HE’S crossed the Atlantic in a balloon, the English Channel by amphibious car and will soon leave earth’s orbit in his private spaceship.

And for his next trip, Sir Richard Branson is voyaging to the bottom of the sea.

Like a real Captain Nemo, he has secret plans to build a submarine capable of exploring the lowest depths of the oceans. The idea is said to have been that of his friend Steve Fossett, the American adventurer missing since his plane disappeared over the Nevada desert in September.

Last week Virgin’s billionaire boss revealed he had set up a “Skunk Works” division similar to Lockheed Martin’s cutting edge research lab. The division is headed by Alex Tai, a former pilot who was chief operating officer of Virgin Galactic, Branson’s space-tourism business.

A Virgin insider said the ocean venture was one of several launches being considered and was in its early planning stage.

Only a handful of submersibles are capable of reaching the lower ocean depths. They include America’s Alvin, Japan’s Shinkai, France’s Nautile and Finland’s MIR submersibles, which can dive to a maximum of 20,000ft.

Oceans cover three-quarters of our planet, more than half are over 10,000ft deep and, according to a US government report,95% remain unexplored.

Among the many things that subs could discover are vast mineral deposits and unknown life forms. Branson’s craft would first be used for research purposes, with the possibility of undersea tourism in the future.

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