The owner of Chelsea football club, Roman Abramovich, is having a new £200m mega-yacht built, complete with a missile detection system to protect him against pirates and terrorists.

The vessel, under construction in Germany, will have radar designed specifically to warn of incoming rockets. It is being equipped with armoured protection around the wheelhouse and the billionaire’s cabin, together with bullet-proof windows.

If assailants do breach the security cordon and climb on board, Abramovich, 41, and his girlfriend, Daria Zhukova, 26, a former model, could escape in a yellow submarine that is launched underwater and can dive to 160ft.

The yacht - called Eclipse because it is intended to overshadow any other private boat - is due for delivery next summer. It is being built in the Hamburg shipyards that produced the Bismarck, Hitler’s “invincible” second world war battleship which was sunk by the Royal Navy in the north Atlantic in 1941.

Abramovich, who was ranked second in The Sunday Times Rich List this year with a fortune of £11.7 billion, is taking no such chances.

Should he decide to sail to the 2010 World Cup in South Africa, he wants to be forearmed against attack by such armed gangs as the Somali pirates who seized a Ukrainian cargo ship loaded with 33 Russian T-72 tanks 10 days ago.

Even the Mediterranean, where he usually keeps his fleet of luxury vessels, is becoming less safe. In August a masked gang boarded a £20m yacht, the Tiara, off the southern coast of Corsica and robbed the guests and crew of £100,000 before escaping in a speedboat.

According to the International Maritime Bureau, pirates attacked 269 vessels last year, took nearly 300 hostages and killed five people.

Under maritime law, nonnaval ships are banned from carrying firearms. Some yacht owners are adopting such measures as high-powered water cannons, ear-splitting klaxons and lubricant foam intended to make boarders slip.

Secrecy surrounds the Eclipse project but sources say that the missile defence system is being installed by AST, a company which has close links to both the Blohm + Voss shipyard, where the yacht is being built, and the German defence ministry.

The company said that there was a new pirate menace on the world seas and “private yachts are not spared”. It added that it had designed and produced an antiballistic missile system for mega-yachts which had been “customised to meet the threat scenarios of private owners”.

Friends of Abramovich said last week there were no missile defence systems or submarines aboard his collection of yachts - the 377ft Pelorus, the 282ft Ecstasea and the 160ft Sussurro.

One said: “We have read reports of such devices but we have always taken them with a grain of salt.”

The Eclipse, as the flagship of Abramovich’s fleet, will be different. At 550ft the vessel will be more than half the length of the Bismarck and 15ft longer than the Emir of Dubai’s yacht, the biggest afloat today.

In 2006 Abramovich gave away another of his yachts, Le Grand Bleu, to Eugene Shvidler, 44, a fellow Russian billionaire living in Britain.

The Chelsea owner has ordered that no expense be spared. There will even be twin helicopter pads in case he wants to land two at once. The Eclipse will have a crew of 70, space for Abramovich’s guards and cabins for 24 guests. A British firm, Terence Disdale of Richmond, southwest London, has been awarded the contract for the interior design. Neither it nor a spokesman for Abramovich would comment.

However, Diane Byrne, megayacht editor for Power & Motoryacht magazine and editor of Megayacht News, an online magazine for boat owners, said: “Protection is something owners are understandably concerned about. Piracy isn’t a problem limited to Somalia. It can and unfortunately does happen around the world. Thankfully there are resources that owners and their crew can turn to for equipment and training, so they can better protect themselves.”

Saddam Hussein’s 270ft yacht Qadisiyah Saddam had a missile defence system, while the 482ft Prince Abdulaziz, the royal Saudi yacht, is also a ship in the Royal Saudi Navy and is purported to carry French-made Exocet missiles.

So far the credit crunch has had little effect on the world of mega-yachts. According to ShowBoats International, 916 new boats longer than 80ft are on order in 2008, an 18% rise from last year.

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