FORT WORTH, Texas — A letter sent to employees of Fort Worth-based American Airlines Wednesday warns another round of furloughs is anticipated and could involve roughly 13,000 workers.

It’s stated employees will receive notices on Friday, but that doesn’t automatically mean they will be laid off. Federal payroll aid is set to expire on April 1, but there are efforts underway by airline unions to obtain another $15 billion in aid, which would keep the industry aloft until roughly October.

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According to the letter, American Airlines management anticipated COVID-19 vaccines would be distributed more quickly, potentially leading to a more robust summer travel forecast. That has not turned out to be the case.

In fact, the letter states, air travel is down in the first quarter about 45% from what it was during the same period in 2019.

The company says it will offer a voluntary early out program as well as a long-term leave-of-absence program for frontline members, not including pilots.

Competitor United Airlines last week notified roughly 14,000 employees of impending furloughs.

According to Forbes, American Airlines employs approximately 133,700 people.