Back in the early 20s, Alexander Lippisch began to deal with structures or flying wing tailless aircraft projects.
In the research department of the Rhon-Rossitten Society (Department of Aeronautics RRG) Lippisch began to deal intensively with the problem of the intrinsically stable wing, which should carry an aircraft fuselage. Experimentally, he finished his theoretical results through flight tests with big fly models (model scale 1:3), which had a wingspan of 4 meters and more. Due to their size and weight, the models had to be started with the help of a catapult. Characteristic two main directions like the construction of the wing emerged: the swept-wing with wing end and the less well-known form of the “flying plank” in swept-wing shape. Both types proved, depending on the design, awarded as intrinsically stable.
The first flying triangle formed
The stock with swept wings “stork-type,” the flyer of Lippisch was called, had no means exhausted his entire development potential end of the ’20s. Lippisch saw more opportunities in the development of tailless aircraft type for flying wing aircraft. By improving the structure of a wing aerodynamic high-quality, low-wing cantilever should be with a nearly triangular wing layout with full side profile from the stork type. Lippisch with the new wing shape could also use an improved wing spar system, which was placed in the aerodynamic axis of the wing and thus ensured a higher bending and torsional strength.
Delta I is built and proven
Already in December 1929 began the initial work on the project. The following model flight tests were very successful and allowed the first attempt to construct a non-motorized aircraft. This model was designed as a high-wing monoplane. But this design was to change with the engine in a low-wing monoplane. The aircraft was completed in time for the Rhon competition completed in 1930 and was without incident, test pilot at Lippisch, to be flown. All claims of Lippisch were met after thorough testing of the Gleitfliegers. Lippisch took this as an opportunity for the plane to turn into a low-wing monoplane, with a nose gear and a motor of the type Bristol Cherub III equipped with an output of 36 hp at the rear of the fuselage.
Granted a long life
How do you get to read it in the history of aviation repeatedly, experimental aircraft have a long experience in general. At least if this is the for most of these aircraft. As well as for the Delta I. He was lost in a test flight in adverse weather conditions. Although the German pilot man could jump with a parachute, but was injured seriously when landing. The time of the accident is not entirely clear and is set in different sources in the period between 1932 and 1933. One thing is certain in any case that the aircraft from 01 to 23 October 1932 was issued on DELA in Berlin. Experts, therefore, rely on a later date.