Two men have already died and hopes of finding more survivors in the freezing waters are fading.

The BBC's George Eykyn: Organisers will not call off the race

Robin Poke of the Australian Maritime Safety Authority said the navy will have difficulty looking out for "smaller targets".

"Vessels are a preferable target," he told BBC News 24. "Even a life-raft is a preferable target but when you simply have people bobbing around there in conditions which are improving but still fairly ordinary, then the task is really fairly hopeless."

On Monday rescuers looking for the missing crew of the veteran Winston Churchill cutter found two life-rafts, one in the day and one in the late evening. Altogether, six were rescued but the three others had been swept off the raft in the early hours of Monday morning.

The fourth man missing is the British Olympic yachtsman Glyn Charles, who was swept off his boat, Sword Of Orion, on Sunday. He is now presumed drowned.

Robin Poke: "Smaller targets make the search a hopeless task"

The Winston Churchill, which took part in the inaugural race in 1945, foundered in mountainous seas on Monday morning.

Its owner and skipper Richard Winning was among the four rescued from the first lifeboat found.

He told an Australian news agency of his 24-hour ordeal.

Survivor Richard Winning: "Bloody frightening"

"The worst thing of the whole affair was that after we got into the life-raft and became separated from the others, the damned thing capsized twice on these great seas at night which is bloody frightening, let me tell you," he told the Australian Associated Press news agency.

"You have got four of us underneath this little canopy and the next thing is you are upside down. So one poor bastard has got to go out and ride it while the other three are inside. That happened twice and it was twice too many."

Two dead in raging seas

Two sailors died on the stricken Business Post Naiad. The skipper, Bruce Guy, had a fatal heart attack as his boat rolled in 30ft-high waves. Another crew member, Phil Skeggs drowned, strapped to the deck in a safety harness.

The remaining seven crew were plucked from raging seas by a helicopter.

Some yachts suffered severe structural damage

A frigate and 25 aircraft joined the rescue effort in atrocious weather conditions. Helicopters winched up more than 50 men to safety from the decks of their wrecked yachts.

Winds gusted at 80 knots and waves up to 10 metres high caused havoc to the fleet.

The horrific weather forced 67 of the 115 competitors to pull out of the race or take shelter.

Severe damage

Robin Poke: "Smaller targets make the search a hopeless task"

Many of the yachts lost their masts, and had their rigging smashed to pieces. Some have suffered serious structural damage falling from the tops of giant waves and are taking on water.

The director of the contest said conditions were the worst the race had seen since 1993 when gale force winds forced 66 of the 104 starters to retire.

The weather bureau said there was no sign that conditions will improve over the next few hours.

The American maxi Sayonara, and the Australian maxi Brindabella, seem to have got ahead of the worst of the winds.

On board the Sayonara, currently in the lead, was its owner and skipper US computer executive Larry Ellison and Lachlan Murdoch, son of media magnate Rupert Murdoch.