A new £77m superhangar for repairing military aircraft has been officially opened, amid concerns over its future.
The hangar is part of a project to promote aviation work in Wales
The hangar, which covers 65,000 square metres, is at the Aerospace Wales St Athan business park, in the Vale of Glamorgan, south Wales.
It can accommodate more than 50 jets at any one time and has been built for the Defence Aviation Repair Agency (Dara).
But in December, the UK government said it may sell Dara, which is a civilian arm of the Ministry of Defence (MoD).
Dara was set up to cut the costs of maintaining and repairing the UK's military aircraft and employs 3,800 staff at four sites across the UK. Thirteen hundred staff are now employed at the St Athan site.
The new hangar is a key part of Project Red Dragon, which is the Welsh Development Agency's (WDA) plan to create a world-class aviation centre at RAF St Athan.
But last year, 500 jobs went at St Athan after Dara lost important RAF contracts for repairing Tornado and Harrier fighters.
On Thursday, the union representing specialist civilian staff in the MoD, called for plans to privatise Dara to be scrapped.
Prospect's Jim Cooper said Dara was in a perilous position, as it was in danger of losing the facilities which were designed to make it a world-class aviation centre.
'No final decision'
He said: "Sell-off would see the loss of that expertise, the break-up of highly skilled teams and destroy the public sector benchmark for defence aviation repair and maintenance work.
A spokesman for the MoD said that work on the Tornado F3 would remain at St Athan for the jet's lifespan, but that the situation after that was not yet known.
"Unless additional work can be found, it is unlikely we can maintain a viable business at St Athan beyond 2008/9.
"But detailed workload plans are now being developed and we stress no final decisions have been made."
One high-tech company from Bath has already confirmed it is taking space and ten other companies are showing an interest in moving there.