircraft tyres are subject to so much regular stress on landing that hidden weaknesses can cause blowouts at any time," he said.

Corporal Neil Pouney from RAF Cosford said his colleagues in the Advanced Engineering Squadron were amazed to discover there had never been trials of such a system. "There had been some work done using metal spikes on wheels to catch the wind, and some ideas for mechanised pre-rotation of landing wheels, but neither of them had got very far," he said. "Nothing had been tried using something as easy and obvious as this."

They incorporated the idea into a training project with Tornados, the primary air defence and ground attack aircraft. The undercarriages in military planes are proportionately much heavier than civilian ones, due to higher landing speeds and the harsher conditions such aircraft are expected to operate in.

"There was a tyre blow-out at Manchester airport last year with a British Regional Airways passenger flight," said Mr Groat, who ceded his patent to the RAF free. "The nosewheel burst and they were really lucky there were only minor injuries. If my system had been in use it would never have happened."

Aircraft tyres are changed on average every 150 landings. The far higher landing speed of Concorde means the tyres have to be changed every 30 landings.

Not surprisingly, tyre manufacturers are reserving judgement, though Mr Groat says he has had encouraging replies from Goodyear, who make the tyres used on Concorde.

"I received a very positive letter from their HQ in Ohio," he said. "It was obvious they were anxious to put safety factors before profit margins on replacement tyres. They said to keep them posted on developments."