Glider Racing

Racing cross-country

The biggest single deciding factor on how fast a glider can fly around a given task is the strength of the thermals (and thus, the available energy). The stronger the climb, the faster the height is gained and the quicker the pilot can fly to the next thermal (the inter-thermal cruising speed can also be increased to make use of the extra energy). The geographical pattern of the thermals is also extremely important, as this can lead to a type of flying called 'dolphin flying'. Rather than stopping and circling in lift, the pilot more or less flies in a straight line, slowing down in the thermal to regain lost energy from the glide and speeding up in the sink on the other side. If the conditions are right, the glider can gain enough energy from each thermal and maintain its overall height for long distances without circling. Thus, viewed from the side, the glider dives down to gain speed ( to get through the sinking air as quickly as possible), and then pulls up sharply in the rising air to maximise the recovery of energy (thus mimicking the motions of a dolphin). Windy days are good for this, as the thermals often line up into 'street's, enabling the pilot to race along an aerial motorway without having to turn.

 Another method of going faster, which is often used on good days, is to make the glider heavier by filling it with water (as much as 400lbs in some cases). Although this may sound counter-intuitive, it enables the glider to fly faster for the same L/D ratio (it will come down faster, but it retains the same glide angle at a higher speed). In effect, a heavier glider can pull more energy out of the system and convert it into extra speed. The penalty being that it will not climb so well, but if the conditions are right for dolphining, or the thermals are big and strong, then the benefits of a higher cruising speed greatly outweigh the penalties. So how does one pilot beat another if they are all flying in similar aircraft in the same piece of sky?

Winning

Very simply, the pilot who only flies in the strongest thermals and does not waste time in weak ones, who flies at the optimum speed between the thermals, who follows the straightest course while using the best energy line (i.e., minimises the time spent in air going down), and when near home, gauges the correct height to make his final glide back to base, will often win the day. But to win the competition, a pilot has to fly consistently over several days. The best pilots are the ones who win by not making mistakes. Quite often, competitions are won or lost by seconds over nine days of flying! Taking one weak thermal, or even a single turn in the wrong place, can lose the competition. It goes without saying that the top pilots have to practice as much as possible (usually in the region of 2-300 hours a year). Being able to fly the glider perfectly is just the beginning; learning to read the sky, map reading, navigation and tactical decisions are all vital. Being able to do this continuously for several hours, often in hot conditions, is also a must. Peak mental and physical fitness are therefore absolute necessities. Late nights, too much booze and the inability to focus will not make you a top competition pilot!  

Not making it to the next thermal, or being shot down by rain, usually means the glider lands in a field. This is not good news when trying to win! Quite often, trying to win the day can lose the competition. The need to 'press-on' to the next super thermal has to be tempered by the fact that most thermals do not exist for very long (5-15 minutes), so the lower the glider gets, the less selective the pilot has to be, or he may end up in a field. Thus, being able to judge the age of a cloud by its looks, or finding a good reliable thermal source on blue days are paramount skills.

Next: Competitions