how gliders get in the air and stay up for so long!

A glider a light aircraft that is designed to fly for long periods of time without using an engine. you may be asking yourself how they stay for for so long or how they even get in the air! To start off with, Gliders have multiple ways to get into the air. the way that I use and is the most common to use in the United States is called an Aero tow launch. How this works is a 200ft rope (rope sizes can vary) connected to a tow plane that will pull me up to altitude and ill release whenever I get as high as I want to go (I normally go to 3’000ft). Other ways that gliders can launch include winch launches and auto launching. Winch launching is a big cable connected to a really powerful engine, the engine winches in the cable thus pulling the glider at a high enough speed that it will fly. Next is auto launches, you just simply hook up a cable to the truck/car that will be towing, hook up the glider, and drive! While airplanes and gliders share many design, aerodynamic, and piloting factors, the lack of an engine fundamentally changes the way a glider flies. once gliders get in the air, our first mission as glider pilots is to find a source of lift! There are three different types of lift that gliders can use.

  1. Thermal Lift
  2. Ridge Lift
  3. Wave Lift

Thermals are columns of rising air created by the heating of the Earth’s surface. Air near the ground expands and rises as the surface of the Earth is heated. Certain types of terrain absorb the sun more rapidly than others, like: asphalt parking lots, dark fields, rocky terrain, etc. These spots absorb heat, and heat the air above them, producing thermal air currents.

Ridge Lift is created by winds blowing against mountains, hills or other ridges. Along the windward side of the mountain, a band of lift is formed where air is redirected upward by the terrain. Typically, ridge lift extends only a few hundred feet higher than the terrain which produces it. Pilots have been known to go “ridge soaring” for thousands of miles along mountain chains.

Ridge lift diagram

Wave lift is similar to ridge lift in that it is created when wind meets a mountain. However, wave lift is created on the leeward (downwind) side of the peaks by winds passing over top of the mountain. Wave lift can be identified by lenticular cloud formations - they look like flying saucers. Wave lift can reach thousands of feet high, and gliders riding on wave lift can reach altitudes of 35,000+ feet.

wave lift diagram

Once we get out of a thermal, our next mission is to find another thermal. im currently gliding in Zephyrhills, Florida. My club has a 235hp Cessna 175 (tow plane) and a 235hp Pawnee (tow plane). We have multiple gliders that include Blantik L-23, Schweitzer 1-26, Schweitzer 1-36, Schweitzer 1-35, Grob 103 Twin, and Grob 103 Twin Astir. I absolutely love flying these beasts and it has helped my flying ability in sao many different ways that i just cant explain. for instance, powered aircraft pilots are told to push down through the lift when they hit it and glider pilots are taught to circle up inside of it. It’s just so surreal being in a thermal with all of your friends for hours on end.

if you have any questions feel free to comment or PM me. Thanks!

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