Archived posting to the Leica Users Group, 2004/06/17[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]
> No major airports in the vicinity but you are absolutely correct. > Closer inspection showed it to be the 'Property of Air Traffic Control > Systems'. That's a VORTAC. A VORTAC is a VOR and a TACAN in the same building. A VOR is a VHF Omnidirectional Ranging beacon. VHF is the name of the radio frequency used. Omnidirectional means it sends in all directions (that's why it has that ring of antennas around it). Beacon means it sends to you, rather than you sending to it. VORs send airplanes signals that the airplanes can use to navigate. A TACAN is a TACtical Air Navigation station. It sends VOR-like signals on a different frequency, and responds to DME (Distance Measuring Equipment) probes from airplanes equipped with it. In other words, a DME-equipped airplane can hear a TACAN, send out a probe saying "How far away am I?" and get an answer back from the TACAN. If I were a Very Bad Person and I wanted to make the world stop, I would coordinate the destruction of a bunch of VORTACS. Airplanes wouldn't be able to fly so well any more.