Sometimes you will see the word spelled Rallye. While this is generally used internationally, some people use it to differentiate this event from some political gathering. A rally is generally a competitive event. They are normally run over public roads.
Many clubs have rally programs; their rallys will generally be either Gimmick or Time-Speed-Distance (TSD).
Gimmick Rallys vary widely; the topic is far to broad to cover in a brief note. Generally these are low key events where the primary object is to have fun, rather than serious competition. A Gimmick rally is a very good way to introduce yourself to the sport of Rally. Normally a Gimmick rally will have some puzzle to solve. Often the contestants must search for answers to questions, which may provide clues to where the rally route goes, and might be answers to questions about signs and buildings on the route. The Gimmick may be to draw a playing card at each checkpoint, also known as a control, and the best pokerhand wins. Most, but not all, Gimmick Rallies are won by luck or chance, rather than skill. That is why they are not considered competitive.
TSD Rallys are generally thought of as "more serious" than Gimmick Rallys. They are called TSD because one of the three variables in the equation D = RT are given, where D is the distance to travel, R is the speed to travel at, and T is the time to travel in. Normally the variable given is R which is typically 10% below the speed limit (it varies depending on the type of rally being presented.) This is the AVERAGE speed you must travel. If you slow down for a corner, or stop for a sign, you will have to go faster than that average to make up the time you lost. The Checkpoints, or controls as they are also called, will note the time you arrive at their location. Generally for every 0.01 minute (0.6 seconds) you are early or late you recieve one point. The team (Driver and Navigator) who scores the lowest points (minimum error) wins their class.
This would be easy if you knew where the controls were. That is a carefully guarded secret. You are provided instructions which will take you along a very specific route. Normally this lets you do some senic driving out in the country, as most rally routes try to avoid congested areas as much as possible. This distance is carefully measured, and since the rate (R) is known, the your perfect arrival time (PAT) is known. However your team must not only calculate your perfect arrival time, but you must drive it as well. The type of route instructions also determines whether you are participating in a tour or course rally.
Tour Rally instructions give you specific and clear instructions as to the rally route. Course Rally instructions may include traps that will if taken cause you to travel either shorter or longer than the intended distance. This will cause you to enter the control either earlier or later than your perfect arrival time, thereby affecting your score. Essentially in Tour Rallies, you only need to concentrate on staying on time. Course rallies require not only staying on time but on course as well. Sometimes rallies are advertised as being "brisk"; this means that the average speeds given are very close to the speed limit, and the roads are twisty or offer the driver some other challange. This adds an additional dimension, since driver ability also comes into play as well.
TSD rallys are offered on a low key basis by many clubs, and there are SCCA National and Divisonal series for more serious competitors.
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