MONTREAL, Jan 25 - WestJet Airlines, Canada's No. 2 carrier, is experiencing delayed and canceled flights and expects 'further delays and possible cancellations if more constraints are placed' on the U.S. air traffic system, a spokeswoman said on Friday. Hundreds of flights were grounded or delayed at New York-area and Philadelphia airports as more air traffic controllers called in sick on Friday, in one of the most tangible signs yet of disruption from a 35-day partial shutdown of the U.S. government. 'We are responding to the situation as required to keep our guests moving,' said WestJet spokeswoman Lauren Stewart by email.
