In a separate notice last week, regional carrier American Eagle warned that 146 employees at Miami International Airport could be affected, including 77 pilots and 65 flight attendants. Parent company AMR had wanted to sell or spin off its smaller Eagle operation, but those plans have been on hold since the November bankruptcy filing.

Part of the airline’s overall strategy for post-bankruptcy success is to increase traffic at key hubs by 20 percent over the next five years. American has emphasized that Miami, with its profitable Latin American routes, is critically important to American.

On Tuesday, an airline spokeswoman said that growth is happening already. Through August, the number of available seats flying to and from Miami has increased by 4.6 percent year-over-year and passenger numbers are up 6.1 percent compared to the same time in 2011.

American is by far the largest carrier at Miami International Airport — and the airport said it does not expect that to change with layoffs.

“While this action represents an undetermined decrease in jobs and local employees likely being replaced, and the County is certainly saddened by any potential job loss, American Airlines has assured us that it remains committed to expanding operations at Miami International Airport as one of its most profitable hubs,” said Greg Chin, spokesman for the Miami-Dade Aviation Department. “The company has also assured us it will provide assistance to employees who are replaced or laid off with job placement tools.”

The airline said previously that it intends to outsource some jobs, such as cargo agents and maintenance workers, but plans to help displaced employees get new jobs with contracting companies.

Michael Boyd, an aviation consultant in Evergreen, Colo., said outsourcing makes sense as AMR tries to appease creditors by cutting payroll. But cut too deep, and American risks tarnishing its standing with passengers, he said.

“An airline is a service organization. You can’t just outsource everything,” Boyd said.

While agreements with several labor groups have helped to reduce the number of layoffs that will be necessary, pilots voted overwhelmingly against the company’s last contract offer, and a federal bankruptcy judge allowed American to impose new pay and working rules on pilots.

The Allied Pilots Association has asked federal officials to approve steps that could eventually lead to a strike, but permission hasn’t been granted.

Still, pilots are holding a strike-authorization vote. And according to the company, in recent days they have called in sick more often than usual, contributing to an increase in canceled flights. American has trimmed its September and October schedule by up to 2 percent to make sure it has enough pilots to operate flights.

Hunter Keay, an analyst for Wolfe Trahan & Co., said the threat of cancelations won’t cause travelers to avoid American. But he said there has been “a clear deterioration in labor relations” at American.

Keay said that an American merger with US Airways Group Inc. could produce a bigger airline with more revenue and more labor peace. The two companies announced on Aug. 31 that they would start talks to discuss a potential merger.

Miami Herald staff writer Douglas Hanks contributed to this report, which was supplemented with information from the Associated Press.