Business travellers face further possible misery as unions PCS, Unite and Prospect announce they are to ballot members on industrial action over a pay dispute with airport operator BAA.
Prospect and Unite will open the ballot on July 23 and close on August 12.
Members of the unions based at Heathrow, Edinburgh, Glasgow, Southampton and Stansted airports will be balloted.
According to Ben Middleton, a Prospect negotiator, BAA staff accepted a pay freeze in 2009 "to assist the company during a difficult period".
He said that BAA has "let its workforce down badly" and members were "outraged" by BAA's decision not to honour a £450 one-off payment agreed as part of the 2009 deal and an expected airport bonus normally paid within the summer period.
"Their loyalty to the company has not been recognised by management which has shown a complete disregard for the important contribution its employees make to the continued success of the business," said Middleton.
"BAA has also chosen to ignore warnings from the negotiating table that their actions were confrontational and invited a reaction from staff."
A previous "consultative" ballot was held on a pay offer from BAA, which was rejected by 90% of voters.
This offer was for a 1% increase in basic salary, with a further 0.5% linked to a new attendance management policy.
Brendan Gold, Unite's national officer for civil aviation, said: "Unite and BAA have been in talks for months and we are prepared to continue talking. A negotiated agreement can be reached if the company is prepared to be fairer and more realistic.
"BAA missed its earnings target by a tiny three per cent and the company has still refused to give its staff any financial recognition for coming so close. The union understands the difficulties the airline industry is facing but BAA must realise that these airport workers are struggling to make ends meet."
PCS, which represents around 400 staff across BAA airports, will also be balloting its members, on industrial action "short of a strike", which would mean steps such as a ban on overtime and "withdrawal of goodwill".
A BAA spokesperson said the company is "disappointed" at the decision to ballot on strike action, and it believes the offer of a conditional 1.5% pay rise is "reasonable... at a time when BAA and its airline customers are seeing a decline in passengers due to the impacts of recession and volcanic ash."
"We regret Unite's decision, which will cause unnecessary concern for millions of our passengers and damage Britain's reputation around the world," the spokesperson added.