US is investigating Delta’s flight cancellations and faltering response to global tech outage [Video]

U.S. regulators are investigating why Delta Air Lines failed to recover as quickly as other airlines from a global technology breakdown and whether Delta’s treatment of passengers stranded by canceled and delayed flights violated federal rules.

Transportation Secretary Pete Buttigieg on Tuesday announced the investigation into Delta’s response to the outage, which he said has affected more than half a million of the airline’s passengers.

A Delta official said the airline expects to return to normal operations by the end of the week.

Delta and its Delta Connection partners canceled more than 500 flights Tuesday. That was down by more than half from Monday but still accounted for nearly two-thirds of all canceled flights in the United States, according to tracking platform FlightAware.

Many airlines were affected when cybersecurity company CrowdStrikesent a faulty update to more than 8 million Microsoft computers around the world late last week. Most of them reduced cancellations to roughly normal levels by …