During this time, he was trained on jet engine-powered aircraft.

The PA-1 was the first air-cooled, radial engine-powered aircraft.

While this design would have been feasible, the Italian Air Ministry required that the plane satisfy the same structural requirements of an engine-powered aircraft.

It is still used as an additive in aviation fuel for piston engine-powered aircraft, and also in high-octane automotive racing fuels.

The German aviation company Dornier Flugzeugwerke based most of their production in the town from 1922 to 1932, after The Treaty of Versailles of 1919 banned construction of engine-powered aircraft in Germany.