Fife-based John Williams clocked a top speed of almost 112mph during the St Andrew’s Day flight, beating his personal best and toppling the previous record in the same breath.

Though he is the first to admit that records were the last thing on his mind, the retired BP site manager is now expecting official confirmation that his 112mph swoop is the fastest yet recorded for a trip of 1500km or more, a standard measure in the ­gliding world. The previous record-holder, a German, peaked at 110mph.

Mr Williams’s 1550km dash through the skies of Argentina has also set a new British distance record, and it propels him into an elite league with the top dozen or so pilots worldwide.

Speaking from South America, where celebrations are continuing, Mr Williams said of his flight: “It looked like a good day, and I’d gone out hoping to fly the 1500km as fast as possible, but the thought of record-breaking was not in my mind.

“It’s pretty wonderful that an old fart in his 50s can have a crack at a world record, though. There’s not many sports where you could say that.”

Originally from Ireland, Mr Williams settled in Fife, where he flies from the Scottish Gliding Centre at Portmoak, on the banks of Loch Leven.

The country offers some of the best gliding opportunities anywhere in the UK, he said, and its unique landscape helped build the skills needed for the record-breaking feat.

Despite some superb gliding conditions, however, Scotland’s small size makes it unsuitable for world record attempts.

Mr Williams said: “On Easter Sunday 2007 I did a flight up to Callander, and to the far north, which broke the British distance record, but then I ran out of country, because Scotland is geographically quite limited.

“At that time, I looked for other places to fly, and the Andes are just unbelievably long. Argentina alone is 35 times the size of Scotland.”

While some gliders choose to seek out rising currents of warm air, known as thermals, others -- like Mr Williams -- use drafts coming over mountain ranges for their lift. In this way modern gliders, with a typical wingspan of around 20 metres and a price tag of up to £100,000, can stay ­airborne for several hours at a time.

In South America, westerly winds hit the side of the Andes and then bounce up on the east side, giving a run of several thousand kilometres and making the country a mecca for international gliding enthusiasts.

But although the snowcapped Andean scenery provides a spectacular backdrop, there is little chance for the solo pilot to enjoy the view.

“It’s very hard mental concentration,” Mr Williams said. “You’re doing lots of things at the same time, dealing with air traffic control -- who only speak Spanish -- and trying to navigate at the same time. You’re trying to work out ­tactics 10 or 15 miles ahead, because there are no signposts up there, and you have to look at the shape of clouds to decide where updrafts will be. You’re running on a knife-edge all the time.”

It was only when he landed, through a dangerous blanket of cloud cover, and downloaded his flight log, that Mr Williams realised he had ­broken the speed record by almost 2mph.

He is now awaiting formal confirmation from the World Air Sports Federation, but the Scottish gliding community has already heaped praise on the new record holder, who is the first Scot ever to hold

the honour.

Douglas Tait, chairman of the Scottish Glider Union, compared Mr Williams’s ­success to someone running a marathon and setting a new speed record in one fell swoop, and described it as “a really, really big deal” in the gliding world.

“This is very important for Scottish gliding, and as the premier gliding club in ­Scotland -- and one of the biggest in the UK -- we’re very proud of John’s achievements,” he added.

The previous holder, Klaus Ohlmann, is regarded as the leading light of the gliding world, and the Scottish pilot described it as “a great ­pleasure” to take his title.

“He’s a superb guy, a retired German dentist, and he has more records than you can imagine. Taking one from him is very, very nice. It’s like if you want to win a Grand Prix, beating Michael Schumacher is a nice touch,” he said.

Mr Williams remains in Argentina, and has not ruled out further record attempts in future.