Tony Didoshak with the International Association of Machinists and Aerospace Workers said Aveos employees were given the notice simultaneously at 1:30 p.m. ET on Sunday in Montreal, Winnipeg and Vancouver.
The union, which also represents Air Canada's mechanics, baggage handlers and ramp personnel, had feared for Aveo's future after Air Canada moved to subcontract some of its work offshore.
"It is my understanding that Aveos has ceased operations," said Didoshak, who is the union's general chairman in Winnipeg.
Didoshak said union officials haven't been able to reach anyone with Aveos to confirm the layoffs. Attempts by The Canadian Press to reach the company were also unsuccessful.
Air Canada (TSX:AC.B) has moved maintenance of landing gear and engines out of Aveos facilities and is sub-contracting work to other maintenance providers, including to China. The airline has also delayed some work until the fall.
Aveos was once Air Canada's technical services division but was later spun off as a separate company. The airline is Aveos' largest customer, providing about 90 per cent of its maintenance overhaul work.
Its exclusive contract expires in June 2013 and Air Canada has issued a request for proposals for future contracts.
Fred Hospes, chairman of the IAWAW District 140 Western Region, said earlier this month that the union was seeking conciliation — a process involving federal officials — in a bid to get more details about the financial difficulties facing Aveos.
Didoshak said work slowed down about three weeks ago in Winnipeg where Aveos services Air Canada's Embraer 190 jets.
"We had aircraft that were supposed to show up that haven't been showing up," Didoshak said.
No one from Air Canada could be reached on Sunday evening to respond to how the Aveos plants shutdown would affect the airline, which is in the middle of a bitter labour dispute with its pilots.
On Sunday, the airline asked the Canada Industrial Relations Board to step in after an unusually high number of pilots called in sick over the weekend, causing some flights to be cancelled or delayed.
_ By Rob Drinkwater in Edmonton.
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