Adalbert Schmid Ornithopter

ADALBERT SCHMID ORNITHOPTER

SC-28 WOLKE

(1942)

By Rob Arndt

During the 1930s Adalbert Schmid worked on fixed-wing aircraft as a designer at H&G Pause Modellwerk. Although he had designed a two-seat Mosquito high-wing monoplane by 1939, Schmidt believed that the future of sport aviation (popular at the time) would be revolutionized by his “flapping-wing” (ornithopter) concepts.

First German Ornithopter of 1908

He had been studying this type of flight (like so many of the early aviation pioneers) since 1919 and had even managed to fly some small-scale ornithopter models in free flight with his ultimate goal of building a manned aircraft.

Schmid chose as his test propulsion system “muscle-powered” flapping wings that generated between 180-200 kg of thrust on the ground. While there is some doubt to his claims of the oscillating thrust produced, Schmid continued on to the next step towards construction.

The aircraft built combined both fixed and flapping wings, but in this case the power came only from the flappers while the larger wings acted as mere stabilizers. Only the powered flappers enabled lift for the fixed surfaces.

The craft weighed 60 kg and the larger wingspan was 12.6 meters. The human-powered flappers were each 3.2 meters long. Unlike the traditional flapping up-and-down movement favored by other ornithopter pioneers Schmid opted for a rotary movement, imitating a bird’s upstroke wingspan reduction movements.

Schmid’s ornithopter flew on June 26, 1942 outside of Munich to a distance of 900 meters. After being towed aloft, it maintained a 20 meter height for the entire distance and landed. Schmid considered the flight a success but the nature of the human muscle-power flappers were called into question and Schmid knew that there were limitations to human strength.

Wander 2 SP German motorcycle
with Sachs 3 hp motor

Therefore, he installed a 3 hp Sachs motorcycle engine into the ornithopter to power the flappers and added wheels for take-off and landing. This allowed the aircraft to take off unassisted and the very first test flight which lasted 15 minutes averaged 60 km/h. Fuel consumption was low at 1.5 liters per 100 km. Schmid found that satisfactory, but then upped the ornithopter’s power by installing a 6 hp engine which increased speed to 80 km/h.

After these historic accomplishments, Schmid's work was interrupted by the war situation.

While Schmid continued to make a few scout tests over Munich with the craft which he named “Wolke” (Cloud), the Luftwaffe took some initial interest in the odd machine with provisional designation SC-28. It was thought that perhaps the machine might be modified into a near silent recon plane but the limitations of the flapping wings proved otherwise and the project was cancelled. The Luftwaffe already had plenty of recon aircraft of conventional operation.

Schmid 1947 Ornithopter

By 1947, however, Schmid had constructed a second ornithopter. This one, a modified Grunau-Baby IIa sailplane, was constructed with flapping outer wing sections. Using a 10 hp engine, this two-seater was capable of speeds estimated at 100 to 120 kilometers per hour.

But Schmid, an old man by 1950, lamented that his work had not been continued during the war. Apparently his ornithopter was dismissed as not having any military value without extensive evaluation, even though Schmid had a side-mounted camera installed at his own expense to demonstrate the capability of the Wolke.

Given the war circumstances and bad timing of Schmid's endeavors, it is no surprise that his work went largely unrecognized.

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