Under Construction

VORs

In the United States, the Civil Aeronautics Administration commissioned the first VOR in 1947, and three years later opened the first "Victor" airways based on chains of the facilities. Modernized versions of these navigation aids still guide pilots to their destinations. To take a closer look at a representative VORTAC and its place in the world (the Coaldale, Nevada VORTAC looking slightly rough), click here.

Some representative VORs

Below, on the left, is the Burley, Idaho VOR/DME, and on the right, the Maxwell, California VORTAC. Apart from the color, the most obvious difference is the TACAN equipment at the top of the Maxwell VORTAC. It appears that most, if not all of the VORs in the FAA's Northwest Mountain Region have been repainted in the gray color shown. The traditional white color of the Maxwell VORTAC is still common in the Western Pacific Region.

Burley, Idaho VOR/DME (BYI)	Maxwell, California VORTAC (MXW)
Ely, Nevada, VOR/DME (ELY)	Cutaway of VORTAC/VOR/DME

Note the new gray color scheme of the Rome, Oregon VORTAC shown below, as well as the difference between the top, TACAN section of this VORTAC and that of the Maxwell VORTAC shown above.

Rome, Oregon (REO) VORTAC

Below are shown two VORs which look similar to those above, but are not. On the left is the Northbrook VOR/DME. This VOR is situated on a counterpoise much higher above the ground than the ones shown above. Such positioning gets the VOR above the surrounding obstructions--obstructions which can lead to scalloping in the signal. However, the most important difference between the VORs above and those below is that those shown below are doppler VORs (DVORs). DVORs operate differently than traditional VORs or VORTACS and can be identified by the larger number of small "chicklets" around the outside of the center antenna. While traditional VORs and VORTACs have 16 monitors around the circumference of the counterpoise, DVORs have 50 VHF loop antennas which transmit, rather than monitor, the VOR signal. The DVOR on the right is the Peking/Beijing (PEK) DVOR.

Northbrook, Illinois VOR/DME (OBK)	Peking (Beijing) Doppler VOR, China (PEK)