The Douglas SBD Dauntless dive bomber became a mainstay of the Navy's World War II air fleet in the Pacific, with the lowest loss ratio of any U.S. carrier-based aircraft. The SBD Dauntless featured "Swiss cheese" flaps -- dive brakes punched with 3-inch holes -- so that it could achieve pinpoint accuracy by diving to the target, dropping the bomb and then pulling out of the near-vertical dive.