Schütte-Lanz (SL) is the name of a series of rigid airships designed and built by the Luftschiffbau Schütte-Lanz company from 1909 until 1917. One research and four passenger airships were planned for post-war use, but were never built. The Schütte-Lanz company was an early competitor of the more famous airships built by Ferdinand von Zeppelin. It is common for all rigid airships to be informally called zeppelins regardless of their manufacturer, and Schütte-Lanz airships are often referred to as such, but the Zeppelin name technically only applies to those manufactured by the Zeppelin company. History When the Zeppelin LZ 4 met with disaster at Echterdingen in 1908, Professor Johann Schütte (1873-1940) started to consider the problems of airship design. He decided, with the co-operation of his students, to develop his own scientifically designed, high performance airship. In partnership with Dr Karl Lanz, an industrialist and wood products manufacturer, he started constructing the Schütte-Lanz Luftschiffbau on 22 April 1909. The airships were successful at first, and introduced a number of highly successful innovations. Wood composites had a theoretical superiority as the structural material for airships up to a certain size, after which the superior strength of aluminum (and later duralumin) in tension was more important than the superior strength of wood in compression. Schütte-Lanz airships until 1918 were made of wood and plywood glued together. Moisture tended to degrade the integrity of the glued joints. Schütte-Lanz airships became structurally unsound when water entered the airship's imperfectly waterproofed envelope. This tended to happen during wet weather, but also, more insidiously, in defective or damaged hangars. In the words of Führer der Luftschiffe Peter Strasser: The decision was made to compensate the company for the unusable wooden ships, and in response the company started work on a tubular aluminum-framed ship which was probably not completed. The German Navy had bases closer to the sea, and thus more humid. They were reluctant to accept wooden composite craft. As a result, the primary customer for Schütte-Lanz airships was the German Army. The German Army decided well before the German Navy that airship operations were futile in the face of land-based heavier-than-air opposition. Twenty-four Schütte-Lanz airships were designed before the end of the World War I, most of which the company was not paid for due to the collapse of the German Monarchy. By the time the last eight ships were ready, most of them could