Long lineups at airports are nothing new, but the delays at major U.S. airports are becoming so extreme that Canadian airlines are beginning to take note.

WestJet has said it's considering sending its own staff  to help move along lengthy Transportation Security Administration (TSA) lines, as the hours-long wait to get through security is impacting Canadian travellers.

"We are concerned that long TSA lines this summer will impact the overall guest experience in the U.S.," the airline said in the statement to BNN. "WestJet is exploring the possibility of increasing airport staff to assist TSA lines in some of the key airports."

Air Canada, meanwhile, said it's monitoring the increased wait times and has been advising its customers to leave themselves more time when travelling via U.S. airports through their website and check-in email reminders.

The TSA and U.S. Congress cut the number of screeners on expectations that an expedited screening program called PreCheck would speed up the lines. However, not enough people have enrolled.

The TSA has experienced a drop in 10 per cent of screeners since 2013. Over that same period of time, air travel has increased 12 per cent. Air officials expect travel during the peak summer season to surpass 2015’s record numbers due to a stronger U.S. economy and cheaper airfare.

Last summer, 17 million Canadian passengers were screened at airports, according to the Canadian Air Transport Security Authority. And the agency is expecting to see an increase in travellers this summer.

Earlier this month, U.S. Congress agreed to move up US$34 million in TSA funding to hire 768 more screeners in the next month and pay overtime to existing employees. 

But some airports have already taken matters into their own hands.

BNN's Paige Ellis said 22 U.S. airports have hired their own private contracted screeners to help move long lineups along, and more airports are threatening to follow suit.

Air travellers in the U.S. are asked to allot themselves two hours to get through baggage check-in and security at major airports.

At Toronto Pearson International Airport, the busiest airport in the country, travellers heading to the U.S. are asked to arrive at least two-and-a-half hours ahead of their departure time. 

For the majority of U.S. flights, passengers leaving Pearson will go through U.S. customs at the Toronto airport.    

For its part, the TSA has asked airlines to stop charging for checked baggage, Ellis said, as the agency believes an increase in carry-on bags passengers are bringing onboard is adding to the wait times.