Airlines add summer flights as industry begins slow recovery

Airlines are adding flights to their summer schedules as the number of people flying continues to steadily increase -- the first signs that demand for air travel is beginning to recover after reaching historic lows amid the COVID-19 pandemic.

American Airlines announced Thursday that it is increasing domestic flights in July after seeing the number of average passengers per day jump from around 32,000 in April to 110,000 during the last week of May.

"April was a disaster for aviation as air travel almost entirely stopped," International Air Transport Association Director General and CEO Alexandre de Juniac said. "But April may also represent the nadir of the crisis."

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An American Airlines spokesperson told ABC News that the airline's current demand estimates for July exceed the estimates that they previously had at the "bottom of the curve."

Airline shares were up considerably on Thursday following American's announcement.

Delta CEO Ed Bastian on Wednesday said Delta is planning to fly twice as many domestic flights in July than it did in May.

United Airlines has said it is planning to resume a quarter of its flights in July.

This comes as Transportation Security Administration (TSA) checkpoint travel numbers continue to slowly increase. Sunday marked the first time more than 350,000 people passed through U.S. airports since late March. However, compared with this time last year passenger volumes are still down 88% and airlines are expecting a long and sluggish road to recovery.

An American spokesperson said even if demand comes back this summer in a "meaningful way," the company is still expecting it to be "significantly lower than before the pandemic."

It took three years for passenger volumes to recover after 9/11 and over seven years to recover from the 2008 financial crisis, according to Airlines for America (A4A), an industry trade organization representing the major U.S. airlines.

"History has shown that air transport demand has never experienced a V-shaped recovery from a downturn," A4A said.

Carriers have implemented a wide range of policies aimed at reassuring travelers that flying is safe including mandatory masks, plexiglass barriers, touchless kiosks, high-tech aircraft cleaning and social distance friendly seating arrangements.

While Department of Transportation Secretary Elaine Chao said in a Politico interview Wednesday “I believe it is safe to travel," the Centers for Disease Control and Prevention still warns that "travel increases your chances of getting and spreading COVID-19."

Despite positive signs for the airline industry, all major U.S. airlines have announced that they are preparing for potential layoffs in the fall after they are no longer tied to the conditions set forth by Congress to receive federal assistance.

ABC News' Sam Sweeney and Amanda Maile contributed to this report.

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