V-2 rocket offensive began on 8 September 1944, when "Lehr- und Versuchsbatterie No. 444" () launched a single rocket guided by a radio beam directed at Paris. Wreckage of combat V-2s occasionally contained the transponder for velocity and fuel cutoff. The painting of the operational V-2s was mostly a ragged-edged pattern with several variations, but at the end of the war a plain olive green rocket also appeared. During tests, the rocket was painted in a characteristic black-and-white chessboard pattern, which aided in determining if the rocket was spinning around its longitudinal axis. The original German designation of the rocket was "V2",
Type XXIII submarine were subsequently scrapped incomplete, with the others cancelled and never begun; and three hundred at Kiel ("U-4701" to "U-5000"), where twelve ("U-4701" to "U-4712") were actually built although only eight were launched and the other four bombed on 4 May 1945 while still on the stocks (orders for "U-4713" to "U-4891" were cancelled, while "U-4892" to "U-5000" were projected only). The first Type XXIII, , was launched from Deutsche Werft in Hamburg on 17 April 1944. It was one of six XXIIIs that went on operational patrol around the British Isles in early 1945. Forty-eight others followed from Deutsche Werft