What prevents a government from selling/leasing publicly owned airports? When an airport is open to the public, it is generally owned and operated by a government entity. If the local government leases or sells the airport, this would generate significant amounts of revenue.

What are the legal impediments which discourage a local government (who owns a public airport) from leasing or selling their airport to a private entity?
One possible impediment might be the grant assurances that come with accepting Federal aid to improve the airport.

In short, if the local airport accepts money from the Federal government to improve the airport, that money is often granted "with strings attached" - requirements that the airport remain open, etc.