Heavy bomber version of the bouncing bomb, was used to destroy the Mohne and Eder dams by Lancasters from the specially recruited and trained 617 Squadron, often known as the Dambusters, under Wing Commander Guy Gibson. In March and April 1945, as the war in Europe was ending, Lancasters dropped Grand Slams and Tallboys on U-boat pens and railway viaducts across north Germany. At Bielefeld more than of railway viaduct was destroyed by Grand Slams creating an earthquake effect, which shook the foundations. The Boeing B-29 Superfortress was a development of the Fortress, but a larger design with four Wright R-3350 Duplex-Cyclone
Wing commander (rank) rank of colonel. In the United States Air Force (USAF) wing commander is a duty title, not a rank. The equivalent USAF rank is lieutenant colonel who typically has command of a squadron. Because USAF wings are larger formations than RAF wings, the commander of a wing must hold at least the rank of colonel, and is typically a colonel or a brigadier general. The one exception to this is the commander of the 59th Medical Wing (Wilford Hall Medical Center) who is customarily a major general. The Civil Air Patrol, the volunteer auxiliary of the USAF, follows the USAF