Goddard directly with technical questions. Von Braun used Goddard's plans from various journals and incorporated them into the building of the Aggregat (A) series of rockets. The first successful launch of an A-4 took place on 3 October 1942. The A-4 rocket would become well known as the V-2. In 1963, von Braun reflected on the history of rocketry, and said of Goddard's work: "His rockets ... may have been rather crude by present-day standards, but they blazed the trail and incorporated many features used in our most modern rockets and space vehicles." Goddard confirmed his work was used by von Braun in 1944, shortly before the Nazis began firing V-2s at England. A V-2 crashed in Sweden and some parts were sent to an Annapolis lab where Goddard was doing research for the Navy. If this was the so-called Bäckebo Bomb, it had been procured by the British in exchange for Spitfires; Annapolis would have received some parts from them. Goddard is reported to have recognized components he had invented, and inferred that his brainchild had been turned into a weapon. Later, von Braun would comment: "I have very deep and sincere regret for the victims of the V-2 rockets, but there were victims on both sides ... A war is a war, and when my country is at war, my duty is to help win that war." In response to Goddard's claims, von Braun said "at no time in Germany did I or any of my associates ever see a Goddard patent". This was independently confirmed. He wrote that claims about his lifting Goddard's work were the furthest from the truth, noting that Goddard's paper "A Method of Reaching Extreme Altitudes", which was studied by von Braun and Oberth, lacked the specificity of liquid-fuel experimentation with rockets. It was also confirmed that he was responsible for an estimated 20 patentable innovations related to rocketry, as well as receiving U.S. patents after the war concerning the advancement of rocketry. Documented accounts also stated he provided solutions to a host of aerospace engineering problems in the 1950s and 1960s. On 22 December 1942, Adolf Hitler ordered the production of the A-4 as a "vengeance weapon", and the Peenemünde group developed it to target London. Following von Braun's 7 July 1943 presentation of a color movie showing an A-4 taking off, Hitler was so enthusiastic that he personally made von Braun