The Mojave Desert’s dry Ivanpah lake bed shimmers under a vicious solar glare,creating the illusion of water. Piercing the mirage are dozens of sails—a vast array of color streaking over a dusty ocean. It’s the last week in March, and Ivanpah is hosting the North American Land Sailing Association’s annual dirt-boat championships, the America’s Cup. It may seem odd to give this competition the same name as the more famous ocean race, but truth be told, in a strictly technical sense the two America’s Cups are quite similar. Dirt sailing is sailing, after all: The tactics are the same; the maneuvers are the same. The main difference, as people who race on dirt are keen to point out, is speed. Sailing on a dry lake is about three times faster than sailing on water.