When Air Canada pilots went on strike in September 1998 for 13 days, all of the carrier's more than 600 daily flights were grounded, stranding passengers and costing the airline C$133m ($96m; £71m) before a negotiated deal was reached.

Air Canada grounded most of its flights in response to a strike by its flight attendants. Here's what it means for airline passengers in the U.S.

The Montreal-based airline said labor negotiations with its 10,000 flight attendants are at an impasse and warned that the carrier may begin to shut down operations as early as Saturday without an agreement.