A longtime fixture atop US carriers, Parker led US Airways prior to its merger with American Airlines in 2013 when he took over the combined company. He will step down March 31 but remain chairman of the board.

American's leadership transition was delayed by the Covid-19 pandemic "and the devastating impact it had on our industry," Parker said in a letter to employees.

"While we still have work to do, the recovery from the pandemic is underway and now is the right time to make the transition," Parker said.

American entered the pandemic downturn with more debt than rivals, but has benefited from federal support programs, as well as ready access to public markets amid low interest rates.

Like other US carriers, American's financial position has improved over the last 18 months, as air travel has gradually ramped back up.

In the third quarter, American reported $169 million in profits after losing $3.1 billion in the year-ago period.

US carriers have seen a strong recovery in domestic leisure travel, but business travel remains depressed and international revenues are still well below pre-pandemic levels.

Isom, who also worked in leadership posts at US Airways prior to joining American, said he was "humbled" to take over the job, adding, "We are positioned to continue to lead the industry as travel rebounds."