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Open Source Philosophy and the Dawn of Aviation

In 1883, the brothers Albert and Gaston Tissandier from France designed and constructed the first airship powered by electricity. The current was supplied by 24 potash cells to a Siemens 1.5 hp (1.1 kW) engine running at 180 revolutions per minute, The engine drove a large two-bladed pusher propeller, through a reduction gearbox. The speed achieved at no wind conditions was still only 4.8 km/h, since the ratio of power to weight was no better than that of Giffard’s airship (Santos-Dumont, 1904).

Charles Renard and Arthur Krebs, military officers in the French Army Corps of Engineers, built an elongated airship, La France (Fig. 3), which was a vast improvement over earlier models in 1884. La France was the first airship that could return to its starting point in a light wind. It was 50.3 m long, its maximum diameter was 8.2 m, and it had a capacity of 1,869 m³. Like the Tissandiers’ airship, a 7.5-hp (5.6 kW) electric, battery-powered motor propelled La France. This motor was later replaced with another one that delivered 8.5 hp (6.3 KW). A long and slender car consisting of a silk-covered bamboo framework, lined with canvas hung below the balloon. The structure that accommodated the batteries and engine was 33 m long, 1.4 m wide, and 1.8 m deep. The engine drove a four-bladed wooden tractor propeller that was 7m in diameter, but which could be inclined upwards when but which could be inclined upwards when landing to avoid damages to the blades. Renard also provided rudder and elevator, ballonets (to keep the shape of the gas container), sliding weight to compensate for any shift in the gravity center, and a heavy guide rope to assist in landing, all this would become standard equipment for the next generations of airships to come.

The first flight of La France took place on August 9, 1884. Renard and Krebs landed successfully at the spot where they had begun — a flight of only 8 km and 23 minutes, however one during which they had been in control throughout. In 1884 and 1885, La France made seven flights. Although its batteries limited its flying range, it was demonstrated that controlled flight was possible if the airship had a sufficiently powerful lightweight engine.

The first airship equipped with a petrol engine was built by Karl Wölfert, in Germany (Fig, 3). In 1896, he constructed an airship pointedly named Deutschland. The gondola was directly connected to the hull and an 8-hp Daimler engine powered the aircraft, which flew for the first time on August 10, 1898 in Cannstatt, close to the city of Stuttgart. In 1897, the airship caught fire during a flight in Tempelhof, in Germany. Wölfert and his mechanic died in the accident. Escaping hydrogen from the envelope had probably come into contact with the hot exhaust gases from the engine. They were the first victims of J. Aerosp. Technol. Manag., São José dos Campos, Vol.4, No 3, pp. 355-379, Jul.-Sep., 2012 361