Study: U.S. airlines will fly record number of passengers this summer

May 21 (UPI) -- More Americans will travel the skies this summer than ever before, an aviation trade group said in a study Tuesday.

Airlines for America said in new research it expects nearly 260 million travelers will fly U.S. airlines this summer -- a 3.4 percent increase over last summer, when 249 million flew. The increase marks the tenth consecutive summer U.S. carriers have seen an increase in summer passengers.

"With airlines offering low fares and reinvesting billions of dollars in their product, there's never been a better time to fly," Airlines for America Vice President John Heimlich said in a statement. "Air travel is the nation's safest form of transportation, and it is now more affordable than ever before."

The record number equates to an average of 2.8 million passengers per day between June 1 and August 31, and carriers are adding seats to accommodate the additional 93,000 daily passengers.

Three U.S. airlines will go into the busy summer season without its Boeing's 737 Max fleet. American, Southwest and United all fly the models, which have been grounded worldwide as investigators examine crashes of the Max 8 in Indonesia and Ethiopia.

American said it's had to cancel 90 flights daily through early June because of the grounding. Southwest has grounded 34 Max 8s and United 14 of its Max 9s, which are also affected by the safety precaution.

Further, American and Southwest have extended the grounding through August. United said its planes won't fly until at least July.

Investigators have said faulty sensor data appears to have played a role in the crashes, which killed more than 300 people. Boeing completed a software update last week, which is awaiting FAA approval.

"I do not know when the MAX will be returned to service, I am hopeful it will be this summer," Southwest CEO Gary Kelly said last week.