German aerodynamicist, working in guided missiles during World War II. His studies at the University of Aachen were interrupted by the war, and he was assigned to do research with Versuchskommando Nord. At Peenemuende he was involved in the aerodynamic design of the A9/A10, A7, A4b, and Wasserfall winged missiles. As of January 1947, was living at Bohn am Rhein. Thereafter evacuated to Bavaria. He returned to Aachen and finally completed his diploma in 1947. He then went to the United States and became part of Von Braun's rocket team at Huntsville. As of 1960, Head of Aerodynamics Analysis Branch, Aeroballistics Division, NASA Marshall Space Flight Center.
Werner K. Dahm, an internationally recognized rocket pioneer from WWII whose work in Germany and in the U.S. made important contributions to the nation's ballistic missile programs and its manned and unmanned rocket programs, died on January 17, 2008 in Huntsville, Ala. He was the last of the German rocket scientists to work at NASA, and continued to work there until this past year. His death at age 90 marks the passing of an era in the nation's history.
He was the aerodynamicist in the future projects group on the original team of German rocket scientists working at Peenemuende with Wernher von Braun during World War II, when supersonic and hypersonic aerodynamics were still in relative infancy. He went on to make pioneering contributions in high-speed aerothermodynamics in the U.S. Army's ballistic missile development program, and in NASA's manned and unmanned space flight programs. He was Chief of the Aerophysics Division at NASA's Marshall Space Flight Center, and later Chief Aerodynamicist at the NASA Center. When he finally retired in 2006, at the age of 89, he was the last of the original German rocket scientists at NASA.
Werner Karl Dahm was born on Feb. 16, 1917 in Lindenthal near Koeln, Germany, the son of Anton Dahm and Maria Morkramer. The family moved to Bonn later that year. His father was the first engineer in a long line of merchants. After graduating from the Beethoven School in Bonn in 1936, he studied aerodynamics and aircraft design at the Technical University in Aachen, and later in Munich when the Nazis had closed other technical universities. In Munich he was one of just four students, out of several hundred, who refused to join the Nazi student club. He said he first simply pretended not to find it, and then since it was formally listed as a dueling club he avoided it by claiming religious objections. For this he was denied access to certain advanced aircraft courses, so he focused on courses relevant to rocketry. Before completing his degree he was drafted at the end of 1939, and sent with a signal corps unit to France and then to Czechoslovakia. In between, he was granted a one-semester break to complete the major part of his aerodynamics degree.
As a result of his technical background, in late 1941 he was assigned to the German rocket development effort at Peenemuende, led by Wernher von Braun. There, as the youngest member of the rocket team, he worked in the future projects division, a group composed mainly of physicists who needed a specialist in aerodynamics. At the time, theoretical understanding of high-speed aerodynamics was still in its infancy. He was one of a group that conducted pioneering experiments in a small supersonic wind tunnel to obtain essential insights and data to support designs for proposed new rockets. Among these was the A9/A10 rocket, designed to be the first intercontinental ballistic missile, based on a Mach 6 boost-glide approach using a winged derivative of the V2 rocket. He soon recognized in the wind tunnel results that a shift occurred in the aerodynamic center-of-pressure as the rocket transitioned to supersonic speeds, which would cause it to become unstable. This led to experiments and theories to understand the shift and determine aerodynamic configurations that would allow the rocket to remain stable.
He also worked on the Wasserfall rocket, a radar-guided supersonic anti-aircraft missile, in which the same center-of-pressure shift was being encountered. Along the way, he developed a conical rocket propellant tank that successfully overcame liquid fuel sloshing problems, for which he won an internal prize with a monetary award that he proudly never cashed. In August 1943, when Allied forces bombed the Peenemuende facilities, he received a commendation for saving critical wind tunnel data during the ensuing fires. The Wasserfall project continued almost to the war's end, and the rocket was successfully flown but never went into production. In 1944, he and others in the group were granted civilian status, and resumed the A9/A10 development effort. In January 1945, near the end of the war, two A9 test rockets were launched with control surface designs based on the group's solution to the center-of-pressure shift. The second of these achieved stable transition to supersonic flight.
Facing advancing Russian forces at the beginning of February 1945, he and most others on the rocket team moved to Oberammergau to allow a surrender to American forces. After his release in August 1945, he briefly worked in a candle factory of family friends in Bonn, until accepting an invitation from the U.S. as part of Operation Paperclip to join the U.S. Army's nascent rocket program with other members selected from von Braun's team. He insisted, however, on first being allowed to finish his degree, which was officially awarded in mechanical engineering due to postwar restrictions on further rocket work in Germany. In August 1947 he rejoined the other scientists from the von Braun team at Ft. Bliss, Tex. to begin work on the U.S. rocket program.
In the U.S. he was initially involved in tests at White Sands Missile Range using V2 rockets. These results led directly to the Redstone rocket and laid the basis for every other rocket developed in the United States since. The White Sands work included a Mach 3 cruise missile known as the Hermes II, based on a V2 first stage with a radical linear ramjet concept for the second stage. His work on the Hermes II continued after he moved in 1950 with much of the von Braun team to Huntsville, Ala. as part of the Army's ballistic missile program. There he developed the external aerodynamic design for the Army's Redstone missile, which served as the launch rocket for the nation's first live nuclear missile tests and later also launched the first U.S. astronaut into space. He developed a successful Mach 5 ballistic re-entry nose cone using a purely theoretical approach, at a time when no hypersonic wind tunnels existed to test the theories or provide needed data. He subsequently continued pioneering contributions in high-speed aerothermochemistry in the Army's Jupiter intermediate-range ballistic missile program, and then on the Army's Pershing medium-range ballistic missile and the large Saturn I booster rocket.
Following the Russian Sputnik launch, in July 1960 he moved with other von Braun rocket scientists from the Army Ballistic Missile Agency to the newly founded NASA. There, as part of the Apollo moon-landing program, he made major contributions working on the Saturn V booster rocket, on aerothermodynamics, and on liquid hydrogen propellant systems. He subsequently was involved in numerous projects contributing to the nation's manned and unmanned space flight programs, especially Skylab and the Space Shuttle. In the Shuttle development effort he led a team working on vehicle aerodynamics and the main engines, which included developing full-scale component tests and scaling methodologies, and applying computational fluid dynamics to overcome a wide range of aerothermochemistry problems.
He was Chief of the Aerophysics Division at NASA's Marshall Space Flight Center until 1992, when he became Chief Aerodynamicist at the NASA Center. He was awarded the AIAA Aerodynamics Award in 1997 for his exceptional lifetime contributions to the aerodynamic design and analysis of strategic missiles and manned/unmanned launch rockets, and received the NASA Exceptional Service Medal in 2003. He continued working in science positions at NASA until his retirement, at 89, in 2006. David King, director of NASA's Marshall Space Flight Center, said "America's space program is preeminent because folks like Mr. Dahm contributed to building it into the best in the world. His life and life's work are an example of his energy, dedication and humble leadership, which has played a significant role in humanity's peaceful use of space."
He married Kaethe Elizabeth Maxelon in 1955, who preceded him in death in 1976. He later married Nell Sheppard Carr in 1981, who also preceded him in death in 2000. He is survived by his sister, Hilde Semmelroth of Bonn, Germany, by four sons, Stephan Dahm of Huntsville, Ala., Werner J.A. Dahm of Ann Arbor, Mich., Martin Dahm of Huntsville, Ala., and Thomas Dahm of Plano, Tex., and by two grandsons, Johann Dahm and Werner K.S. Dahm, both of Ann Arbor, Mich.
Birth Place: German.