How Gilders Fly
Unlike powered aeroplanes gliders are completely engineless. As a result gliders have to use other methods of getting airborne and staying up in the air! But gliders have all of the same controls that normal aircraft have so the flight controls are very similar. Read on to find out what gliders are, how they are controlled, launched and how they manage to stay up in the air without that noisy engine!
Gliders
Gliders are also known as sailplanes and range from the cheap to the expensive. They come in two seater and one seater versions. Two seater gliders tend to be used for training although there are high performance modern two seater gliders which can be used in competitions. Single seaters tend to have better performance than two seaters but this is dependent on the type.
Gliders come in different types: wood, fabric and fibreglass.
When you start your training you will be learning in a two seater ASK 13 (themost popular general training glider). However, once you have flown solo and are competent enough you can move onto the club single seater - the ASK 8.
Modern gliders are exceedingly high-tech pieces of equipment, capable of speeds of up to 150 knots (165mph approx) and have incredible performance, some capable of gliding up to 10 miles for every 1000ft of height they have. They truly have to be experienced to be believed.
The Basics
A glider is like any other aircraft except that it doesn't have an engine! Essentially we need forward motion to create "lift" over the wings of the glider. As there is no engine to pull us along we unfortunately have to follow a steady downward flight path - Newton's law always prevails!
Controls
Like any aircraft, a glider has controls which allow you to roll (ailerons), pitch (elevator) and yaw (rudder). Roll and pitch are controlled by the stick - pull back and the nose goes up, push forward and nose goes down, move to the left and you roll left, move right and you roll right. Yaw is controlled with the rudder pedals and is used more than in a normal powered aircraft in order to keep a steady banked turn. Gliders also have airbrakes which reduce lift over the wing and are mainly used during landing to control your descent.
Launching
As there is no engine we rely on other methods to initially get airborne. We use two methods at EGC: aerotowing and winch launching.
Aerotowing involves being towed up into the air by our Pawnee Tug Plane. This is much like towing a car with a long strong rope which attaches glider to tug plane. When you reach your goal height you release and are free to fly the sky - silently!
Winch launching involves being attached to a long run of wire which stretches the length of the airfield. When it is time to go the wire (which you are attached to!) gets pulled in very fast and you accelerate from 0-60 mph in a few seconds! When you reach enough speed you climb high into the sky and you release the cable when you reach the top. You're off!
Staying Up
To stay up in the air we have to find columns of rising air called "thermals". Thermals are ultimately created by the energy of the sun heating the surface of the ground. Eventually the ground is heated enough to produce rising air. Once we have found a thermal we can circle in it and be carried upwards! However, this is only one way of staying up. We can also use rising air that is forced up a hill (or ridge) - know as "ridge lift". Even better lift can be gained when air has passed over mountains and hills - also called "wave". If you find a good wave then you can expect to reach heights of over 20,000ft quite quickly and the record is nearly 50,000ft!
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