VOR (or VHF omni-directional radio range) beacons are used to marked out many of the world's airways and provide terminal approach aids.

Bearing information from these beacons can be presented to the pilot in many different forms and an understanding of these displays is essential for the correct performance of navigation procedures. VOR beacons are often integrated with DME (Distance Measuring Equipment) providing range information.

Sphaera's VOR Trainer, in use with pilot training schools and maintenance training schools, enables the student to quickly gain familiarisation with various forms of VOR or ADF display.