The Secretary of Transportation shall prescribe regulations on standards for installing navigational aids, including airport control towers. For each type of facility, the regulations shall consider at a minimum traffic density (number of aircraft operations without consideration of aircraft size), terrain and other obstacles to navigation, weather characteristics, passengers served, and potential aircraft operating efficiencies.
(Pub. L. 103–272, § 1(e), July 5, 1994, 108 Stat. 1201.)