David Schwarz

David Schwarz (20 December 1850 – 13 January 1897) was an aviation pioneer of Hungarian Jewish origin who lived and worked in Croatia. He is known for creating an airship with a rigid envelope made entirely of metal. descended from an old Hungarian Jewish family. In 1865, his mother brought him to Županja, to live with his brother, who was an established trader there. He completed a trade school and became a merchant, running a sawmill in Našice and running a timber business between Koprivnica and Ludbreg, at the time in the Kingdom of Croatia-Slavonia. Since the 1880s, he lived in Zagreb, Kingdom of Croatia-Slavonia.

Problems arose during gas-filling: on inflation, the framework collapsed.

The first airship's specifications were: Power: four cylinder engine weighing producing at 480 rpm Volume: Empty weight: Gross lift: Ballast and fuel: Equipment and three people: Net lift:

The circumstances of Schwarz's return are unclear; there were reports of a hasty departure from Russia.

Second airship in Berlin In 1894, Carl Berg procured a contract to build an airship for the Royal Prussian government, referring to Schwarz as the originator of the idea. Berg already had experience working with the then novel aluminium, and was to later manufacture components for Zeppelin's first airship. With financial and technical help from Berg and his firm, the airship was designed and built.

Construction began in 1895 at the Tempelhof field in Berlin. For a time the Prussian Airship Battalion placed its grounds and personnel at Schwarz's disposal. The components were produced in Carl Berg's Eveking Westphalia factory and, under the direction of Schwarz, assembled in Berlin. A gondola, also of aluminium, was fixed to the framework. Attached to the gondola was a Daimler engine that drove aluminium propellers. One of the propellers was used to steer the craft.

Death and maiden flight

Schwarz did not live to see his airship fly. Between 1892 and 1896 he traveled frequently, which affected his health. Shortly before his death he received news that his airship was ready to be filled with gas. On 13 January 1897 he collapsed outside the "Zur Linde" restaurant in Vienna, and died minutes later from heart failure, aged 44. Historical sources speak of a blutsturz (a term meaning either hemoptysis or hematemesis).

Carl Berg required confirmation of Schwarz's death, suspecting he had fled to sell his secrets. Nevertheless, Berg resumed the work with Melanie, Schwarz's widow, and together with the Airship Battalion they completed the airship with the addition of a gas relief valve.

This second airship had these specifications: Volume: Length: Diameter: Engine: Daimler Four propellers: one of diameter between the gongal and the envelope, two of diameter mounted on brackets either side of the envelope, and a fourth of diameter revolving in the horizontal plane mounted below the gondola to drive the craft up or down. Envelope: 0.2 mm aluminium plates riveted to framework.

A later structural analysis based on the drawings concluded that it was defective, with the skin taking most of the shear stresses: distortions of the skin can be seen in a photo of the craft in flight.

The second airship was tested with partial success at Tempelhof near Berlin, Germany, on 3 November 1897. Airship Battalion mechanic Ernst Jägels

Robinson, Douglas H. Giants in the Sky: History of the Rigid Airship. Henley-on-Thames, UK: Foulis, 1973. .