Salaries for new cabin crew also cut.
SIPTU says it'll be engaging with Aer Lingus next week, after the airline announced plans for a pay freeze for workers until 2026.
New cabin crew staff's pay would start on around 23 thousand euro, a drop from almost 26 thousand, under the proposals.
Staff pension contributions would fall from 10 to 7 per cent for those hired in the future and sick pay would be cut from 26 weeks full pay to 13 weeks.
SIPTU Aviation Sector Organiser Neil McGowan says a pay freeze lasting 5 years is unacceptable:
Neil McGowan says the union's going to meet the airline soon to discuss the proposals: