The downhill is an alpine skiing discipline. The rules for the downhill were originally developed by Sir Arnold Lunn for the 1921 British National Ski Championships.
More generally, the term may be used in any sport involving the speedy descent of a hillside. Examples include snowboarding, mountain biking, different skateboarding variants, such as and longboarding, freebording and mountain boarding and even municycling.
The "downhill" discipline involves the highest speeds and therefore the greatest risks of all the alpine events. Racers on a typical international-level course will exceed speeds of 130 kilometers per hour and some courses, such as the famous Hahnenkahm course in Kitzbuhel, Austria, speeds of up to 150 kilometers per hour in certain sections are expected. Racers must have great strength, stamina, technical expertise and courage if they wish to compete in the downhill.
A typical downhill course begins at or near the top of the mountain on a run that is closed off to the public and groomed specially for the race. Alternating red and blue gates are spaced great distances apart, but not out of sight from each other. The courses in the world's most famous ski areas are preset and predetermined and do not change much from year to year.
The course is designed to challenge the best skiers in a variety of tasks: skiing at high speeds over ice, through challenging turns, extreme steeps and on the flats. A good course will have all these elements in it, as well as some jumps intended to complicate matters and thrill both the racer and the onlooking crowds.
Equipment for the downhill is a little bit different from the other alpine events. Skis are 30% longer than those used in the slalom, to provide added stability at high speed. Ski poles are bent so as to curve around the body as the racer stays in his "tuck." Racers wear skin tight suits to minimize aerodyamic drag and helmets for head protection are mandatory.
In an attempt to increase safety, the 2003-2004 season saw the FIS increase the minimum turning radius for downhill skis to 45m (from 40m), and impose minimum ski lengths for the first time; 215cm for men, 210cm for women.
In all forms of downhill, both at a local youth-level as well as the higher FIS international level, racers are allowed extensive preparation for the race, which includes daily course inspection and discussion with their coaches and teammates as well as several practice runs before the actual race. Racers do not make any unnecessary turns while on the course, and try and do everything they can to maintain the most aerodynamic position while negotiating turns and jumps.
Unlike slalom and giant slalom, where racers have two combined times, in the downhill, the race is a single "run." Times are typically between 1:50:00 seconds and 2:50:00 seconds for the most challenging courses. Tenths and hundreths of seconds count: World Cup races and Olympic medals have sometimes been decided by as little as two or three one-hundreths of a second.
Safety netting and other forms of padding are placed in worrisome areas where race officials anticipate crashes. Despite these safety precautions, the ski racing community is well aware of the inherent risks in downhilling, for it is tragic, but not unheard of, for racers to suffer serious injury or death while practicing or competing. Despite the risks, both racers and eager spectators enjoy the thrills and challenges of the event, and from a racer's point of view, nothing matches the satisfaction and excitement of skiing a particularly challenging course well.