Ryanair passengers face a renewed threat of disruption after Dublin-based pilots voted overwhelmingly to back industrial action in a dispute over collective bargaining and negotiating rights.
The move comes amid a dispute between the airline and its pilots who have rejected the company's collective bargaining structures.
The pilots believe these structures weaken the negotiating and bargaining power of employees.
They want to negotiate via their new collective European Employee Representative Council, rather than via individual Employee Representative Councils at each of the airline's 87 bases.
It is understood that the ballot carried out by the Irish Air Line Pilots Association - which is affiliated to IMPACT - covered only direct employees, rather than the significant number of contractor pilots hired through agencies, or through individual companies.
However, most of the directly employed pilots are captains, without whom planes cannot fly.
IMPACT confirmed that 84 ballot papers were issued to directly employed pilots and 83 were returned. One of those ballot papers was spoilt.
Of the remaining 82, 79 voted in favour of industrial action, with three against.
Ryanair has more than 300 pilots at its Dublin base.
The airline's pilots in Italy have already served notice of a four-hour stoppage this Friday, while Portuguese pilots have voted in favour of strike action, but have not yet served notice of any specific industrial action.
Meanwhile, Ryanair summoned its Dublin-based pilots to a meeting at its headquarters this evening.
In a statement this afternoon, Ryanair it said it had received "no notification of any industrial action by its Dublin pilots so we suspect this is more PR activity by Aer Lingus pilots group IALPA, to distract from their failure in negotiating a paltry 3% pay increase for Aer Lingus pilots.
"Now that Ryanair's Cork, Shannon and Belfast bases have agreed 20% pay increases we expect the Dublin pilots to follow this trend.
"However, if Ryanair's Dublin pilots are misled by some Aer Lingus pilots into industrial action then they will lose their favourable rosters (5on/4off, a double bank holiday every week) and remuneration benefits that are specifically linked by agreement to dealing directly with Ryanair.
"This might be the first time in Irish history that a few Aer Lingus pilots persuade Ryanair pilots earning between €150,000 to €180,000 to take up industrial action instead of a 20% pay increase when Aer Lingus pilots are only getting 3%.
"If any such industrial action occurs Ryanair will still not engage with, or recognise, Aer Lingus pilots or their IALPA union."
In a memo to pilots last week, the airline's Chief People Officer Eddie Wilson reiterated that the company would never negotiate with unions or the EERC, as its existing ERC system was validated by the Supreme Court in a 2007 case.
He warned pilots that if they did not negotiate locally through ERCs, pay rises and other benefits awarded recently would be withdrawn.
He also warned that the Dublin base would be "frozen" until further notice with no promotions for First Officers or Second Officers, and no transfers facilitated out of the base.
In addition, the 5/4 roster, the recent €10,000 base allowance and other annual allowances would cease immediately.
Mr Wilson also warned that the airline may in due course be forced to look at transferring some Dublin aircraft to lower cost airports elsewhere in Europe where pilots continue to deal directly with management.