The Asso XI was a family of water-cooled,

supercharged In an internal combustion engine, a supercharger compresses the intake gas, forcing more air into the engine in order to produce more power for a given displacement. The current categorisation is that a supercharger is a form of forced induct ...

V12 V12 or V-12 may refer to: Aircraft * Mil V-12, a Soviet heavy lift helicopter * Pilatus OV-12, a planned American military utility aircraft * Rockwell XFV-12, an American experimental aircraft project * Škoda-Kauba V12, a Czechoslovak experim ...

piston aeroengines produced in the 1930s by Italian manufacturer Isotta Fraschini, and fitted on a number of aircraft types built by CANT, Caproni and others.

Design and development

Isotta Fraschini produced a long series of engines with the name Asso (Ace, in English). The Asso XI R.C. was an upright, liquid-cooled V-12 engine with maximum power output in the range depending on the degree of supercharging. There were two variants, differing only in their supercharger speed: the R.C.40 ran at a little over 10 times the crankshaft speed and enabled the engine to maintain a

rated power In electrical engineering and mechanical engineering, the power rating of equipment is the highest power input allowed to flow through particular equipment. According to the particular discipline, the term ''power'' may refer to electrical or m ...

of to an altitude of whereas the R.2C.15 held to with a supercharger gearing of 7. All variants of the R.C.40 had much in common with construction of the earlier Asso 750 R.C., though they had two, rather than three, banks of 6 cylinders and 4 rather than 2 valves per cylinder. Cylinder barrels were machined from

carbon steel Carbon steel is a steel with carbon content from about 0.05 up to 2.1 percent by weight. The definition of carbon steel from the American Iron and Steel Institute (AISI) states: * no minimum content is specified or required for chromium, cobalt ...

with flat-topped heads and valve seats. Each barrel had a separate sheet steel water jacket. Cast aluminium head blocks were bolted to each of the two banks of 6 cylinders, providing valve ports, guides, coolant passages and

camshaft A camshaft is a shaft that contains a row of pointed cams, in order to convert rotational motion to reciprocating motion. Camshafts are used in piston engines (to operate the intake and exhaust valves), mechanically controlled ignition systems ...

supports. The pistons were also aluminium castings. The

crankshaft A crankshaft is a mechanical component used in a piston engine to convert the reciprocating motion into rotational motion. The crankshaft is a rotating shaft containing one or more crankpins, that are driven by the pistons via the connecting ...

was a 6-throw design with 8 plain bearings and a double row ball thrust bearing between the front two. The connecting rods had bronze bush little ends and white metal big ends. The

crankcase In a piston engine, the crankcase is the housing that surrounds the crankshaft. In most modern engines, the crankcase is integrated into the engine block. Two-stroke engines typically use a crankcase-compression design, resulting in the fuel/a ...

was cast in two parts, the upper one with the housings for the crankshaft bearings.

Variants

;Asso XI R:(R - ''Riduttore'' - reduction gear) ;Asso XI R.C.:(C - ''Compressore'' - supercharged) ;Asso XI R.C.15 :Supercharger speed 75/7 times crankshaft; rated power at . ;Asso XI R.2C.15:(2C - second supercharger gearing) Supercharger speed 7 times crankshaft; rated power at . ;Asso XI R.2C.16:(2C - second supercharger gearing) Supercharger speed 7 times crankshaft; rated power at . ;Asso XI R.C.40:Supercharger speed 75/7 times crankshaft; rated power at . ;L.121 R.C.40:A version of the Asso XI, ;A.120 R.C.40: Inverted version of the L.121

Applications

* CANT Z.501 *

CANT Z.505 The CANT Z.505 was a prototype trimotor transport floatplane built by CANT in the 1930s. Development In 1934 the airline Ala Littoria issued a specification for the supply of a new scheduled seaplane to be used on its commercial routes by sea. T ...

CANT Z.508 The CANT Z.508 was a three-engine Italian flying boat developed from the CANT Z.501 for use as a heavy bomber. Design and development Designed as a scaled-up three-engine version of the single-engine Z.501 for use as a heavy bomber. The aircra ...

CANT Z.1007 The CANT Z.1007 ''Alcione'' (''Kingfisher'') was an Italian three-engined medium bomber, with wooden structure. Designed by Filippo Zappata, who also designed the CANT Z.506De Marchi and Tonizzo 1994, p. 27. it had "excellent flying characteri ...

* CANT Z.1011 * Caproni Ca.124 idro *

Caproni Ca.134 The Caproni Ca.134 was a biplane reconnaissance aircraft built by the Italian company Caproni in the 1930s. Design The Ca.134 was a conventional-looking, single-biplane, two-seater fixed-cart aircraft. The fuselage, made of a metal structure c ...

Caproni Ca.135 The Caproni Ca.135 was an Italian medium bomber designed in Bergamo in Italy by Cesare Pallavicino. It flew for the first time in 1935, and entered service with the Peruvian Air Force in 1937, and with the ''Regia Aeronautica'' (Italian Royal Air ...

Caproni Ca.405 The Piaggio P.32 was an Italian medium bomber of the late 1930s, produced by Piaggio, and designed by Giovanni Pegna. It was a modern design for its time, but was a failure due to lack of powerplants commensurate with its high wing loading. Desi ...

Caproni Campini N.1 The Caproni Campini N.1, also known as the C.C.2, is an experimental jet aircraft built in the 1930s by Italian aircraft manufacturer Caproni. The N.1 first flew in 1940 and was briefly regarded as the first successful jet-powered aircraft in hi ...

IMAM Ro.45 The Meridionali Ro.37 ''Lince'' ( Italian: "Lynx") was a two-seater Italian reconnaissance biplane, a product of the ''Industrie Meccaniche Aeronautiche Meridionali'' (IMAM) company. It appeared in 1934 and had a composite structure of wood a ...

Piaggio P.32 The Piaggio P.32 was an Italian medium bomber of the late 1930s, produced by Piaggio, and designed by Giovanni Pegna. It was a modern design for its time, but was a failure due to lack of powerplants commensurate with its high wing loading. Desig ...

Piaggio P.50 The Piaggio P.50 was an Italian prototype heavy bomber designed and built by Piaggio Aero, Piaggio for the ''Regia Aeronautica'' (Italian Royal Air Force). Design and development The P.50 was the first design by Giovanni Casiraghi—following an ...

* SAI Ambrosini S.S.4 *

Savoia-Marchetti SM.79 The Savoia-Marchetti SM.79 ''Sparviero'' (Italian for sparrowhawk) was a three-engined Italian medium bomber developed and manufactured by aviation company Savoia-Marchetti. It may be the best-known Italian aeroplane of the Second World War. Th ...

Design and development

Variants

Applications

Specifications (R.C.40)

See also

Note

References