VHF omnidirectional range
The VAR bridged the technological gap between the Low-Frequency Radio Range (LFR) radio navigation system and the VHF omnidirectional range (VOR) navigation system. VAR provided four courses for navigation, two using visual instrument signals functionally and technically similar to the modern localizer and backbeam components used in the ILS system and two using audio signals similar to the LFR system. VAR also used marker beacons similar to the ILS.