June, 1933 AIRCRAF T ENGINEERING 129 Details of the Italian Macchi Castoldi Seaplane and Fiat Engine Fro m R. Giacomelli N April 10 Warrant-Officer Francesco Agello of the Italian Air Force set up a new speed record of 682-403 k.p.h. (424 m.p.h.)* over a 3-kilometre course at Lake Garda in a Macchi Castoldi 72 seaplane with a 2,500-h.p. Fiat A.S.6 engine. Details of the Attempt Five runs were made over the course, the speed obtained on each being as follows:— First run : 678∙477 k.p.h. (421∙6 m.p.h.) Second run : 682∙637 k.p.h. (424∙2 m.p.h.) Third run : 674∙662 k.p.h. (419∙2 m.p.h.) Fourth run : 692∙529 k.p.h. (430∙3 m.p.h.) Fifth run : 675∙971 k.p.h. (420 m.p.h.) This beat the previous, British, record of (555 k.p.h. (407∙5 m.p.h.) set up by Flight- Lieutenant H. G. Stainforth over the Solent on September 29, 1931, in a Supermarine S.6B seaplane with a 2,300 h.p. Rolls-Royce R. engine. The new record is the result of long and LEADIN G PARTICULARS OP THE SEAPLANE searching preparation. In 1929 the Air Trophy race, was discovered, however, which .. .. .. .. Tar e weight 2,500 k.g . (5,510 lb.) Minister, General Balbo, convinced of the essen proved impossible t o eliminate, in spite of all the Pilo t .. .. .. .. .. .. 70 kg . (154 lb.) tial importance of high-speed contests for the efforts made during the two months available Petro l .. .. .. .. .. .. 420 kg . (926 lb.) Oil . . .. .. .. .. .. .. 3 5 kg. (77 lb.) technical improvement of aeroplanes and for the tests, which comprised thirty-five flights. Gros s Weight .. .. .. .. .. 3,025 kg. (6,6637 lb.) engines, starte d a special school for training a The engine was subsequently removed to under Win g are a .. .. .. .. 15 sq . 111. (162 sq . ft.) restricted number of pilots in the handling of Win g loadin g .. .. .. 202 kg./sq . in . (4llb./sq . ft.) go bench tests, and it was not until April 1932, Rate d horse-power .. .. .. .. 2,500 h.p . racing aircraft. The Italian High Speed Flight tha t it was passed as fit for flight. Tests then Power loadin g .. .. .. .. 1∙2 kg./h.p . (2∙6 lb./h.p. ) was thu s brough t int o being a t Desenzano on Lake Weight of engine .. .. .. .. 945 kg . (2,083 lb.) showed that the power had been raised from Garda, an ideal location as th e lake is sufficiently 2,300 h.p. to 2,500-2,600 h.p., and even to borate in producing suitable seaplanes. Un large to offer equal facilities with the open sea, 2,850 h.p. High speed tests were then carried fortunately the machines reached Descnzano while it has none of its drawbacks as regards out, speeds of 650 k.p.h. (404 m.p.h.) and for the tests much later tha n the specified date, corrosion and comparatively sheltered condi 680 k.p.h. (422∙5 m.p.h.) and, in one attempt, the many difficulties cropping up during the tions can be counted upon. of 710 k.p.h. (441∙1 m.p.h.), being reached preparation of a racing aeroplane and engine successively. In view of these results the Air having been the cause of unforeseen delays. Th e High-Speed Flight Minister gave permission for an attempt to be For the following race, in 1931, the earlier made on the record with the machine used in The first course was started with eleven practice of seeking the collaboration only of these tests instead of waiting for the aeroplane pilots, chosen after a rigorous selection. Eight specialised firms, Macchi for the aeroplane and which was being specially built for the attempt, months later, seven of these, on the same day, Fia t for the engine, was reverted to. which has higher power and lower drag. Ex flew the fastest aeroplane of the time, making pectations were justified, as on the officially a speed of 510 k.p.h. (317 m.p.h.). Simulta Th e M.C. 72's Trials timed test on April 10 a speed of 682∙403 k.p.h. neously, preparations for the 1929 Schneider (424 m.p.h.) was recorded. Routine training was restarte d at Descnzano, Trophy Race were in progress, and the Govern and the Macchi firm worked on their seaplane ment thought it advisable to invite all th e lead The High Speed Flight is under the com racer the M.C.72, which incorporated note ing Italian aeroplane and engine firms to colla- man d of Col. Dr.-Ing. Bernasconi, to whom the worthy new characteristics, especially in the results achieved are in a great measure due. engine and airscrew system. The first flights * The average of the first four runs, which are presumably those with this seaplane took place in June, 1931, used in arriving at the claimed record actually work out at speeds of over 600 k.p.h. (373 m.p.h.) being 682∙076 k.p.h. but 682∙403 k.p.h. is the figure officially issued by Details of the Seaplane the Italian authorities. The reason for the slight discrepancy is not reached. A defect in the engine, sufficiently clear, as the detailed figures of the five runs come from the sure The Macchi M.C.72, designed by Signor Mario grave to preventparticipation in the Schneider source.—EDITOR. Castoldi, is a low-wing monoplane, the plane of which is braced by streamline wires of special steel. The plane has a bi-convex, symmetrical section and is made entirely of duralumin, the whole of the surface being covered with fiat tub e radiators. Metal is used for the forward and centre portions of the fuselage, and wood for the tail. The engine unit occupies a considerable portion of the length of the fuselage. It is carried on a special mounting on which are also mounted the float struts and the two wings. The float chassis is of mixed wood and duralu min construction, the upper surfaces being almost entirely covered with radiators for the cooling water and oil systems. The floats and tai l surfaces are of normal construction.
Aircraft Engineering and Aerospace Technology – Emerald Publishing
Published: Jun 1, 1933