Air rights

To promote air transport, legislators established a public easement for transit at high altitudes, regardless of real estate ownership.

In the United States, the Federal Aviation Administration (FAA) has the sole authority to regulate all "navigable airspace" exclusively determining the rules and requirements for its use.

[7] This is especially important as some aircraft (crewed and uncrewed) now have no minimum flight altitudes making virtually all airspace "navigable".

[12] There has never been a direct challenge to the federal government's vesting of the right for citizens to travel through navigable airspace.

This can include overhanging trees or signage from a neighbouring property, or movement such as a crane swinging overhead.

By 1954, the railroad began to realize it could sell more air rights and Grand Central Terminal was proposed to be replaced by a 50-story tower.

This is how the MetLife Building came to be built next to the station, after public protest regarding the demolition of Grand Central Terminal.

In the mid-2000s, New York's Metropolitan Transportation Authority (MTA) attempted to sell air rights to the New York Jets so that they could build the West Side Stadium over Manhattan's West Side Yard, near Penn Station, as part of the Hudson Yards Redevelopment.

[citation needed] Similar to railroads, builders of highways have proposed selling their air rights; Boston did this in connection with the Big Dig.

[22] The city of Los Angeles funded a $100,000 feasibility study RFP in January 2007 to explore building a freeway cap park in Hollywood.