Heavy bombers can fly the farthest and carry the biggest payloads of any bomber class. Two of the most famous heavy bombers of World War II were the British Avro Lancaster and the American Boeing B-29 Superfortress. Lancasters were the most prominent bombers used in the European theater and comprised the main force at the firebombing of Dresden. With a massive wingspan measuring over 140 feet, the Superfortress was produced by the thousands exclusively for the war with Japan. The atomic bombs at Hiroshima and Nagasaki were dropped from B-29s. The Superfortress also saw extensive action in Korea, and five specially trained B-29 crews stood
ready to drop atomic bombs there as well.