The summer travel season is poised to inflict pain on both U.S. airlines and fliers.

A record 257 million people are expected to fly with U.S. airlines this summer, according to trade group Airlines for America. Those travelers will likely have to deal with the fallout from multiple challenges weighing on the nation’s air travel network, including the extended grounding of Boeing Co.’s 737 MAX jets, runway closures and labor shortages. Anticipating major logistical hurdles, airlines are rushing to make alternate arrangements.

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