(CNN) The first round of relief for airlines rocked by coronavirus turbulence is not arriving as a bailout check, but as a regulatory waiver that will help them dramatically trim their flight schedules without a substantial penalty.

The Federal Aviation Administration waiver issued Wednesday was a key ask of the airlines, which, two sources familiar with the industry told CNN, have not yet asked for federal funding to help their bottom lines, even while forecasting many rough months ahead as demand for air travel plummets.

Prior to the waiver, airlines faced the difficult choice of operating near-empty -- and money-losing -- flights or cancelling those flights and losing their share of the limited takeoff and landing opportunities at some of the nation's busiest airports, according to Nick Calio, president of the trade group Airlines for America.

Under the now-suspended rule, each airline had specific, short windows during the day to use the congested runways at airports like New York's LaGuardia Airport and Reagan National Airport outside the nation's capital. If an airline did not take off or land a plane at least 80% of the time during that window, the slot could be given to another airline.

"By putting the use-or-lose slot rules on hold, the FAA and the EU are telling airlines they can go ahead and do what they have to in order to align their business with demand in the short term," said Helene Becker, an aviation analyst at Cowen.

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