A Wiltshire explorer is about to attempt the first-ever crossing of the Atlantic Ocean in a hydrogen balloon.

Sir David Hempleman-Adams, 66, will be joined by American balloon manufacturer Bert Padelt, 62, and Swiss scientist and entrepreneur Dr Frederik Paulsen, 72, for the adventure in September.

The crew, with a combined age of more than 200, will become the oldest people to cross the Atlantic in an open-basket gas balloon if the attempt is successful.

Their route will take them from Maine in the eastern United States, over Newfoundland in Canada, then 2,500 miles across the Atlantic.

They then plan to fly over Ireland and Scottish waters before landing their class AM9 balloon - named the Torabhaig Atlantic Explorer - in Europe.

The journey is expected to take between four and five days and will include scientific experiments between 6,000 and 8,000 feet.

Previous successful flights across the Atlantic have been in helium balloons, so the Torabhaig attempt could set the longest distance covered by a hydrogen balloon.

Sir David will become the only person to have flown across the Atlantic three times in an open-basket balloon.

The Swindon-born adventurer was the first person to reach the geographic and magnetic North and South Poles as well as climb the highest peaks in all seven continents – the Adventurers’ Grand Slam.

In June, he became the first person to be awarded Polar Medals by two monarchs for his expeditions to the Arctic and Antarctic.

Mr Padelt suggested the challenge before the coronavirus pandemic, then began building the balloon while Sir David focused on the control room, weather forecasts, and putting together a team to retrieve the balloon and crew after landing.

Sir David said: “Bert Padelt actually hand-sewed the envelope of the balloon and built the basket.

“He is one of the best craftsmen in the world and it is a work of art from the heart.

“The balloon is built from a special material to contain the hydrogen. Hydrogen is a natural resource and is a by-product of many manufacturing procedures.

“The combined age of the crew is over 200, so lots of experience and wisdom. We will be the oldest team to fly.”

During the crossing, the team will be collecting air samples as part of a scientific study supported by Basecamp Research.

A secondary study, measuring the impact of the Canadian forest fires, will be undertaken in collaboration with the Institute for Climate and Atmospheric Science at the University of Leeds.

Sir David admitted it would be a “tight squeeze” with three people in the open basket.

“Once you get into a routine it’s easier, as one person sleeps, one flies and the other does the scientific experiments,” he said.

“The person who is sleeping will sleep under the bench, which is across one side of the balloon, while the one who is flying will be sitting on top of it.

“There is a small pocket at the end of the basket so you can stretch out to sleep. We will all eat together. The food is similar to survival rations, which are self-heating, plus biscuits.

“The first day, the adrenaline kicks in as there is a lot to do to get the balloon done for the 2,500-mile Atlantic crossing.

“As we get into a routine, we can then admire the views. Once we come up to Europe, it will get busy again.”

Sir David and Mr Padelt are planning to pilot in six-hour shifts, making contact with their flight control centre every hour.

Asked how he was feeling, Sir David said: “Excited, apprehensive, never complacent.

“It’s a huge challenge but it’s a great team and a great balloon.”