Spad 13.C1 (Windsock Datafiles 32)
By J. M. Bruce
Publisher: Albatros Productions Limited 1996 39 Pages
PDF 22 MB
The Spad HS had first flown in April 1916; its production, as the Spad 7.C1, was ordered in May, and it began to enter operational service in the French escadrilles de chasse in August. A specimen was delivered to the RFC on September 9 1916. One of the most successful pilots of the Spad 7 was Georges Guynemer: flying his first Spad, S.113, he scored his 15th victory on September 4 and two further, but unconfirmed, victories on September 9.
Guynemer was delighted with the Spad, and recorded ten more confirmed victories by the end of 1916. By then, however, the intensity of aerial combat had increased markedly, and the Spad was opposed by more advanced German fighters armed with twin fixed, forward-firing machine guns. In December 1916, Guynemer wrote to Louis Bechereau, the designer of the Spad:
'The 150-hp Spad is not a match for the Halherstadt. Although the Halherstadt is probably no faster it climbs better, consequently it has the overall advantage. More speed is needed: possibly the airscrew might be improved'
A measure of relief was obtained by fitting the 180-hp Hispano-Suiza 8Ab engine, a modification of the basic direct-drive engine with increased compression ratio; but the Spad 7 remained a single-gun fighter, at a combat disadvantage when matched against contemporary twin-gun German aircraft.
By the end of June 1916 the Hispano-Suiza company had completed three examples of a geared development of its V-8 engine, one of which had successfully completed an official 50-hour test run on June 11. This engine, in its production form, delivered 208 bhp at 2000 rpm at ground level, and at maximum permissible rpm of 2100 gave 215 bhp. With the basic type number 8B this was generally known as the 200-hp Hispano-Suiza.