Could anybody direct me to a good website where I can understand how the “highways” in the sky were developed and charted… and why???
I have flown the same SWA route between the same two cities countless times - and for many times, it goes the same route… but sometimes, the flight diverts a little off the route. Even in same weather conditions…
Thanks!!!
Here’s a good intro to High Altitude Airways - gelib.com/high-altitude-enroute-charts.htm
Minor deviations can occur if a controller clears a flight to go direct from their current position to a navaid or waypoint farther down along the route, bypassing nearer waypoints that were planned.
Other deviations may occur during the enroute phase to create spacing for traffic the flight would encounter during the arrival phase.
Lets not lie to the guy-
Sometimes Pilots fall asleep, It’s perfectly safe because the auto-Pilot is at the controls.
If the Auto-Pilot detects that the Pilots are asleep (this happens more on Airbus’s then any other airplanes) the Auto-pilot will plot the most efficient course to the destination, it takes the following in this order to consideration-
To keep the pilots sleeping the auto-pilot may also adjust the cockpit temperature. As a pilot you must set an alarm, if you don’t… well ask the guys that over flew Minni 
Thanks for all these responses… What I’m still looking for is how they developed the “highways” in the skies… Surely, they didn’t send out pioneers to scout ahead the mountain passes, etc… How was the whole concept developed??? If I recall right, I’m aware that each 1,000 feet layer level represent a one-way direction for aircraft to ply through… what other concepts were used in developing the “highways”???
In the early days of flight, there were no navigation aids to help pilots find their way. Pilots flew by looking out of their cockpit window for visual landmarks or by using automobile road maps. These visual landmarks or maps were fine for daytime, but airmail operated around the clock. In 1919, U.S. Army Air Service Lieutenant Donald L. Bruner began using bonfires and the first artificial beacons to help with night navigation. In February 1921, an airmail pilot named Jack Knight put this to the test with his all-night flight to Chicago from North Platte, Nebraska. Knight found his way across the black prairie with the help of bonfires lit by Post Office staff, farmers, and the public.
By July 1923, Bruner’s ideas for lighted airport boundaries, spot-lit windsocks, and rotating beacons on towers had taken hold. The Army opened an experimental lighted airway between McCook Field in Dayton, Ohio, and Norton Field in Columbus, a distance of 72 miles (116 kilometers).
Beginning in 1923, the Post Office worked to complete a transcontinental airway of beacons on towers spaced 15 to 25 miles (24 to 40 kilometers) apart, each with enough brightness, or candlepower, to be seen for 40 miles (64 kilometers) in clear weather. On July 1, 1924, postal authorities began regularly scheduled night operations over parts of this route. In 1926, the Aeronautics Branch of the Department of Commerce took over responsibility for building lighted airways. By June 1927, 4,121 miles (6,632 kilometers) of airways had lights. By 1933, 18,000 miles (28,968 kilometers) of airway and 1,500 beacons were in place.
rest of article at centennialofflight.gov/essay … /POL13.htm
Let us not forget Capt. EB Jeppesen who took notes along the routes he was flying. Pretty soon he was making extra’s for his flying buddies. Now his company is owned by Boeing.