How To Know What Service Volume A Vor Is

Practise you recollect the service limits of a VOR? How about how to avoid opposite-sensing? Here's what y'all need to know most how VORs work for your next flight.

What Exactly Is A VOR Station?

A VHF Omni Directional Range Radio (VOR) is the most common basis-based navigational aid (NAVAID) yous'll use. VOR navigation allows your to fly signal to indicate along established airways between VORs. Here'southward what a VOR station looks like:

While some VORs are being slowly phased out by the FAA, there are still hundreds of VOR stations around the country. They're valuable sources of position information for cross country flights, musical instrument approach procedures, and if you go lost, they can help you chop-chop pinpoint your position.

How VORs Work

The frequency range for a VOR is between 108.0 MHz and 117.95 MHz. Every VOR is oriented to magnetic north (more than on this in a flake), and emits 360 radials from the station. The VOR sends out one stationary master signal, and 1 rotating variable signal. These are too called "reference" and "variable" phases.

An shipping'southward VOR antenna, which is usually located on the tail, picks up this signal and transfers it to the receiver in the cockpit. The aircraft's VOR receiver compares the difference between the VOR's variable and reference phase, and determines the aircraft'south bearing from the station. This bearing is the radial that the aircraft is currently on.

Virtually VORs have distance measuring equipment (DME) or tactical air navigation equipment (TACAN) installed within the VOR station. When a VOR is collocated with DME, it'south labeled as "VOR-DME." On the other manus, when a VOR is collocated with a TACAN, it'due south called a VORTAC. You lot tin observe them charted on VFR Sectional Charts, IFR Low Charts, IFR High Charts, SIDs, STARs, and Instrument Approaches. Here's what VOR symbols look similar:

The vast majority of VORs have DME, and when they do, yous can tell how far you are from the station by using a readout display in your cockpit.

Know Your Service Volumes

VORs are express to line-of-sight. Obstacles, terrain, and even the gradient of the earth interfere with VOR signals. There's no restriction on how many airplanes can employ a single VOR simultaneously. There are three classes of VORs: Terminal (T), Low (L), and High (H). Y'all can expect your VOR upwardly in the FAA Chart Supplement to determine what category it is.

The farther away you are from a VOR, the higher you demand to fly to get signal reception. This is why VOR service volumes have a gradient at the everyman altitude, to account for terrain and curvature of the earth.

Even though VORs take been around since the 1940s, they're not going abroad anytime shortly.