SPAD S-VII
With the aircraft of the SPAD-series, the airplanes of World War I achieved their highest technical achievement to date. The models S. VII and its successor version S. XIII were regarded as the best fighter aircrafts of the war.
They were designed by Louis Béchéreau who had constructed the fastest racing airplanes in the world in 1912 and 1913. Partial credit for the success of the SPADs goes to Marc Birkigt, chief engineer of the engine factory Hispano Suiza, who had constructed a new 8 cylinder V-engine which surpassed the rotation engines which were formerly being used. Béchéreau constructed his design principally around the new engine type.
The initial flight of the SPAD S.VII took place in April 1916. The prototype, though equipped with the not yet power enhanced 140 PS engine, still achieved a speed of 196 km/h and climbed to an altitude of 3,000 m in 15 minutes. With a strong 150 PS engine, the S.VII set a record for the most improved rate of climb of 2,000 meters in 6 min and was the first fighter to achieve an hourly speed of over 200 km/h.
Series production immediately began after this convincing initial flight due to the fact that the French authorities had already ordered 268 copies. There was also a plentitude of export and license orders from foreign countries.
By September 1916, approximately 500 aircrafts of the first version with a 150 PS-(117 kW) strong Hispano Suiza 8Aa were delivered. The second series version was equipped with a performance-powered 180 PS-(134 kW) Hispano Suiza 8Ac engine and wider wing span from SPAD and various orderers constructed over 6,000 copies. A total of approximately 5,600 copies from both series were constructed in France alone.
The SPAD S.VII was utilized in all French and American squadrons, as well in in eleven Italian and one Belgian squadron. 43 S.VII aircrafts were also used in Russia. In 1917, it was replaced by the S.XIII which was faster and possessed more efficient armament. Aircrafts of this model were supplied to Peru, Portugal, Brazil, Greece, Romania, Yugoslavia and Siam.
The S.VII was fast and stable for the time and was regarded as well-designed. Its stability provided for good nose dive capabilities. Nevertheless, it was reported that it was not very versatile which also was due to the limited frontal and rear view of the pilot.
The S.VII originated from a one-seater biplane S.V with train propeller that took off for the first time by the end of 1915. The construction was made out of wood. The rear was covered with fabric and the frontal fuselage area was cased in aluminum. The engine was protected by a metal hood that enclosed an Eight-Cylinder V engine with a round frontal radiator. The apparent dual-longeroned wings were bound and braced through auxiliary longerons, so in reality, the S.VII was a single-longeron aircraft. The rigid chassis had a tail wheel. The armament consisted of a Vickers-Standard machine rifle from Birkigt who also had designed the V-engine.
The most famous French pilots of the time as well as Georges Guynemer flew the S.VII. After World War I, it was utilized in the civil sector and often for training purposes.
Technical data
SPAD VII
| Manufacturer | SPAD | |
| Power plant |
first series: an air-cooled V-8 Hispano-Suiza 8Aa engine with 150 PS (110.3 kW) second series: a V inline-engine Hispano-Suiza 8Ac with 180 PS (134 kW) | |
| Year of construction | 1916 |
Performance
| Top Speed |
up to 212 km/h normally 190 km/h |
| Rate of climb | to an altitude of 2,000 m in 6 min. |
| Service altitude | 5,500 m |
| Flight duration | 2 h 15 min. |
Weight
| Empty weight | 545 | kg |
| Max. take-off weight | 755 | kg |
Dimensions
| Span | 7.82 | m |
| Length | 6.19 | m |
| Height | 2.33 | m |
| Wing span area | 18,5 | m2 |
| Crew | 1 person | |
| Useful load/armament | a forward-shooting, synchronized 7.7-mm-Vickers MG |
