CALGARY — Air Canada and WestJet are facing a potential class action lawsuit after imposing checked baggage fees only days apart.

The proposed class action alleges that the two airlines colluded to impose the fees and have unjustly enriched themselves in the process.

“I just thought it was so wrong, what the airline companies were doing,” said Lorne Hodel, lead plaintiff of the lawsuit.

The statement of claim, filed in the Court of Queen’s Bench for Saskatchewan, says WestJet (TSX:WJA) announced a $25 baggage fee on Sept. 15, 2014, and Air Canada (TSX:AC) followed suit on Sept. 18.

The claim alleges it would have been “impossible” for Air Canada to be ready to implement the fees only days after WestJet, indicating collusion between the airlines.

Tony Merchant, the class action lawyer who filed the claim, said it was also suspicious that Air Canada announced the same fee structure as WestJet, with both adding a $25 fee for a first checked bag for economy passengers in Canada.

“A coincidence we believe a court will find is highly suspicious, and not believably coincidental,” said Merchant.

In its 2014 announcement, WestJet said it would also start charging for first checked bags on flights to the U.S. Air Canada added Mexico and the Caribbean as destinations where passengers have to pay for a first bag.

Air Canada began charging economy passengers fees for their first checked bag on flights to the U.S. in 2011.

Merchant said the airlines charged more, without providing extra services.

“What new did I get for the extra 25 dollars? Well I got nothing new for the 25 dollars. That’s known as unjust enrichment,” said Merchant.

Air Canada and WestJet declined to comment because the matter is before the courts.

Karl Moore, an aviation expert at McGill University’s Desautels Faculty of Management, found the collusion allegations far fetched.

“I think it’s highly unlikely they would collude, it’s not the nature of the beast, they’re just fierce competitors,” Moore said.

He said both airlines had already been thinking about adding the baggage fees and WestJet’s move made it easier for Air Canada to add the fee as well.

“Both were thinking about it,” said Moore. “This was on their radar because it was happening elsewhere.”

He said the baggage fees are part of a wider trend of unbundling fees on airlines.

“You pay more for meals, you pay more for the seat you want, you pay for bags. They’ve unbundled, and this is just part of that unbundling process,” said Moore.

The proposed class action, which has yet to be certified, seeks to have baggage fees refunded along with other damages.

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