London, England -- Virgin mogul Richard Branson recently unveiled a new ocean play thing for the intrepid super rich: A deep-sea submarine.
"Necker Nymph," which is due to be delivered later this month, is an "underwater plane" that can dive up to 40 meters below the surface, is the latest addition to Branson's luxury collection which includes a private island, a superyacht and a spaceship.
For those wealthy enough to indulge, the experience aboard the submarine, which is nimble enough to perform "dolphin-like flips," will be like "flying underwater," said Branson company Virgin Limited Edition.
But even for those with deep enough pockets, it doesn't come cheap: $25,000 for a week's charter and another $88,000 for the sub's superyacht launch vessel, "Necker Belle."
The $631,000 flying sub, the first of its kind, uses fighter jet technology and was designed by Hawkes Ocean Technologies. It is transparent enough to allow divers a 360-degree view of marine life and Virgin is marketing it as a way to view dolphins and whales close up.
The new sub is also green: It is positively buoyant which stops it from mistakenly landing on reef and and it is relatively quiet allowing it to pass through fragile ecosystems without causing too much upheaval, according to Virgin.
Potential deep-sea divers must take half-day safety courses beforehand and can then dive for up to two hours at a time.
The submarine will be delivered to Necker Island, Branson's private Caribbean hideaway later this month.
"Necker Nymph" is not Branson's first foray onto the frontlines of adventure technology.
Last December, he unveiled "SpaceShipTwo," a spaceplane that promises to take civilians into orbit for a cool $200,000 by 2011.