During early 1917, the French designer Louis Béchereau, spurred by the approaching obsolescence of the S.VII, decided to develop two new fighter aircraft, the S.XII and the S.XIII, both using a powerful new geared version of the successful Hispano-Suiza 8A engine.

The cannon armament of the S.XII was unpopular, but the S.XIII proved to be one of the most capable fighters of the war, as well as one of the most-produced, with 8,472 built and orders for around 10,000 more cancelled at the Armistice.

In addition, the United States Army Air Service also procured the type in bulk during the conflict, and some replaced or supplemented S.VIIs in the Royal Flying Corps (RFC), pending the arrival of Sopwith Dolphins.

[4] More capable German fighters soon resulted in a shift in aerial supremacy towards the Central Powers, which led to calls for better aircraft.

However, this aircraft only saw limited use, having been rapidly followed into production by the more conventionally armed S.XIII, which was deemed to be a preferable configuration by several French pilots and officials.

Andrews has claimed that a large portion of the credit for the S.XIII lies with Marc Birkigt, the designer of the engine, who had chosen to introduce various innovative features upon it, such as monobloc aluminium cylinders, which were furnished with screwed-in steel liners, which improved its performance.

In terms of its construction, it shared a similar configuration and layout to the earlier S.VII,[nb 1] featuring a mainly wooden structure with a fabric covering.

Other changes were made to the ailerons, the rounded tips of the tailplanes, the bulkier cowling accommodating the gear-drive Hispano-Suiza 8B engine, and enlarged fin and rudder with a curved trailing edge.

[15] Similar pumps were used for supplying pressurised oil and water circulation between the engine's radiator and a header tank was housed within the upper wing.

[12] The upper wing was made in one piece, with hollow box-section short spars that connected with linen-wrapped scarf joints, Andrews claims that long runs of spruce were difficult to obtain.

[11] It was faster than its main contemporaries, the British Sopwith Camel and the German Fokker D.VII, and its higher power-to-weight ratio gave it a good rate of climb.

Even in April 1918, an official report stated that two-thirds of the 150 kW (200 hp) SPADs were out of use at any one time due to engine problems.

[25] At the end of the war, plans were underway to replace the S.XIII with several fighter types powered by the 220 kW (300 hp) Hispano-Suiza 8F, such as the Nieuport-Delage NiD 29, the SPAD S.XX and the Sopwith Dolphin II.

[26] These plans lapsed following the signing of the Armistice of 11 November 1918, which ended the First World War and the SPAD S.XIII remained in French service as a fighter aircraft until 1923,[16] with Nieuport-Delage NiD 29 deliveries being delayed until 1920.

[28] Other Allied forces were quick to adopt the new fighter as well and the SPAD XIII equipped 15 of the 16 operational USAAS pursuit squadrons by the Armistice.

In the United States, some S.XIIIs were re-engined with 130 kW (170 hp) Wright-Hispano engines and used to prepare pilots for the new Thomas-Morse MB-3 fighter (which used SPAD-type wings) in 1922.

[29] During December 1917, No.23 Squadron Royal Flying Corps (RFC) equipped with the SPAD S.XIII and retaining them until April 1918 when it re-equipped with the Dolphin, while No.