A FIRM in Ryedale is celebrating after designing and making an underwater vessel designed to rescue people from submarines in distress.

Perry Slingsby Systems Limited, in Kirkbymoorside, has just built NATO's "Rescue Submersible" - which has the capability to rescue 15 people at a time - for the governments of the UK, Norway and France.

The submersible has been built to replace the vessel that was involved in the rescue efforts to save the crew of the Russian nuclear submarine, Kursk, which grounded on the sea bed in August 2000.

In a rescue operation, the submersible - which cost £30 million to build - can be flown by aircraft to the port nearest the submarine in trouble, after which it would be deployed on to a ship with lifting equipment.

The ship would then sail out to the area, where the submersible would submerge and dock on to the submarine's rescue hatch, from which it would retrieve the rescuees.

John Howard, project manager at the company, said that about 50 of its employees had been involved in the project: "We're delighted that it's all finished now. It's been a culmination of three years' hard work and we feel a massive sense of achievement. The crew of the distressed submarine enters the rescue submersible through the transfer skirt protruding below the submersible. But we hope it will never be used in the future."

The 30-tonne, nine metre-long submersible was yesterday transported to Faslane naval base, at Clyde, in Scotland, where it will undergo further trials, which will also be undertaken at sea.

The vessel will be based at Faslane, from where it will engage in NATO exercises at least once a year.

The submersible has been funded by the three governments, but the UK has managed the three-year project to design and build the vessel, with the main contract being awarded to Rolls Royce.

This is not the first time Perry Slingsby Systems Limited has built a submersible - it started making them back in the 1970s.

At that time, the vessel was designed for a commercial purpose - to undertake offshore pipe line surveys.