49 U.S.C. § 44719 - U.S. Code - Unannotated Title 49. Transportation § 44719. Standards for navigational aids

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.