Airways

from JROTC.org AIRWAYS

Aircraft flying in FAA controlled airspace normally operate on three dimensional "air highways" These three dimensional "air highways" are called Airways and are depicted on air navigational charts. There are two classes of airways: Low-altitude airways (1,200 feet above the surface to 18,000 feet above mean sea level--MSL) are known as Victor airways based on the locations of VOR radio navigation stations. High altitude airways (18,000MSL to 45,000MSL) are also based on VOR stations, but because of their higher altitude and often greater speed, pilots are able to use VOR stations at greater distances from the aircraft. Pilots who fly the high altitude airways must also fly by Instrument Flight Rules--IFR.