One firm will use a hangar to modify wings of Boeing 737s

Two aerospace companies said the facilities and skilled workforce were their reason for making the move.

ATC Lasham, whose customers include British Airways and Ryanair, will use a hangar at the site to carry out wing modifications to Boeing 737s.

The base houses the Defence Aviation Repair Agency (Dara), which is shedding jobs due to losing a repairs contract.

ATC Lasham said it was to use the 100,000 sq ft (9,300 sq m) "Twin Peaks" building, which has the capacity to house up to four Boeing 737 or 2 Boeing 757/767 aircraft at the same time.

The firm said it would create 50 new aircraft maintenance jobs initially, building up to 250-300 jobs over the next 18 months

The TES Aviation group, which provides commercial and technical support to airlines, is the second firm establishing a base at the park.

The base is also home for the aviation repair agency Dara

The Welsh Assembly Government and Ministry of Defence said they had been trying to attract new civil aerospace jobs to the site for sometime, to secure its long term future.

The WDA bought the 150-hectare (370-acre) site, including the RAF base, in 2003 and leases part of the site back to the MoD, which runs Dara.

Hundreds of posts are being lost at Dara because of a UK Government decision to move work on fighter aircraft from RAF St Athan to another RAF base in Norfolk, prompting a campaign by workers and the area's MP to reverse the decision.

Dara currently uses the Twin Peaks" building to service the MoD's VC10 fleet, but will move this work into the �70m "super hangar" on the site to accommodate the commercial sector work.

Industry profile

Economic Development Minister Andrew Davies said the jobs move on Wednesday was a vote of confidence in the base.

Mr Davies said the double investment, to be announced at an aviation trade fair in Berlin, would raise the industry profile of Aerospace Wales.

He said: "I think it's the start of a very exciting development at St Athan.

"Obviously there's a huge amount of uncertainty given Dara's position but the fact that ATC Lasham and TES Aviation group are going to locate part of their operations at St Athan is a huge boost for the area but more particularly for the workforce."