A company in Hampshire that provides helicopter maintenance to the Ministry of Defence (MoD) is to be privatised in a £17m deal.
Lynx helicopters are among those repaired at Fleetlands
Union leaders have warned of strike action over the government's decision to sell the Defence Aviation Repair Agency (Dara) facility at Fleetlands.
The MoD said the sale to Canadian-owned Vector Aerospace will guarantee the future of 350 jobs.
A facility at Almondbank in Perthshire, Scotland, is also being sold off.
The Fleetlands facility, in Gosport, provides maintenance, repair and overhaul support for the MoD Chinook (CH-47), Lynx and Sea King helicopters.
Defence minister Baroness Taylor said: "In selling Dara we are confident that we are securing a long-term future for the business.
"This is the best result for defence, for our Armed Forces, and for the employees."
Vector Aerospace chairman Don Jackson said: "We are looking forward to growing the level of support that we are providing to the UK MoD and to working with the employees at Almondbank and Fleetlands to create a centre of excellence in European helicopter maintenance.
"We have expansion plans and hope to increase our staff numbers as appropriate."