Search and rescue services (SAR) at HMS Gannet in Prestwick will be transferred to Glasgow Airport, it has been confirmed.
A private consortium, Soteria, has been appointed to take over SAR operations from 2012.
The consortium, which includes Royal Bank of Scotland, said the move would be made for commercial reasons.
It said the final decision considered factors such as local weather, 24-hour cover and maintenance facilities.
Soteria said the transfer would not lead to any job losses, although 26 military staff and 78 civilians work at HMS Gannet.
The new service run by the consortium will combine the current work of the RAF, navy and coastguard.
The current operation provides a 24-hour military and civilian search and rescue across a large area of Scotland, Northern England and Northern Ireland.
It operates three Sea King Mk 5 helicopters.
Confirmation of the decision follows a four-month campaign by local politicians, led by Labour MP for Central Ayrshire, Brian Donohoe, to halt the move.
Mr Donohoe said he was "extremely disappointed" by Soteria's decision.