A group of researchers who wanted to be the first to cross the Atlantic in an open hydrogen balloon expressed their “extreme disappointment” after the attempt had to be aborted.

British explorer Sir David Hempleman-Adams, 67, who lives in Wiltshire, and two friends set off shortly after 02:30 UTC from Presque Isle, Maine, in North America [03:30 BST].

But after about seven hours in the air, the crew had to land at 09:40 UTC. [10:40 BST] near New Brunswick, Canada, due to weather conditions.

A spokeswoman for the crew, who are doing well, said: “They will try again, but at the moment it is too early to say when.”

She added: “It was a very difficult decision and they are obviously extremely disappointed, but safety is of course paramount.”

The attempt by the crew of the Torabhaig Atlantic Explorer was monitored by air traffic control in Bristol.

The spokeswoman said the conditions required a higher altitude than planned, which would have required “increased ballast consumption”.

The crew therefore decided to land the balloon, as they concluded that they did not have enough ballast to make it to Europe.

Before the attempt, Sir David said: “At 67, I am still young enough to attempt a daring flight across the Atlantic in a hydrogen balloon.

“Age is just a number and the spirit of discovery never dies.”

Sir David has crossed the Atlantic twice before in an open basket balloon, but this was the first attempt to cross the Atlantic in a hydrogen balloon.

He was accompanied by the American balloon manufacturer Bert Padelt and the Swedish explorer, scientist and entrepreneur Dr. Frederik Paulsen.

Last year, the attempt was also postponed due to bad weather.

Sir David said: “My two previous transatlantic flights were solo and my companions on this trip have no idea how loudly I snore.

“May the weather be on our side this time, because everything else is planned and ready.”

The highest altitude the team flew at was 10,000 feet (2,048 meters) and a distance of about 125 nautical miles.

During the trip, they wanted to conduct experiments. One study, for example, was to find out how particles from forest fires move through the atmosphere and affect diseases such as asthma.

Clive Bailey of Bailey Balloons was at the Bristol base monitoring progress.

He said: “Over eight hours, an incredible amount of work went into preparing the balloon for launch. A tanker truck was used to fill the balloon with hydrogen while the team sorted out all the technical equipment.”

“The flight control team was awake all night to ensure the safety of the balloon and crew and to monitor progress.”