J.Davilla, A.Soltan French Aircraft of the First World War (Flying Machines)

Gourdou-Leseurre C1 and 2 C1

  C. Edouard P. Gourdou and Jean A. Leseurre were aeronautical engineers who patented an aerofoil shape intended to reduce aircraft drag in January 1917. An official document shows that in the summer of 1917 a monoplane designed by Gourdou and Leseurre was built at the Wassmer carpentry works in Paris. It featured the new wing that Gourdou and Leseurre had patented (brevet no.504302). The plane appeared in the fall of 1917 and shortly thereafter testing began at Villacoublay. Powered by a 180-hp Hispano-Suiza engine, it attained a maximum speed of 223 km/h. Testing was suspended by December 1917, and the plane underwent a series of apparently minor alterations. The modified design, designated the GLa, retained the 180-hp Hispano-Suiza engine. It was submitted to the STAe to meet the C1 specification for a single-seat fighter with a payload of 110-170 kg, maximum ceiling of 9,000 km, a service ceiling of 6,500 m, and a maximum speed of 140 km/h. Other aircraft designed to meet the C1 category and powered with the 180-hp Hispano-Suiza 8 Ab engine included the Laboratoire Eiffel monoplane.
  The Gourdou-Leseurre GLa first appeared in early 1918 and was also built by Societe Wassmer. The fuselage was of steel tubing while the engine mounts were constructed of duralumin. The undercarriage struts were made of steel tubing and a conformal fuel tank, which could be jettisoned, was fitted between the landing legs. The Hispano-Suiza 8Ab engine was fully cowled with large covers over the rocker arms. The monoplane wing was suspended by a combination of center section struts and two faired steel struts extending from each side of the fuselage. The wing spars were of steel, the ribs were wooden, and the entire structure was covered in fabric except for the leading edges, which were covered with plywood. This version of the Gourdou-Leseurre fighter had a fixed tailplane. The GLa received the STAe designation Gourdou-Leseurre C1.
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G-L C1 Single-Seat Fighter with 180-hp Hispano-Suiza 8Ab
   Span 9.0 m; length 6.6 m; height 2.3 m; wing area 16.65 sq. m
   Empty weight 600 kg; loaded weight 786 kg
   Maximum speed:
1.000 m 242 km/h
2.000 m 237 km/h
3,000 m 230 km/h
4,000 m 223 km/h
5,000 m 214 km/h
   Climb:
1000 m 2 min 25 sec
2000 m 5 min 16 sec
5000 m 8 min 43 sec
4000 m 12 min 44 sec
5000 m 20 min 10 sec
   Ceiling 6000m; endurance 1.5 hours.
   One built