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
No. 73 Wing RAAF B-25 Mitchells. Flight Lieutenant Bill Newton, one of the Boston pilots who attacked Lae, was awarded a posthumous Victoria Cross for pressing home bombing missions against Salamaua later that month, in spite of severe damage to his aircraft. Having earlier been led by Wing Commander Blake Pelly, by June 1943 No. 73 Wing was under the command of Group Captain Ian McLachlan. That month, McLachlan established his headquarters at Goodenough Island, where the wing was reorganised as a fighter formation consisting of No. 76 Squadron (flying P-40 Kittyhawks), No. 77 Squadron (Kittyhawks) and No. 79 Squadron (Supermarine Spitfires). As well