A spokeswoman for the Canadian Auto Workers Local 2002, which represents about 4,000 staff at Canada's largest airline, said the union may work to rule in protest, and did not rule out a strike.
The membership are so angry at the company's disrespectful approach to final and binding arbitration, said spokeswoman Delia Gaskill. We're going to do whatever it takes. Our members are ready.
Gaskill said a strike would be a last approach, but that the union is consulting with its lawyers, and considering every option.
The union walked out for several days in June over pensions for new hires. Under threat of government back-to-work legislation, the two sides agreed to send the issue to arbitration.
In September an arbitration panel selected the union's proposal for a hybrid defined-benefit and defined-contribution pension for new hires. Air Canada appealed that decision last Monday.
The union has characterized the appeal as a violation of the collective agreement.
Air Canada spokesman Peter Fitzpatrick said in a statement that the appeal did not violate the agreement.
Judicial reviews of arbitration awards are an established option and in this particular case we have concerns that (the arbitrator) may have acted beyond his jurisdiction, he said.