Plain English Meaning

Two ranges of radio waves used in flying. VHF is the range most civilian pilots talk on and use for many navigation signals. UHF is a higher range used mostly by the military and for some parts of instrument approach systems. Both only work when the aircraft has a clear straight path to the ground station.

Full Definition

Two adjacent bands of the radio frequency spectrum used in aviation. VHF covers 30 to 300 megahertz (MHz) and is used for civil air-to-ground voice communication (118.000–136.975 MHz) and for navigation aids such as VOR and localizers. UHF covers 300 to 3,000 MHz and is used primarily for military air-to-ground voice communication and for components such as the portion of an ILS and . Both bands are , meaning the signal travels in a straight line and is generally by or the curvature of the Earth.