Unlike most sports, the playing field in the halfpipe competition doesn't have fixed dimensions. So while every halfpipe abides by a similar blueprint, in the details each one is unique and variations can be great. A halfpipe's designer decides on the pitch, slope, and height. While the effect of the pitch and slope is obvious – a steeper pitch and slope results in more speed – the varying heights of halfpipes are more give and take. "I've seen 14-foot halfpipes up to 1 foot half one," Dumont says. "That was standard for a good six years, and now we have the 22-foot halfpipe, which means there's more transition and a little bit more room for error."
As skiers come down one wall, they cross the flat bottom while building up speed for their next aerial, and into the transition and vertical or "vert" parts of the wall. It's in the vert where designers have the biggest impact. "It's what brings you back into the pipe," says Dumont. "If you don't have enough vert, it doesn't matter how hard you push off the wall – you're going to land on the deck. So vert is very crucial."