the experimental first ship flying in 1907. It had a rigid keel under the envelope. Four more military airships of this design were built, and often rebuilt, designated M I to M IV, up to 1914. The most advanced construction of semi-rigid airships between the two World Wars took place in Italy. There, the state-factory Stabilimento di Costruzioni Aeronautiche (SCA) constructed several. Umberto Nobile, later General and director, was its most well-known member, and he designed and flew several semi-rigid airships, including the Norge and Italia, for his overflights of the North Pole, and the W6 OSOAVIAKhIM, for the Soviet Union's airship program. List of other semi-rigid airships Pre-War and WWI Bartolomeu de Gusmão from Augusto Severo de Albuquerque Maranhão in Brazil in 1894, destroyed in March 1894 by a gust of wind Pax from Augusto Severo de Albuquerque Maranhão in France in 1902, caught fire at its first ascent, killing the pilot Le Jaune - Built by Lebaudy Frères in France, first flight: 1902-11-13. Lebaudy built many other semi-rigid airships, among them the Patrie and the République. Forlanini F.1 Leonardo da Vinci, Italy, 3265 m3, 40 PS, first ascent: 1909; 1910-02-01 damaged beyond repair The Groß-Basenach-type airship (5 built for the Prussian army) The Luftschiff von Veeh (also Veeh 1 or Stahlluftschiff) built by Albert Paul Veeh from Apolda in Düsseldorf in the 1910s Siemens-Schuckert I (1911), M.1, Italian, first flight 1912, 83-metre long, 17-metre diameter, 2× 250 PS Fiat SA.76-4 engines each with one airscrew, payload: 3800 kg, first with the Army then the Navy, 164 flights, decommissioned 1924 M.2, Città di Ferrara, Italian, first flight 1913, hull identical to the M.1, 83-metre long, 17-metre diameter, 4×125 PS driving two airscrews, payload 3000 kg, speed: 85 km/h, a Navy airship, stationed in Jesi, on 1915-06-08 shot down by an Austrian flying boat Forlanini F.2 Città di Milano, Italy, 11,500 m3, 2×85 PS, first flight: 1913-04-09, destroyed 1914-04-09 at Como SR.1 (M-class) built by Italy for England 1918, 12,500 m3, 83 m long, 17 m Diameter, 9-man crew, internal keel of triangular steel components 1920s and 1930s Among the Parseval airships designed by August von Parseval in the 1900s-1930s: PL 26 and PL 27 Parseval-Naatz designs Zodiac V10 was built 1930 for the French Navy O-1 (airship) built by SCDA, Italy, and the only true semi-rigid airship to serve with United States Navy. RS-1 was the only semi-rigid American