We have seen that gliders, once airborne, can fly high and remain in the air for long periods. Pure gliders lack a power source to get them in the air. So, how is this done? Some gliders have "self launch" capabilities with retractable engines and propellers representing the expensive, complicated high end of the sport. "Motorgliders" provide the convenience of independent operation. To me, the low cost and simplicity of pure gliders has a special attraction.
The most common launch method in the USA is to tow gliders aloft with an airplane. Typically, an old crop duster like a Piper Pawnees is fitted with a tow hitch on the tail wheel. A 200 foot, 9/16" diameter poly rope with FAR specified weak links and forged steel rings at each end serves as the tow rope. If you hold a Commercial SEL and have the requisite taildragger time to satisfy insurance requirements, flying a tow plane can be a way to build time although you won't make much money.
For the glider pilot, it's like flying formation on the tugs "6 O-clock" or slot position. Airplane pilots will find holding position behind the tug frustrating at first - but 14-year-olds are known to have mastered it instantly. The skill owes more to riding bicycles than flying airplanes, which gives kids a head start. Like riding a bicycle, a day comes when it just "clicks" and you'll wonder why you thought it hard. The typical tow is to 2000' AGL with the glider releasing and turning right and the tug descending in a left turn for rapid, safe separation. Smart glider pilots choose to release in a thermal and not at a pre-selected altitude. That tow is likely to cost around $50 at a commercial glider operation.
There are many other ways to get airborne. Gliders have been towed by helicopters, dropped from balloons and dirigibles. If you have the right location, it's possible to just push the glider off a mountain. This attractive video is in Polish but you can see such a launch starting at 3:33. http://tiny.cc/ghmNn
The oldest method uses a bungee slingshot affair where two groups of three people each pull on the ends of a rubber rope laid out in a "V". The glider is attached to the apex and held back until the bungee is as tight as possible, then released to be shot off a ridge top. Wile E. Coyote appears to have been a consultant. Watch: http://tiny.cc/hSBt
Outside the USA, the most common launch method is by winch. This takes a bit of explanation so bear with me. A glider winch is a large machine resembling farm equipment with a big engine and a large drum of rope or wire. The winch is positioned as far beyond the departure end of the runway as room permits, and the rope is pulled out to the glider which is positioned at the other end of the runway - often 5000 feet or more away. The glider is pulled toward the winch, accelerating at around 1G reaching 60mph in about 3 seconds. Short of being catapulted off an aircraft carrier or hitching a ride on the Space Shuttle, that's more acceleration than any airplane.
The glider reaches flying speed in about 100 feet and begins a gentle rotation into a 45 degree nose-up climb at around 65 knots airspeed and around 4000 FPM climb rate. The climb continues at 65 knots with gently reducing deck angle until the top of the launch. At that point, the release is automatic - although the pilot will pull the release knob just to be sure. Watch http://tiny.cc/y0hZk or search YouTube with "Winch launch" or the German word "Windenstart"
Winch launch is huge fun, safe, very cheap at around $10 a launch, and a great way to practice landings. There are about 30 places in the US that do winch launch so it's a bit hard to find but well worth it. See: www.ssa.org > "where to fly" or FAST
Club of the week: The Orange County Soaring Association is a great training club who does winch launch at Hemet Airport in Southern California. (http://www.ocsoaring.org)
Wanna race? Next time, put on your parachute and game face and try to beat 50 other pilots around a 300 mile course - all about sailplane racing.