Pilots training the military to fly helicopters in Iraq have voted overwhelmingly for strike action.
The 45 civilian trainers, based at RAF Shawbury, in Shropshire, are protesting at what they consider to be a two-tier wage system.
It will be the first-ever strike by pilots on a military base in the UK.
The British Airline Pilots' Association (BALPA) said that since the privatisation of pilot training, civilian pilots earn less than their RAF counterparts.
Its members at Shawbury voted overwhelmingly for the action, with 94 per cent backing a strike.
A further eight trainers based at RAF Valley in Anglesey, North Wales, are also being balloted.
The 53 trainers are employed by FB Heliservices and train 350 military pilots every year.
Jim McAuslan, general secretary of BALPA, said: "This is a tier workforce with pay levels about £7,000 lower than the pay of RAF pilot trainers doing exactly the same job. The remarkably high poll shows that our members are resolute in their aim to secure a satisfactory solution."
BALPA said salary levels for civilian trainers were between £29,000 and £40,000 per year.
Mr McAuslan added: "It is totally unfair and BALPA's claim is for an increase of 15 per cent spread over three years - five per cent per year. The company, which of course won the contract with their bid based on lower rates, refuses to agree."
He added the firm had offered an increase of ten per cent over three years but members rejected it.