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

Gourdou-Leseurre C1 and 2 C1

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  The prototype was heavier than expected and in order to meet the C1 payload specifications the aircraft's structure had to he considerably lightened. As a result ol the weight reduction program, the Gourdou-Leseurre C1 was an excellent performer and was faster than any of the other C1 aircraft equipped with the same engine. The STAe pilot’s report states the GLa was easy to fly, maneuverable, and offered the pilot an excellent field of vision. However, there were problems. The wing support structure was fell to be too weak and the aircraft was substantially revised to incorporate a more extensive array of wing braces. The wing was modified with an increase in span to 9.4 nt and elimination of dihedral; in addition, the tail was modified, the fin was reduced in size, and a new rudder was installed. The landing gear struts were revised to handle the increased weight of the aircraft and to permit the belly fuel tank to be jettisoned without difficulty. These changes were extensive enough to warrant the new designation GLb, while the STAe redesignated the aircraft the Gourdou-Leseurre 2 C1. The improved wing bracing enabled the wings to withstand a load factor of ten. Armament was two Vickers 7.7-mm machine guns.
  Twenty ol these revised aircraft were ordered by the Aviation Militaire. The first was tested at Villacoublay in November 1918. The results revealed a good performance, but the fin and rudder were subsequently enlarged. It is possible that one aircraft was tested with a 230-hp Salmson 9Za; a Le Rhone 9K may also have been fitted. It was also planned to equip one aircraft with the 320-hp A.B.C. Dragonfly engine, but this was probably never done.
  The end of the war meant that there was no further need for the Gourdou-Leseurre 2 C1 and plans to produce it for the Aviation Militaire and the United States Air Service were terminated. One example was sold to the Finnish air service in 1923, and 18 more were sent in 1924. One additional aircraft was later assembled from spares. Serial numbers were 8 E 2 and 8 F 5 through 22 (8 F 14 was used twice). Codes were later modified to become GL 5 through 22. These aircraft served with the Havittajaeskaaderi (First Fighter Squadron) commanded by Captain E. Koni at Utti. The aircraft were withdrawn from service by 1933. Postwar, the Gourdou-Leseurre factory was established at Saint-Maur-des-Fausses.


G-L 2 C1 Single-Seat Fighter with 180-hp Hispano- Suiza 8Ab
   Span 9.4 m; length 6.45 m; wing area 18.8 sq. tn
   Empty weight 570 kg; loaded weight 850 kg
   Maximum speed: 245 km/h at ground level; 220 km/h al 5.000 m, climb to 5000 m in 17 min 50 sec; ceiling 7500 m
   Armament: two Vickers 7.7-mm machine guns
   Approximately 20 built