Definition
The radio frequency band from 300 megahertz (MHz) to 3,000 MHz (3 gigahertz). In aviation, UHF is used primarily by military aircraft for air-to-air and air-to-ground voice communications, and by certain navigation aids such as the glideslope portion of the Instrument Landing System (ILS) and Distance Measuring Equipment (DME).
Plain English
A range of radio frequencies higher than the ones civilian pilots normally talk on. Military pilots use it for voice, and some navigation equipment uses it too.
Context Anchor
Seen in frequency listings, airport and ATC facility information, and communications involving military aircraft.
Derivation
‘Ultra’ comes from Latin meaning ‘beyond,’ and ‘high frequency’ refers to where these waves sit on the radio spectrum. So ‘ultrahigh frequency’ literally means ‘beyond the high-frequency band’ — the next step up.
Why Pilots Care
UHF provides dependable short-range communications, especially with military air traffic control and in situations where VHF is unavailable.
Intuition Check
Do not assume UHF is just a fancy name for any aviation radio frequency. It names a specific radio-frequency range, and the aircraft must have equipment that can use it.
Example Sentence 1
The glideslope portion of the ILS transmits on a UHF frequency, while the localizer transmits on VHF.
Example Sentence 2
Many military aircraft monitor the UHF emergency frequency of 243.0 MHz during training flights.