Diskussion:Helmut von Zborowski
zur weiteren Auswertung:
"Bureau Technique Zborowski (BTZ) • Founded in France by Austrian Helmut Graf von Zborowski (1950) to study annular wing VTOL designs – substantial structural weight reduction – propulsive/aerodynamic efficiency at high speed • Studied manned and unmanned VTOL applications • Licensed concept to SNECMA in 1951 • Coined the term “Coléoptère” = “sheath wing” or “beetle” =================================00 THE ANNULAR WING Snecma’s first projects focused on “tail sitter” aircraft, like prototypes developed by U.S. companies Convair (XFY-1 Pogo) and Lockheed (XFV-1), which would fly in 1954. The focus gradually shifted to a rather original, even revolutionary concept: the annular wing, based on the work of Austrian Helmut Graft von Zborowski. During the second world war Zborowski worked on the Messerschmitt Me- 163’s Walter rocket engine at BMW, and also began to take a closer look at annular wings. More compact than a conventional wing for the same surface area, the annular wing would reduce the aircraft’s structural weight while improving aerodynamics. According to the inventor, the fact that the powerplant was located inside the annular wing meant that it could also be used as a ramjet (1) for high-speed flight. Invited to continue his work in France, he founded the Bureau Technique Zborowski (BTZ) in 1950, along with a small team of engineers. Their drawing boards began to feature aircraft fitted with annular wings, forming a sort of shell around the fuselage and inspiring the name Coléoptère (from the Greek words koleos, for “sheath”, and pteron, for “wing”), also French for “beetle”. In 1951, Snecma purchased their patent for this design, and adopted the Coléoptère name for their entire STOL program. It was a very ambitious program indeed, since the aim was to build an interceptor capable of flying at Mach 2 or higher. Snecma wanted to combine the cutting-edge technologies of vertical flight, ramjet power and an annular wing – all at a time when the industry was barely moving into the jet age! The French government was at first rather skeptical, but finally agreed to fund Snecma’s Coléoptère program in 1954, with the launch of a program to develop a vertical takeoff fighter. West Germany also contributed significant funding. After joining NATO in 1955, West Germany launched VTOL studies to offset the vulnerability of its airfields, which were under immediate threat from Warsaw Pact nations. A small team of German government officials, plus a large number of engineers were on hand throughout the test program. In other words, the Coléoptère pioneered France and Germany’s subsequent extensive collaboration in aerospace.
"Raketentriebwerke auf der Salpetersäurebasis und ihr spezifischen Antriebsgewichte," An exceptional and rare document reporting the results of research and development work at the German BMW company during World War II. It discusses the advantages (and disadvantages) using nitric acid as an energetic oxidizer for rocket engines.
There is much information about dissolved nitrogen dioxide (NO2 or N2O4), to raise the oxidizer density and enhance hypergolic properties. Also, there are details about suitable additives to effect a lower freezing point. Complete information is given for nitric acid decomposition (including the corresponding thermochemical equations).
Extensive graphs and charts illustrate consumptions, temperatures, reactivity, Isp, and specific weights of nitric acid use with alcohol, orthotoluidine, and other rocket fuels. Combustion chamber pressures, feed systems, operating considerations--including suitable metals, alloys, and other materials (ceramics, baked enamels, coatings and caulkings, mainly developed by the I. G. Farben Industry Company)--are thoroughly investigated. Exotic inert sealing liquids are also described.
Particular attention (along with 34 graphs, tables, charts, and photos) is given to comparing nitric acid with hydrogen peroxide (H2O2) and liquid oxygen (LOx).
The BMW 109-511 and BMW 109-548 engines (which powered the German Henschel Hs 298 air-to-sea [anti-ship] and the Ruhrstahl X-4 wire-guided air-to-air missiles, respectively) are described. Photos of these engines in operation are also given, but are not of good quality.
The advanced concept of a ramjet engine using nitric acid for additional energy is also discussed.
This is an exceptional book for everyone interested in rocket propulsion with hypergolic nitric acid oxidizer-fuel combinations. It presents abundant data not available anywhere else, and is a fine handbook providing exceptional information for everyone who designs, builds, tests, or uses liquid-propellant rocket systems. "