VOR

From HFUnderground

VHF Omnidirectional Radio Range or "Omni Range"

Very High Frequency Omnidirectional Radio Range - VHF aircraft band radio navigation system. Widely used, generally replaced (or at least supplanted non-directional beacons (NDBs). Now VOR is being generally replaced (or largely supplanted by) GPS or GNSS systems - otherwise referred to as SATNAV or RNAV. The ILS service remains in operation worldwide, as does the VOR services, VORTAC and VOR/DME services.

Fixed service, 108 MHz to 117.95 MHz, worldwide. The 108-118 portion is often referred to as the "nav" band (see also: ILS, DME).

The ILS service uses frequencies in the 108.1 MHz - 111.95 MHz VHF band (localizer - which provides horizontal guidance - that is - if the aircraft is to the right of the runway centerline, to the left of the runway centerline or right in the middle) and a paired frequency in the 328.6 MHz - 335.4 MHz UHF band (glideslope or glide path - which provides vertical guidance - if the aircraft is too high, too low or right "on the beam" or "on the glideslope" to come down to the foot of the runway). See the ILS page for more information.

The VOR system also operates in the 108 MHz - 112 MHz band and the 112.05 MHz - 117.95 MHz band (50 kHz spacing in the 112.050 MHz - 117.950 MHz band).

Since the 108-112 MHz section is shared between the VOR, VOR/DME, VORTAC navigational stations and the ILS service, care must be taken to avoid accidentally tuning into a VOR and trying to use it as an ILS. No, seriously, airplanes have crashed because pilots tuned to a VOR and treated it like a ILS.

All of these services are considered radionavigation or radiodetermination services under the fixed service.

They operate as aircraft radio navigation beacons and permit navigation in poor weather or at night. Development of these various systems dates back to the 1920s and 1930s, with the development of the low frequency radio range (LFRR) - referred to as just the range, the VHF low band Lorez blind landing beam system or "Lorenz Beam" (which operated in the 30-33 MHz band) and other similar systems.

The onset of World War II spurred the development of radar as well as numerous short-range and long-range radio navigation beacon and beam systems for bombing, including hyperbolic navigation (the beginnings of what would become the LORAN and LORAN-C systems), single-beacon and transponder based systems (which functioned the same way as the modern DME system), blind landing systems, etc. The "Battle of the Beams" focused mainly on the RAF and the Luftwaffe developing competing systems and countermeasures for those systems.

The frequency 108.0 MHz may be used for testing purposes only, due to the potential from FM broadcast band interference from FM stations operating on 107.9 MHz. 108.000 MHz may not be used for navigation purposes.

VOR frequencies (full list)

• 108.2 MHz
• 108.25 MHz
• 108.4 MHz
• 108.45 MHz
• 108.6 MHz
• 108.65 MHz
• 108.8 MHz
• 108.85 MHz
• 109.0 MHz
• 109.05 MHz
• 109.25 MHz
• 109.4 MHz
• 109.45 MHz
• 109.6 MHz
• 109.65 MHz
• 109.8 MHz
• 109.85 MHz
• 110.0 MHz
• 110.05 MHz
• 110.25 MHz
• 110.4 MHz
• 110.45 MHz
• 110.6 MHz
• 110.65 MHz
• 110.8 MHz
• 110.85 MHz
• 111.0 MHz
• 111.05 MHz
• 111.2 MHz
• 111.25 MHz
• 111.4 MHz
• 111.45 MHz
• 111.6 MHz
• 111.65 MHz
• 111.8 MHz
• 111.85 MHz
• 112.0 MHz
• 112.05 MHz
• 112.1 MHz
• 112.15 MHz
• 112.2 MHz
• 112.25 MHz
• 112.3 MHz
• 112.35 MHz
• 112.4 MHz
• 112.45 MHz
• 112.5 MHz
• 112.55 MHz
• 112.6 MHz
• 112.65 MHz
• 112.7 MHz
• 112.75 MHz
• 112.8 MHz
• 112.85 MHz
• 112.9 MHz
• 112.95 MHz
• 113.0 MHz
• 113.05 MHz
• 113.1 MHz
• 113.15 MHz
• 113.2 MHz
• 113.25 MHz
• 113.3 MHz
• 113.35 MHz
• 113.4 MHz
• 113.45 MHz
• 113.5 MHz
• 113.55 MHz
• 113.6 MHz
• 113.65 MHz
• 113.7 MHz
• 113.75 MHz
• 113.8 MHz
• 113.85 MHz
• 113.9 MHz
• 113.95 MHz
• 114.0 MHz
• 114.05 MHz
• 114.1 MHz
• 114.15 MHz
• 114.2 MHz
• 114.25 MHz
• 114.3 MHz
• 114.35 MHz
• 114.4 MHz
• 114.45 MHz
• 114.5 MHz
• 114.55 MHz
• 114.6 MHz
• 114.65 MHz
• 114.7 MHz
• 114.75 MHz
• 114.8 MHz
• 114.85 MHz
• 114.9 MHz
• 114.95 MHz
• 115.0 MHz
• 115.05 MHz
• 115.1 MHz
• 115.15 MHz
• 115.2 MHz
• 115.25 MHz
• 115.3 MHz
• 115.35 MHz
• 115.4 MHz
• 115.45 MHz
• 115.5 MHz
• 115.55 MHz
• 115.6 MHz
• 115.65 MHz
• 115.7 MHz
• 115.75 MHz
• 115.8 MHz
• 115.85 MHz
• 115.9 MHz
• 115.95 MHz
• 116.0 MHz
• 116.05 MHz
• 116.1 MHz
• 116.15 MHz
• 116.2 MHz
• 116.25 MHz
• 116.3 MHz
• 116.35 MHz
• 116.4 MHz
• 116.45 MHz
• 116.5 MHz
• 116.55 MHz
• 116.6 MHz
• 116.65 MHz
• 116.7 MHz
• 116.75 MHz
• 116.8 MHz
• 116.85 MHz
• 116.9 MHz
• 116.95 MHz
• 117.0 MHz
• 117.05 MHz
• 117.1 MHz
• 117.15 MHz
• 117.2 MHz
• 117.25 MHz
• 117.3 MHz
• 117.35 MHz
• 117.4 MHz
• 117.45 MHz
• 117.5 MHz
• 117.55 MHz
• 117.6 MHz
• 117.65 MHz
• 117.7 MHz
• 117.75 MHz
• 117.8 MHz
• 117.85 MHz
• 117.9 MHz
• 117.95 MHz