``Top Gear'' host Richard Hammond hits the road to take the ultimate driving test on ``Richard Hammond's Crash Course.'' Traveling across the U.S., Hammond learns how to operate some of America's largest and most-dangerous vehicles. It usually takes years for people to master the vehicles, but Hammond has just days to master the machines while immersed in some of the country's extreme environments. Throughout his journey, Hammond works with local experts, who operate the machines daily, while getting a taste of American hospitality. Some of the vehicles Hammond operates are an Abrams tank, the world's most-powerful fire engine and a two-ton wrecking ball. Each expert Hammond works with decides if he has successfully completed each challenge.