Jeanson-Colliex

   If the amount of information about this monstrous double biplane flyingboat is in proportion to its size, it is not because the aircraft was successful. It was well publicized in aviation journals, even at the end of 1914, a time of secrecy and censorship; but then as now some of the most publicized designs were the least successful.
   Maurice Colliex began as a draftsman for the Voisin company, and became a friend and collaborator of Gabriel Voisin. He started the construction of this aeroplane in mid-1912: one might wonder at its similarities to another giant machine, the Icare, built by Voisin. The Jeanson-Colliex was built around a large hull shaped like a speedboat, built by the boat-builder Despujols, with a cut-off stern and a step midway back. Inside the hull, designed to accommodate 10 people or the corresponding weight of armament, were mounted side-by-side 2 200 hp 6-cylinder inline water-cooled Chenus, which together through a reduction gear and concealed chains or shafts drove a single 5-meter diameter 2-blade pusher propeller.
   The high-aspect-ratio wings were arranged in 2 biplane cells: the main set was mounted over the sternpost, fixed on booms; and the forward set was braced like a set of jibs from a bowsprit. Ailerons were fitted only to the top rear wing. The elevator and twin rudders were mounted behind the rear cell; wingtip floats were set under the lower rear wings.
   The flyingboat was launched on the Seine at Triel, upstream from Meulan, west of Paris, in 1913; it was demonstrated in 1914 in front of the Commission de Securite at Triel. It is reported to have made "some flights" between Triel and Vaulx-sur-Seine (Meulan), where the river is straight for almost 4 km. Other sources report earlier flights of 10 km between these same places, but these seem unlikely, and were probably taxiing trials up and down the river from Triel. Photos dated February 1914 show several modifications: 3 rudders, shorter struts for the wing floats, longer spans for both sets of wings, a more streamlined fairing added to the stern.
   This version was photographed taxiing at high speed, pushing a big foaming bow wave. And one photograph shows it in flight.

   (Span: rear set, 24 m, with rows of 7 and 9 interplane struts; increased to 27 m (rows of 9 and 11 struts); wing area, longer span: 145 sqm; length overall: 16 m; length of hull: 7.7 m increased to 8.6 m; hull width: 2.6 m; empty weight: c 3700 kg; gross weight (2 pilots, 2 mechanics, fuel for a 13 hr flight to maximum range of c 1500 km): 4300 kg; 2 200 hp Chenus)