“Der Adler” was a bird-like monoplane designed by Karl Vogt and Johann Stockhausen, displayed at the “Schützenplatz” in Paderborn in October 1909. The 17 m long machine of 9 m span did apparently not fly, not even with the help of a 60 hp Dürkopp engine.

Based on the Taube design and built by Richard Vogt when he was just 16-years old, this machine was test flown on the Mutlanger Heide but unfortunately crashed on its first flight. Vogt designed this 30 hp Anzani-powered monoplane together with an unknown friend during 1911 through early 1912.

In 1913 the English Marconi Company commanded Vlaicu to create a two seat aircraft out of metal. After a few months, the Vlaicu III was finished. The Vlaicu III was the first fully functional aircraft in the world built in metal.

In 1911 Vlaicu built a second plane which he flew in several cities in the Kingdom, in major tournaments.

The most distinguishing feature was the now fully enclosed nacelle. In front of the nacelle was a Gnôme 7-cylinder rotary engine delivering 50 hp, driving the two propellers via a chain. This machine participated in the June 1912 competition at Aspern flying field at Vienna.

He participated in the war during the Balkan campaign, where he performed some aerial observation missions.

Supported by the Royal House and the Romanian Army, Vlaicu started building at the workshops of the Army Air Arsenal the Vlaicu I, the first plane built on Romanian territory.

Vlaicu first flew the aircraft on 17 June 1910 above the Cotroceni field.

At the urging of his school friend, the poet Octavian Goga, Vlaicu went to Bucharest, where in front of an audience he demonstrated his prototype aircraft.