Aircraft in the Unlimited class, which consists almost entirely of both modified and stock World War II fighters, routinely reach speeds in excess of 400 miles per hour. In 2003, Skip Holm piloted Terry Bland's modified P-51D Mustang, Dago Red, and reached an all-time Unlimited class speed record of 507.105 mph in a six-lap race around the eight-and-a-half mile course. The recently added Sport Class racers, mostly homebuilt aircraft, are reaching speeds in excess of 400 mph. In 2009, Curt Brown set a record of 543.568 mph in his jet-engine L-29 Viper.