The ambulance has speeded up travel times

The BBC's health correspondent Adam Brimelow has been to see it in action.

Every week three times a week the sea ambulance heads out from the harbour at St Mary's, the biggest island.

On board, there is a local GP, a health visitor, nurse and a midwife. This routine trip used to take up to an hour - now it's more like ten minutes.

Those who live on the islands say the sea ambulance will be vital in helping people quickly.

Just two thousand people live on these islands, but in the first week there were five emergency call-outs, for broken bones, an asthma attack and two mothers in labour.

Anna Eddy rang for the ambulance when her waters broke late at night. Forty minutes later she was safely across the bay in hospital, and her baby Dillon was born the next day.

Dillon Eddy was born after his mother was taken to hospital by sea ambulance

"It was one o'clock in the morning and very cold so to be inside, and see all the equipment was a great reassurance", she said.

A couple of days earlier she would have been on the old ambulance - an improvised affair, slow, cramped, and with just a tarpaulin for cover.

'Good value'

It will not be missed by the local GP, Dr Randolph Hessing. He says there was nowhere to place a patient on a stretcher.

"In rough weather we ended up balancing them on the engine box or holding on to them from one side and wedging them in somewhere else".

But for all its speed, comfort and modern equipment this boat hasn't arrived to universal acclaim.

Some people think it's ugly. Some question the cost - over quarter of a million pounds - more than four times the price of a conventional ambulance.

However Tony Smith, the ambulance technician who works full time on the boat has no doubts that it's good value for money.

"We've been out five times in the last week", he says. "Compare that to the local lifeboat which cost about two and a quarter million pounds. The St Mary's lifeboat goes out about twelve times a year."