Aer Lingus plans to hire more than 20 aircraft this Thursday and again on Monday in an attempt to prevent widespread disruption to thousands of passengers.
More than 20,000 passengers are booked to fly with the airline on Thursday but strike action by cabin crew could jeopardise the 200 scheduled flights, of which 26 have been cancelled.
The cabin crew are members of Impact and are objecting to new roster arrangements. The union is also threatening to take strike action this Bank Holiday Monday when more than 20,000 passengers are due to travel.
The hiring of more than 20 aircraft from other airlines around Europe could escalate the dispute, but a spokesman said last night that the company was determined passengers would only face very limited disruption.
The hiring of the aircraft could be very costly, with a likely charge of up to €500,000 for Thursday alone. Aer Lingus has previously hired aircraft from charter carrier Futura Air and the Spanish carrier Spanair.
Mr Shay Coady, of Impact, said a Labour Court recommendation was expected this week, and the union's executive would study it closely. If it was positive a fresh ballot might have to be held.
Meanwhile, Aer Rianta unions, who served two weeks' strike notice have threatened strike action beginning on November 4th with a two-hour stoppage. The unions say rolling industrial action is likely if the Minister for Transport, Mr Brennan, does not agree to talks under an independent chairman.
Mr Brennan has rejected trade union demands to abandon his plan to break up the three Aer Rianta airports. Mr Brennan's spokesman said the plan had been endorsed by the Government, and was not open to review.