As many as 180 jobs could be under threat at RAF Valley if a contract is moved to another base, a union fears.
Unite is “deeply concerned” by plans which could see workers cut from the Hawk contract, servicing T1 and T2 jets.
It was “astounded” at the proposals and “deeply concerned” the motive was political.
The Ministry of Defence (MoD) and BAE Systems said they are committed to ongoing dialogue with employees.
Unite said the plans would see work on the T1 moved to RAF Leeming in North Yorkshire, which could lead to the loss of an initial 50-70 maintenance jobs at RAF Valley.
“In relation to the T2 Hawk there is a threat of greater job losses in the proposal, which could see a further over 100 jobs lost by 2033 based on the figures supplied to Unite,” said a spokesman.
‘Wrong time, wrong reasons’
Chancellor Rishi Sunak, who is the MP for the Richmond area of Yorkshire, has championed bringing work to RAF Leeming and had hoped the Red Arrows would move there.
Peter Hughes, Unite regional secretary, said the rationale for moving the T1 Hawk work to RAF Leeming “does not add up.”
“We believe these are the wrong proposals at the wrong time and for the wrong reasons,” Mr Hughes said.
“The MoD should be investing in the RAF Valley workforce for the long term rather than looking to cut jobs.”
The MoD said it was in discussion with BAE Systems as part of “routine business” to determine potential future support options for the Hawk.
“Both the MoD and BAES remain committed to ongoing dialogue with our employees and their representatives,” a spokesman said.
A BAE Systems spokesman said: “We are committed to ongoing dialogue with our employee representatives about the future delivery of support to the Hawk fleet.”