Gliding Competitions - Racing Strategy and Tactics

Racing Strategy and Tactics

Races are won on the basis of speed over the day's course. Time on course is measured from when each pilot leaves the start zone until they finish. Each competitor may elect to start any time after the start opens. To allow all competitors sufficient time to get into a good position to start, competition rules specify that no competitor may start until twenty minutes after the last competitor has launched. The start can be a line, or it can be a cylinder several miles in radius. In both cases there is a specified maximum altitude for the start and competitors typically will attempt to start as close to the maximum start height as possible.

One of the more important decisions of a flight is when to start. This decision is based mostly on each pilot's desire to be on course during the strongest weather conditions of the day. There are also competitive considerations. Often competitors will try to start just after other pilots, using them as "markers" for favorable lift conditions ahead on course. Using this technique, a skilled pilot can make up several minutes on the earlier starters during the early portion of the flight. Pilots who are being followed in this way may use a variety of tactics to shake off pursuers, such as doubling back after a start and starting again. Each pilot may start as many times as he or she chooses - only the last start counts. However, playing an endless game of "start gate roulette" can have disadvantages. Late starters can find themselves still out on course when the soaring weather becomes weak or wholly unsuitable. The best pilots are therefore also good weather forecasters.

The most important factors influencing the overall speed at which glider can fly around a given course is the average strength of the rising air the pilot chooses for climbing and the directness of the route chosen around the course (no credit is given for deviations, but a detour to reach stronger lift can often more than make up in speed for the extra distance travelled). Experienced pilots typically pass by relatively weak lift, selecting only the strongest lift for climbing. However, being too selective runs the risk of getting too low to the ground and being forced to accept any available sources of rising air (no matter how weak) in order to avoid "landing out". This can cost the competitor valuable time. The best pilots also are expert at getting the most out of each source of lift by maneuvering their glider quickly to the center of the lift where the rate of climb is greatest. They also are highly skilled as using a wide variety of information (weather forecasts, terrain features, clouds, other gliders on course) to estimate what conditions are likely to be like ahead on course and adapt their flying tactics to maximize their overall speed.

It is often possible to fly efficiently by merely slowing down in the rising air while flying straight ahead on course, instead of circling, then speeding up again when the air is no longer rising. This technique is known as 'dolphining'. If the conditions are favorable, the glider can gain enough energy from each source of lift and maintain its overall height for long distances without circling. Days with steady, moderate winds can be good for this, as the thermals often will line up into cloud streets, enabling the pilot to race without having to turn. Choosing a flight path directly on course line may not be the best tactic if a slight diversion can keep the glider in rising air for longer, or at worst keep out of the strongly sinking air.

Throughout the task gliders will often fly together in 'gaggles', because a group of gliders is more likely to find better lift than one glider on its own. Pilots sometimes have to decide whether to stay with a gaggle or go on their own in another direction where they believe there will be better lift. On days when there are no cumulus clouds to indicate where there is lift, gaggle flying is the norm. However gaggle flying makes it more difficult for a pilot to gain significantly more points than the other competitors.

One of the last key decisions that each competitor makes is determining when the glider is high enough to reach the finish line. This is a critical decision because, on the one hand, taking on unnecessary altitude wastes time because there are no points gained for arriving high at the finish. On the other hand, running out of altitude before the finish can result in a costly (and embarrassing) "land-out". For any given lift conditions, there is an optimal final glide speed to minimize the overall time required - the stronger the lift, the faster (and steeper) the final glide should be. Pilots use sophisticated glide computers to calculate the altitude required and to track progress along the way. Most pilots plan their final glide with extra altitude ranging from several hundred to more than a thousand feet as insurance in case unanticipated sinking air is encountered on the final part of the flight.