IT'S A yacht the like of which the world has never seen before.

Everything about it, including the £30m price tag, is on a huge scale and it's taking shape in the heart of Southampton.

The hull of Mirabella V is so vast a double decker bus could be driven down its length and there would still be room to spare.

Being built by Vosper Thornycroft (VT) craftsmen at Woolston, the yacht is destined to become the plaything of the world's mega-rich who will have to pay a quarter of a million dollars a week to charter the luxurious superyacht.

Mirabella V has been commissioned by American businessman Joe Vittoria, pictured, the former chairman and chief executive officer of Avis car rental, who will operate the massive 246-foot long yacht in the jet-set playgrounds of the Caribbean during the winter and the Mediterranean in the summer.

A total of 12 passengers, will be pampered in sumptuous surroundings, including six staterooms furnished with rare antiques, by the same number of crew. The whirlpool bath is so big it needs ten tons of water to fill it, the same amount needed for the yacht's swimming pool, and there is even an outdoor cinema for watching the latest films on deck.

The yacht's 292-foot tall mast is so big that it would be impossible for it to pass under the highest part of Southampton's Itchen Bridge close to VT's yard.

"I come over every couple of months to see how things are progressing and I have to say Vosper Thornycroft is doing an absolutely wonderful job,'' said Mr Vittoria, who hopes to be able use Mirabella V for about a month every year.

"Every time I see the yacht it seems to be getting bigger and bigger, it just takes my breath away.

"Sadly when she leaves Southampton I don't think she will be seen here again as she will go where the money is and you will be surprised how big the charter market is for these king of superyachts.

"I have been told there are 497 billionaires in the world and I only need 20 of them to book the yacht every year!''

The yacht's tender, carried on the back of the yacht, will be 29-foot long, weigh three-and-a-half tons with a 400 horsepower engine.

MIRA FACTFILE:

Builders: VT Shipbuilding, Southampton

Length overall: 246 feet. Beam: 48 feet

Maximum draft, centreboard down: 32 feet

Maximum draft, centreboard up: 12 feet

Full load displacement: 740 tonnes

Sail area: 3,0042 square feet

Crew: 12. Speed: 16 to 20 knots

Owner: Joe Vitttoria