Germany decided to put both the V-1 and the V-2 into production. On September 29, 1943, Albert Speer publicly promised retribution against the mass bombing of German cities using a "secret weapon". On June 24, 1944, the Propagandaministerium (Reich Propaganda Ministry) announcement of the Vergeltungswaffe 1 guided missile implied there would be another such weapon. Development During World War II, several projects were undertaken by the German Navy at Peenemünde Army Research Center to develop submarine-launched rockets, flying bombs and missiles. These projects never reached combat readiness before the war ended and the German Navy did not use submarine-launched rockets or missiles. Short-range rockets According to Walter Dornberger, Ernst Steinhoff, the Director for Flight Mechanics, Ballistics, Guidance Control, and Instrumentation at Peenemünde Army Research Center, whose brother Kapitänleutnant Friedrich Steinhoff commanded the U-boat , originated the idea of launching solid-propellant rockets from a submerged submarine. Ernst Steinhoff was Tubular metal launch frames (Schwere Wurfgerät 41 (sWG 41)) carrying six 30 cm Wurfkörper 42 rockets were mounted on the submarine's upper deck with a 45° firing angle. From May 31 to June 5, 1942, under the code name "Project Ursel", a series of solid-fuel rocket launching experiments were carried out using submarine as a launching platform near the Greifswalder Oie. Successful firings from the surface were carried out on June 4, 1942, and from up to underwater with no effect on the missiles' accuracy. The rocket system was first envisaged as a weapon against convoy escorts but with no effective guidance system, the arrangement was ineffective against moving targets and could only be used for shore bombardment. The development of this system ended in early 1943 because it was found to decrease the U-boats' seaworthiness. From 1944 to 1945, the German Navy continued to develop and successfully tested various short-range rockets that could be launched from submerged submarines at depths of up to at the naval testing station operated by the Torpedoversuch Anstalt Eckernförde at Lake Toplitz near Bad Aussee, Austria. No official records on the deployment of these short-range rockets on German U-boats or their use against targets have been found. The first recorded attack on land-based targets using sea-based rockets was carried out by the US submarine on June 22, 1944, against the Japanese town Shari. The USS Barb fired 12 5-inch rockets Mk 10 Mod 0, from offshore, using a rocket launcher Mk 51 Mod 0 installed on