At that time Wernher von Braun decided not to start their own rocket engine development, but to purchase an engine from North American Aviation (NAA) that was being developed by Dannenberg's former boss, Riedel, who had previously left the team to join NAA. Beaumont Hospital, and were eventually transferred to the Redstone Arsenal near Huntsville, Alabama, where development of the PGM-11 Redstone Missile was their first assignment.
When the Korean War started, the group were required to leave their quarters in an Annex to the Wm. Goddard's idea of upper atmosphere research could now be conducted on a large scale. Due to range limitations, all rockets were launched vertically, to limit their range. Army and the support contractor General Electric to launch V-2s at the White Sands Proving Ground. Most members of the group performed calculations and designs of future advanced launch vehicles with longer ranges and greater payloads. Dannenberg then became Walter Riedel's deputy and headed the crash effort to finalize production drawings of the V-2, the world's first ballistic missile and used by the Nazis to bomb London.Īfter the end of World War II, Dannenberg was brought to the United States with 117 other German specialists under Operation Paperclip to Fort Bliss, Texas.
After Thiel's death in an August 1943 bombing raid, a design freeze stopped all development efforts. Many improvements on which he worked could not be completed in time for production. He was at Peenemünde on 3 October 1942 to witness the launch of the first V-2 rocket (which means that he saw the first manmade object to reach outer space). His main assignment was developing a rocket engine for the V-2 ballistic missile. Under Walter Thiel's guidance, he became a rocket propulsion specialist. In Spring 1940, through the influence of Püllenberg, Dannenberg was discharged from the army and became a civilian employee at the German Army's Research and Development Center in Peenemünde. He took part in the initial stages of the Battle of France. When World War II began, Dannenberg, a member of the Nazi party since 1932, was drafted into the German army in 1939, serving first with a horse-artillery unit acquired by the German Army in Czechoslovakia. Dannenberg studied mechanical engineering at the University of Hanover with emphasis in diesel fuel injection, because he recognized that injectors would also be part of the process of moving propellants into a high-pressure rocket engine. He witnessed two tests with a rocket-driven railroad car in Burgwedel near Hanover and then joined Albert Püllenberg's group of amateur rocketeers. He became interested in space technology while attending a lecture by Max Valier, a German pioneer in that field. At the age of two, he and his family moved to Hanover, where he spent his youth. Dannenberg was born in Weißenfels, Saxony-Anhalt.