This was really a hard job, friends, because concentrated information is not available. This is what I compile from requests on several forums. It should have been ready before Christmas, but then I got interrupted. Hope you like to read about
The Caproni Ca.335 / SABCA S. 47
Caproni, Italian bomber king of WWI, but not very spoiled with orders from Mussolini's Regia Aeronautica (my opinion, RT) tried around 1937 to exceed his business. In this time we see not only the selling of the Caproni-Bergamaschi Ca.135 medium bomber to Hungary and Peru (!!, RT), but also activities to sell the Ca.135 and the multi-purpose airplane Ca.310 to Belgium. The Belgian firm SABCA acquired the licence to sell these two planes. The Belgian Air Force, at that time, was still running the old Fairey Fox two-seat light bomber biplane, but looking to replace it with a modern design. Although Fairey had a strong foothold in Belgium in form of an own plant (Aviations Fairey), SABCA and Caproni in 1938 made a new agreement to develop a competitor to the contemporary Fairey design Battle (although a strong formal resemblance between the Ca.335 and the Battle is obvious, unfair copying cannot be proved. The Battle had its maiden flight already in 1936, so its look should have been known to the responsible persons, and the design should have followed the requirements of the Belgian Air Force for a new two-seat light bomber. The also similar Fulmar did not fly before 1940, RT).
Caproni got obliged with the construction of the airframe, while SABCA had to care for engine, propeller and armament, and so the Ca.335, called "Maestrale" (northwest wind, in French "Mistral"), was drafted by Caproni chief engineer Cesare Pallavicino. His performance is interesting by the way, he designed some particular aircrafts: Breda 15/18/19/27/33/39, CAB A.P.1/C.P.3/P.L.3/P.S.1, Caproni Ca.135/Ca.308/Ca.309, after the Ca.335 the Ca.331 and Ca.355. After the war he designed the famous scooter "Lambretta", before going to Argentina, where he created the I.Ae.30 "Namcu", a very fast two-engined fighter similar to the De Havilland "Hornet".
Pallavicino chose a clear cantilever low-wing design for a crew of two. The observer/rear gunner, sitting under a "greenhouse" glass roof in the rear fuselage, could also perform as auxiliary pilot, having a set of controls of his own. The construction contained of steel tubes, the fuselage was covered with aluminium plates, the wing with plywood. The whole back edge of the wing was covered with flaps, thus caring for short landing distances.
For to drive the aircraft, the French Hispano-Suiza HS 12Y twelve-cylinder V-engine was provided (we already know it from the Arsenal fighters, RT), delivering 860 hp and allowing to install a 20mm cannon firing through the propeller hub. Armament was completed by two wing-mounted 7,7 mm machine guns and a flexible one for the second crew member. A small bomb bay could carry two 50 kg bombs, while ten 10 kg bombs were to be mounted externally.
From the beginning, the aircraft was designed to serve as fighter, light bomber or reconnoisater (a very modern layout, you can compare it with modern combat aircraft, RT). The airplane was completed at Caproni's factory in Ponte San Pietro and flew for the first time on February 16th, 1939, with test pilot Ettore Wengi on the controls. In June that year, it became dismantled and sent by train to SABCA in Belgium. The next month, it is exhibited at the Salon International de Bruxelles.
After fitting the missing equipment, the flight tests continue in Belgium under the civil registration OO-ATH from September 19th on, with SABCA's chief test pilot Paul Burniat at the controls. With a speed of 501 (other source says even 515) kph and a ceiling of 10.500 m, the aircraft showed very fine performances. Nothing negative is said about the flight characteristics, so it can be assumed that the tests ran smoothly. On January 13th, it is demonstrated at Evère to the Belgian Aèronautique Militaire. The responsibles were quite delighted and told an option for 24 samples to be produced. On this occasion or another, the S.47 was also shown to foreign military delegations.
SABCA had purchased the manufacturing licence on November 30th, 1939. On March 14th, 1940, the S.47 was flown together with the SABCA S.40 training aircraft to Orleans-Bricy (the French test center we know already, RT), to be presented to officers of the French Armèe de l'Air. There, because of bad weather conditions, the aircraft is slightly damaged in a landing accident, when it collided with a truck.
Neither in Belgium nor in France, anything could have been done to set up a production of the S.47 before the German troops arrived. In Orleans, the never-repaired S.47 fell in German hands on June 13th, 1940. Caproni made a request to get the airplane back, but the Germans (nobody can say who exactly or why) turned it down. The final fate of the prototype is unsure, one contributor says it was still seen in Orleans in April 1942, the other says mid-1943. Probably it was scrapped there, it was surely not brought to Germany.
One can say in mid-1940, the Regia Aeronautica had no interest in the type and did not support Caproni's request. My personal remarks: At this stage of war, the European Axis countries still thought about a short and victorious war and did not care much to improve their flying equipment. Also, the Ca.335 followed Belgian requirements, not Italian ones. Another difficulty surely was caused by the French inline engine, while Italy had nothing of its own to replace it and deliveries from defeated France were unsure or at least politically unwished. When Italy, some months later when the desert war had started, badly needed something to replace the weakly performing Breda Ba. 65 (and never got something appropriate), the chance was over. Applying some armour, the "Maestrale" could have formed an Italian "Shturmovik", or, with foldable wings, would have been a nice equipment for the Italian carrier "Aquila"! But, gone with the (northwest) wind!
My thanks to:
"Ghibli" on airwarfareforum.com
Charles Mali and Luc Vanden Eynde on baha.be.
Construction details from www.eichhorn.ws (there in German language)
"Ghibli" tells 'Dimensione cielo n°2', ed. Bizzarri 1971, and the article 'Quand les démocraties occidentales achetaient des avions dans l'Italie fasciste... 2ème partie', from Avions n°72 1999, as his sources. Charles Mali says being writer himself, his book is called "Les avions SABCA et associés Prototypes et projets".
[08/07/2013 sorry being unable to retrieve the original picture sequence. But got new ones today, see below].
One picture in Belgian colours: