Americans are flying again; here's how long until we see 1 million daily travelers

After hitting rock bottom in April, passenger traffic might be poised for a summer comeback as travelers increasingly take to the skies as coronavirus-related stay-at-home restrictions begin to ease across much of the nation.

The latest hint of a rebound came Sunday, when the Transportation Security Administration on Sunday screened more than 400,000 — the agency's highest total since March 22.

While the increase is a positive sign, it still comes with a catch. The 441,255 people who passed through TSA checkpoints on Sunday was just about 17% of what was normal, in pre-COVID times. For comparison, more than 2.6 million people went through airport security in the U.S. on the first Sunday in June 2019.

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Still, the trend has been an upward one for TSA screenings since a record low on April 14, when only 87,534 people visited the agency's checkpoints.

Read more: 3 ways the TSA experience will be different next time you fly.

Henry Harteveldt, president of travel analysis firm Atmosphere Research said that TSA screening numbers are likely to keep growing as the summer travel season gets underway.

Summer is by far the busiest season of the year for U.S. airlines. Underscoring that: eight of the TSA's 10 busiest days in 2019 came in June, July and August. A ninth came during the late May weekend surrounding Memorial Day, the holiday that's regarded as the unofficial kickoff to summer for many Americans.

This year, it's a near certainty that summer won't see the peak of 2.7 million daily passengers seen during the summer of 2019. But might TSA screenings hit the psychologically meaningful threshold of 1 million?

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It could happen, said Harteveldt, who predicted TSA screenings could top 1 million in the first half of July, and possibly by Independence Day, as loosening restrictions and peoples' desire to get out of the house accelerates travel demand.

"It’s possible that milestone may happen over the July 4 holiday if more communities, including their hotels, vacation rental properties, attractions, restaurants, entertainment venues, stores, etc. reopen," he said by email.

While it's true that traveler numbers are rebounding, Robert W. Mann, an aviation industry analyst based in the New York City suburbs, said it doesn't mean airlines are returning to their pre-pandemic state of financial health.

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"While the TSA screening volume is a near-realtime measure, it means very little compared with revenue," he said, noting that airlines are still hemorrhaging cash and slashing fares to try to lure travelers back on to their planes.

That, Mann added, suggests much of the passenger increases likely are "price-stimulated."

More: With over 90% of flyers still grounded, what it’s like flying in the U.S. right now

And as bargain fares may already be driving some of the passenger numbers, the upward trend could gain even more momentum as things reopen. New York, for example, just ended its stay-at-home orders, possibly enticing travelers from the nation's biggest city to fly again. And wherever travelers are coming from, there are increasingly more places to go. Popular leisure draws are slowly coming back online. Las Vegas' famed casinos are again welcoming guests. Theme parks — long a major driver of summer travel — also are reopening. That includes Florida's Universal Studios park, which reopened last week.

Still, Harteveldt pointed out that demand remains significantly suppressed as well. Even the TSA's screening total from this past Sunday is down more than 80% over the same date in 2019.

Even so, increasing TSA screening numbers indicate that airlines may be on the takeoff roll to recovery.

About Las Vegas: 7 photos and videos that show what Las Vegas looked like on reopening weekend

But, Mann cautioned the trend may not hold after the summer if corporate risk managers remain cautious about letting employees travel for business.

"Come September, post-Labor Day, however, if higher frequency/higher fare corporate demand has not returned, based in part on good word of mouth from leisure traveler 'canaries in the coal mine', this fall's 'seasonal capacity adjustments' will be historic, and not in a good way," he said.