Dara workers protested outside the defence committee's meeting

Representatives of workers at the Defence Aviation Repair Agency (Dara) at RAF St Athan gave evidence to the defence select committee group.

The Commons committee visited the base before holding its meeting in Barry.

Up to 500 jobs are to go at the site when the �130m fast jet operation switches to an RAF base in Norfolk.

Dara is expected to close by April 2007, but unions have claimed that work which has already been taken from Dara was not being carried out by the RAF elsewhere.

They have said RAF staff did not have the specialist skills nor the facilities needed. Instead, they said work was being done by private companies.

The defence committee toured the base before convening

Trade union Amicus told the defence committee that it had evidence that repair times on Harrier jets at RAF Cottesmore were higher than at Dara.

It told the committee the turnaround time at St Athan was about 100 days and due to fall to about 60 to 80 days, but turnaround time at Cottesmore was about 155 days.

Amicus official Bryan Godsell said: "We can identify by aircraft numbers where the flying time is now exceeding the servicing interval and we do certainly believe that this is putting pilots and indeed the public at risk."

'Harrier fleet'

Committee chairman James Arbuthnot said it was "really very unlikely that the MoD will change it's mind about the future of St Athan as a result of the report".

The inquiry's role was to "explore the rationale" behind the closure, he said.

In written evidence, the unions - Amicus, Transport and General Workers, PCS, and Prospect - claimed: "The cost of servicing the Harrier fleet at RAF Cottesmore has increased to �17 million whilst the cost for Dara for the same work was �0.5 million."

The decision to shed jobs at Dara has been strongly criticised by local MPs, with the Vale of Glamorgan's John Smith speaking of his "utter dismay" and Cardiff North's Julie Morgan describing "betrayal and outrage".

Welsh Economic Development Minister Andrew Davies has said he regretted the Ministry of Defence's decision but he was confident of generating investment at the site.