(Bloomberg) -- U.S. airlines are rushing to apply for federal aid as their revenue plummets amid an unprecedented collapse in travel demand caused by the coronavirus pandemic.

Second-quarter sales will plunge 90%, Delta Air Lines Inc. said, and the carrier is burning through $60 million a day. JetBlue Airways Corp. expects to carry 7,000 passengers a day this month and probably in May, down from the typical level of 120,000. Both companies applied for government aid ahead of a Friday deadline, as did United Airlines Holdings Inc. and American Airlines Group Inc.

The government is supporting passenger carriers with cash assistance of $25 billion to help make payroll, plus another $25 billion in loans. But as passengers stay home, the companies said they would be forced to do more to reduce costs by parking jetliners, asking employees to take voluntary leave and cutting executive salaries.

“We appreciate the decisive action of our nation’s leaders to protect our people. But those funds alone are not nearly enough,” Delta Chief Executive Officer Ed Bastian said in a memo to employees. “Without the self-help actions we are taking to save costs and raise new financing, that money would be gone by June.”

Alaska Air Group Inc., the nation’s fifth-largest airline, also intends to apply for government help, as does Southwest Airlines Co.

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