Thursday 13 January 2011

Helmut von Zborowski - Heinkel annular wing VTOL 'fighter' design concept



Helmut Philip von Zborowski was an interesting figure in early rocket and jet engine development. He is perhaps best known for his work on the Snecma Coléoptère annular wing aircraft during the 1950s - the subject of an interesting new book by Jean-Christophe Carbonel - which stemmed from Zborowski's wartime research on so-called Ringflügel or annular wing concepts for Heinkel.  A contemporary of Werner von Braun, Zborowski worked on rocket and jet development for BMW during World War II and was director of the BMW factories in München-Allach, where engines were manufactured by a huge work force including many thousands of POWs and some 3,000 Dachau concentration camp internees. Zborowski led the team working on the Messerschmitt Me 163 rocket engine and in 1944 was working on rockets as a means of combating the huge bomber fleets operating at will over Germany. With almost continual daytime attacks on its airfields and large scale operations almost impossible, one potential solution for the Luftwaffe was to introduce some sort of VTOL interceptor that could be launched from any open location. Zborowski worked on Heinkel's VTOL design studies as part of their Wespe and Lerche programs. Zborowski's research had shown that performance from a propeller or turbine could be considerably enhanced by the Bernoulli-effect when enclosed in a tube or circular wing, and the Heinkel designs featured "barrel-like" fuselage/wing configurations enclosing the powerplant, surmounted by a small cockpit . The Wespe intended to use a Benz 2,000 hp turboprop engine, but these were not forthcoming and the Lerche used two Daimler-Benz DB 605 piston engines instead. Nothing ever came of either design. Postwar Zborowski went to France and served as a research engineer for the Société d'Etudes de la Propulsion par Réaction (SEPR). Zborowski later founded his own company, Bureau Technique Zborowski. or BTZ which was instrumental in taking his wartime research to a first 'practical' application in the development of the Coléoptère - a type of vertical take off and landing design utilising a ducted-fan as the primary fuselage of the entire aircraft with a small cockpit area suspended above it. Known in English as a "coleopter" Zborowski's machine was designed to take off and land on its tail and carried out nine free flights before crashing. The story of this aircraft and Zborowski's work is related in Jean-Christophe Carbonel's new work on the Snecma Coléoptère annular wing aircraft. More on this work at my blog Jet & Prop by FalkeEins