August von Parseval`s Airships.
On May 26 1906 August von Parseval succeeded launching his new airship at Berlin Tegel military field. In contrast to his rival Zepellin Parseval's airships - also in honor of their inventor called Parsevals - were non-rigid or semi-rigid airships, with little or no stiffening structure inside the fabric envelope. While studying in Augsburg August von Parseval met his future business partner Hans Bartsch von Sigsfeld Together, they made early developments of balloons. Von Parseval devoted his life to aeronautics pretty early and learned the principles autodidactic. His first developments were even used for military purposes, especially for reconnaissance and faced a big success for the engineer. They soon started building a navigable airship and it is assumed that the first successful models appeared around 1901. While trying to land one of the airship one year later a horrible accident occurred and Parseval's partner Sigsfeld away. This resulted in a construction and developing break until 1905. As the development of engines moved forward, Parseval became able to use these for his airship. In the 1920s and 30s the engineer built several keel-airship and Parseval also increased his interest in the construction of crafts heavier than air. His first experiments considering actual planes mainly took place on the water due to safety reasons. However, the first attempts were very unsatisfying and even after a complete re-developments, the planes would never lift off the water. On October 7 1910 Parseval attempted another lift off. This time however, he made sure that the plane would have enough speed for lift off and was successful. In the following months, Parseval reached altitudes of approximately 75 meters, and distances of three to four kilometers. In 1911 the engineer retired from his experiments and started teaching the theories of flight that he had learned during his career. Between 1909 and 1919 about 22 airship were constructed under Parseval's name. The engineer's airship were very popular and seen as a great competition to Zeppelin. In order to stabilize his airship, Parseval used the ability to change the temperature of the gases inside the balloon. In contrast, Zeppelin had used huge metal rods. At yovisto, you may be interested in a video lecture by Randy Friedl on the Opportunities of Airships in Earth Science.