The long-term future of an RAF base in Northumberland, which was threatened with closure, has been secured.
Local MP Alan Beith led a campaign to save the base
There were fears hundred of jobs would be lost at RAF Boulmer, near Alnwick, under plans to transfer some operations to Lincolnshire.
Only the search and rescue unit would have remained at the site after 2012.
But the Ministry of Defence (MoD) has now decided to retain the base as the hub of the Air Surveillance and Control System (ASACS).
Local authority figures predicted the transfer would take £18m out of the local economy.
The Liberal Democrat MP for Berwick, Alan Beith, who led a campaign against the move, said he was delighted by the MoD's change of plan.
A key part of the campaign had been help from the National Audit Office, which had been able to show the original figures on which the closure decision was based "were not sound".
He added that "the cost of rebuilding RAF Boulmer's facilities elsewhere would be colossal".
"RAF Boulmer is important in terms of our national defence but is also very significant in supporting our local economy and its loss would have had serious consequences for our area," said Mr Beith.
Defence Minister Bob Ainsworth said: "I'm pleased to announce that, after a thorough review of the options, RAF Boulmer will remain the Air Surveillance and Control System hub.
"This is great news for the military and civilian staff on site and the local community."