If Delta Air Lines were to shut its doors, it could take Atlanta’s airport up to five years to recover, according to airline industry observers.

With Delta’s pilots threatening to strike within the next few weeks, some in the industry have begun to think the unthinkable. Delta filed for Chapter 11 bankruptcy protection in September. The airline and its pilots went before an arbitration panel on March 13 after the two sides were unable to reach an agreement on pilot wage cuts.