The boat should be finished in July

"It is about enjoying life on the sea and proving that anybody can sail."

The 58-feet (17 metres) catamaran is being designed by Nic Bailey from Dartmouth in Devon.

Mr Browne said he did not intend to set out on any single-handed voyages, but wanted to ensure that, if necessary, he could sail the yacht on his own.

"There is no reason technically why, as a wheelchair user, I can't be the skipper.

"It is a unique project.

"Boats have been adapted for disabled people before, but there has never been a yacht designed from scratch to do this job."

It is an enormous challenge

Designer Nic Bailey

He expects the catamaran to cost more than �500,000 and said it would be owned and used by a charity he set up, Sporting Activities for the Disabled.

Work is well under way on the carbon-fibre boat at Multimarine's yard in Cornwall and the plan is to finish in time for a launch next July.

Mr Bailey said: "It is an enormous challenge and I haven't done anything quite like this before.

"Every part has had to be designed from scratch so it is quite tricky.

'Racetrack' perimeter

"We have had to think about how Mike can do things that an able-bodied person takes for granted."

The catamaran will have a "racetrack" running around the perimeter to accommodate a wheelchair, hydraulic systems to control the sails and lifts to give access to the cabins and dockside.

In addition, the wheelchair will lock on to a small chassis mounted on a track so it can move across the cockpit but can still be controlled in bad weather.