pilots approved a sweetened labor deal, making the carrier the second major U.S. airline to seal a new contract with its highest-paid work group.

The more than 15,000 pilots at American will get immediate raises of 21% with compensation increasing more than 46% over the duration of the four-year contract, including 401(k) contributions, their union said Monday. They will be due a 5% raise next year, followed by 4% in 2025 and 2026, followed by a 3% increase in 2027.

Pilots have been pressing airlines for better compensation and work rules as the industry faces a shortage of aviators in the wake of the Covid pandemic. That crisis derailed negotiations, preventing many workers across the airline industry from getting contracted pay increases, while .

An earlier deal between American and the union fell apart after rival and that carrier's union reached a richer, preliminary deal. But American its offer last month.

American's pilots voted more than 72% in favor of the new contract, and there was a 95% turnout, according to the Allied Pilots Association. The agreement also includes improvements in scheduling and benefits.

American said on Tuesday retroactive pay for the pilots will cost it $230 million in the third quarter. The airline raised its unit cost guidance on Tuesday to a 4% to 6% increase compared with the same period last year, up from a previous forecast of a 2% to 4% increase, maintaining its annual guidance.

"This agreement will help American immediately expand our pilot training capacity to support under-utilized aircraft and future flying and provide our pilots with more opportunities to progress in their careers," American's CEO, Robert Isom, said in a statement.

pilots ratified a new agreement earlier this year.