Prospect accused the MOD of causing disruption to Britain’s proven and effective training structure for the armed forces, purely in order to avoid embarrassment at the closure of its Red Dragon RAF air repair centre at St Athan, in the Vale of Glamorgan.

Steve Jary, Prospect National Secretary, said MOD’s refusal to entertain an in-house bid for defence training would result in the unnecessary relocation of thousands of technical and non-technical experts.

"MOD wasted over £100m of taxpayers’ money on a centre of aviation excellence at St Athan which has been closed a year after opening. Now it has awarded the training contract to the Metrix consortium because its bid will utilise a site that would otherwise have stood embarrassingly empty. This is no way to run the training structure that has served Britain’s armed forces well for many decades. It puts short-term political gain before the needs of the people who supply and receive military training."

More than 3,000 civilian experts supply training for the three services across 30 sites. These will be slimmed down to seven sites, requiring a huge transfer of personnel and the rundown of facilities at existing establishments. This will hit RAF Cosford, Shropshire, particularly hard as that is where the bulk of engineering training now takes place.

Prospect and the other defence unions argued for an in-house bid that would invest in existing facilities, but this was rejected as MOD could not raise the capital funds required.

Accommodation for thousands of service personnel students, instructors and specialist teaching and lecturing staff will now have to be built at St Athan. "No wonder the cost of this PFI is sky-high," said Jary. "At £16 billion it is exactly one third of the total cost of the £48 billion in PFI projects which the government has so far committed."

Prospect represents specialist training staff in MOD, in particular lecturers and teachers in aeronautical and mechanical engineering, communications and other technical skills and languages.