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The surge in overtime shows a split among U.S. carriers. Delta has had to scramble to meet demand while staff at Southwest Airlines and American Airlines are sitting at home collecting basic pay.
It has also strained the airline's labor costs, in part because more flights needed to be added, according to Reuters.
|DAL||DELTA AIR LINES INC.||53.37||+0.20||+0.38%|
According to a unit of the Air Line Pilots Association, Delta pilots filed for record overtime between May and August, double that of the same period a year ago.
Last week, Delta raised its third-quarter growth cost forecast per available seat mile due to a boost in employee wages.
Overall capacity growth is expected to outpace rivals, although the carrier is downplaying the 737 Max grounding as a factor.
The Boeing 737 Max was grounded worldwide in March following two crashes that killed 346 people.