A pilot speaks on a mobile device near a Delta Air Lines gate at Salt Lake City International Airport.

George Frey | Bloomberg | Getty Images

Delta Air Lines announced on Wednesday that it will resume hiring new pilots after other airlines prepare for future staff as the demand for travel picks up again.

The Atlanta-based airline will initially add 75 pilots with conditional vacancies “and likely to increase the number of new pilots by September,” wrote John Laughter, Delta senior vice president and chief of operations, in a staff memo, that was seen by CNBC.

United Airlines, American Airlines, Spirit Airlines, and JetBlue Airways have either resumed hiring pilots or are planning for this year.

Airlines expanded jobs to hundreds of pilots over the past year, but the Covid-19 pandemic has halted their training. The airlines then offered the pilots and other staff an early retirement and temporary paid vacation to reduce the number of staff as the demand for travel fell.

Now airlines are looking to add new pilots as hundreds of their current pilots near the federal retirement age of 65.