Blériot-SPAD S.61

The Blériot-SPAD S.61 was a French fighter aircraft developed in 1923. Designed by André Herbémont, the S.61 was a conventional biplane, abandoning the swept upper wing used by Herbémont in several previous designs. The prototype S.61 was evaluated by the French Air Force alongside the S.51 as a potential new fighter, but like its stablemate, was rejected. The Polish Air Force (which had also purchased the S.51) was impressed enough to order 250, as well as purchase licences for local production. The Romanian Air Force also ordered 100 aircraft. About 30 were built in Poland, by the CWL (Centralne Warszaty Lotnicze - Central Aviation Workshops, a predecessor of PZL).

Operational history
Apart from their military service, S.61s were used in France for racing and record-setting attempts. On 25 June 1925, Pelletier d'Oisy won the cross-country Coupe Michelin in an S.61, and another of the type won the 1927 race and was placed second in the 1929 race. An S.61 was also used by Jean Callizo in his fraudulent attempt on the world altitude record that saw him stripped of his Légion d'Honneur. A Polish S.61 placed second in the Capitaine Echard race at the Zürich aerial meeting in 1927.

The S.61 (known in Poland simply as Spad S.61) had a poor reputation in Poland due to numerous crashes, many attributed to a weak wing mounting. During the period from 1926 to 1931, 26 pilots were killed while flying the S.61.

Variants

 * S.61/1:prototype for French evaluation, powered by a 430 hp Lorraine-Dietrich 12Ew W-12 engine with supplementary supercharger.


 * S.61/2:production version for Poland and Romania, powered by a 450 hp Lorraine-Dietrich 12Ew W-12 engine with supplementary supercharger.


 * S.61bis:converted S.61/2, powered by a 430 hp Lorraine-Dietrich 12Ew W-12 engine with supplementary supercharger.


 * S.61/3:single machine with reduced wingspan, powered by a 430 hp Lorraine-Dietrich 12Ew W-12 engine with supplementary supercharger.


 * S.61/4:single machine with a 480 hp Lorraine-Dietrich 12Ee W-12 engine


 * S.61/5:three machines with a 450 hp Hispano-Suiza 12Gb W-12 engine


 * S.61/6:racer prototype converted from the S.61bis, powered by a 430 hp Lorraine-Dietrich 12Ew W-12 engine with supplementary supercharger.


 * S.61/6a:single racer


 * S.61/6b:The S.61/6a converted with extra fuel tankage for the 1924 Coupe Michelin race


 * S.61/6c:single aircraft built to contest world airspeed record; destroyed in the attempt


 * S.61/6d:single aircraft built for unsuccessful attempt on world airspeed record


 * S.61/7:Powered by a 450 hp Lorraine-Dietrich 12Eb W-12 engine, with Rateau supercharger for world altitude record attempt


 * S.61/8:A single S.61/5 refitted with a 500 hp Hispano-Suiza 12Hb V-12 engine.


 * S.61/9:single S.61/6d modified for 1929 Coupe Michelin race, powered by a 230 hp Lorraine 7Ma Mizar radial engine.


 * S.61 Ses: (Ses for Sesquiplane) This was the final version of the Bleriot S.61, fitted with seaquiplane wings, powered by a 450 hp Lorraine-Dietrich 12Eb W-12 engine. (1 built).

Operators

 * Polish Air Force
 * 2nd Fighter Regiment
 * 3rd Fighter Regiment
 * 4th Fighter Regiment
 * 11th Fighter Regiment
 * 11th Fighter Regiment


 * 🇷🇴 Romania
 * Royal Romanian Air Force


 * Soviet Air Force - One aircraft, used for tests and trials.
 * Soviet Air Force - One aircraft, used for tests and trials.