The Hispano-Suiza 12N was one of two new V-12 engine designs first run in 1928 and was manufactured by

Hispano-Suiza Hispano-Suiza () is a Spanish automotive–engineering company. It was founded in 1904 by Marc Birkigt and Damian Mateu as an automobile manufacturer and eventually had several factories in Spain and France that produced luxury cars, aircraft en ...

's French

subsidiary A subsidiary, subsidiary company or daughter company is a company owned or controlled by another company, which is called the parent company or holding company. Two or more subsidiaries that either belong to the same parent company or having a s ...

for the Armee d'l'Air. It produced about , was the first to use gas nitride hardening and introduced wet cylinder liners into Hispano-Suiza's aircraft engine range. It powered the first non-stop flight from Europe to the United States.

Design and development

Up to 1927, Hispano-Suiza's many engine types, of various layouts and cylinder numbers, were all recognisable developments of the World War I V-8

Hispano-Suiza 8 The Hispano-Suiza 8 was a water-cooled V8 SOHC aero engine introduced by Hispano-Suiza in 1914, and was the most commonly used liquid-cooled engine in the aircraft of the Entente Powers during the First World War. The original Hispano-Suiza ...

. 1927-8 saw the introduction of four completely new engines, two V-12s and two with six cylinders inline. The Hispano-Suiza 12N, known by the manufacturers as the Type 61, was the larger of the V-12s, with a

displacement Displacement may refer to: Physical sciences Mathematics and Physics *Displacement (geometry), is the difference between the final and initial position of a point trajectory (for instance, the center of mass of a moving object). The actual path ...

of , the other being the 12M. Apart from capacity and power, these two engines had much in common. The 12M first ran in 1927 and the 12N a year later. Both 12M and 12N were 60° V engines with

carburettor A carburetor (also spelled carburettor) is a device used by an internal combustion engine to control and mix air and fuel entering the engine. The primary method of adding fuel to the intake air is through the venturi tube in the main meterin ...

inlets An inlet is a (usually long and narrow) indentation of a shoreline, such as a small arm, bay, sound, fjord, lagoon or marsh, that leads to an enclosed larger body of water such as a lake, estuary, gulf or marginal sea. Overview In marine geogra ...

and exhausts on the outer faces. There were three carburettors per bank, each charging a pair of

cylinders A cylinder (from ) has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base. A cylinder may also be defined as an infini ...

. Much of the new technology was in the cylinder design: these types introduced

wet liner In an internal combustion engine, the engine block is the structure which contains the cylinders and other components. In an early automotive engine, the engine block consisted of just the cylinder block, to which a separate crankcase was atta ...

s, an Hispano automobile engine innovation which brought the cooling water into direct contact with the steel cylinder barrel rather than by screwing it into an aluminium water jacket. This improved cooling, simplified assembly and allowed larger cylinder bores without increasing their separation. The cylinder barrels were open at top and bottom and threaded for screwing into the block only near the top, with valve seats ground into the aluminium cylinder head. The lower end of the barrel extended into the crankcase, simplifying both manufacture and assembly. Block and crankcase were bolted together. The 12M and 12N engines were the first to use the gas nitriding surface hardening process on the cylinder walls, which reduced both wear and oil consumption. They also used a novel, complicated but effective method of main bearing cooling, enhancing the local lubricant flow without requiring high overall oil pump speeds. Both types were designed so that Epicyclic gearing could be added or removed quickly; some earlier Hispano-Suiza engines offered gearing but as a permanent fixture on a specific sub-type. The gears added to the weight. In 1935 the 12Ner variant was fitted with an in-flight- electrically operated variable pitch propeller. The 12N series was developed into the 12Y (Type 73)

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 ...

engine, first run in 1932.

Operational history

A Hispano-Suiza 12Nb powered the Breguet XIX ''Point d'Interrogation'' on the first non-stop flight from Paris to New York in September 1930. This was the first east to west flight between Europe and the United States, rather than to the North American continent. In the early 1930s, 12N engines powered the

flying boat A flying boat is a type of fixed-winged seaplane with a hull, allowing it to land on water. It differs from a floatplane in that a flying boat's fuselage is purpose-designed for floatation and contains a hull, while floatplanes rely on fusela ...

s operating the French Atlantic and African routes. The

Swiss Swiss may refer to: * the adjectival form of Switzerland * Swiss people Places * Swiss, Missouri * Swiss, North Carolina *Swiss, West Virginia * Swiss, Wisconsin Other uses *Swiss-system tournament, in various games and sports *Swiss Internation ...

government, in the form of the KTA (Kriegstechninischen Abteilung or War Technical Department) purchased construction licences for the 12Nb and in 1932 eighty units were built at the

Saurer Adolph Saurer AG was a Swiss manufacturer of embroidery and textile machines, trucks and buses under the Saurer and Berna (beginning in 1929) brand names. Based in Arbon, Switzerland, the firm was active between 1903 and 1982. Their vehicles were ...

lorry factory.

Variants

''Data from Hispano Suiza in Aeronautics.'' ;12Nb/650: Compression ratio 6.2, maximum power at 2,100 rpm. ;12Nbr/650: Compression ratio 6.2, maximum power at 2,100 rpm. Gearing ratio of 2:1 or 1.61:1. ;12Ns: Compression ratio 7, nominal power at 2,200 rpm. For Schneider Cup 1928. ;12Nsr: Compression ratio 10, nominal power at 2,400 rpm. For Schneider Cup 1931. Farman compressor. ;12Nc: Compression ratio 6.2, nominal power at 2,000 rpm. For Ford 14A Trimotor. ;12Ncr: ;12Ndr: Electrically controlled pitch propeller, anti-clockwise turning (1935). ;12Ner: As 12Ndr, modified with articulated

connecting rod A connecting rod, also called a 'con rod', is the part of a piston engine which connects the piston to the crankshaft. Together with the crank, the connecting rod converts the reciprocating motion of the piston into the rotation of the cranksh ...

s. ;12Nfr: As Ndr, clockwise turning. ;12Ngr: As Ner, clockwise turning.

Applications

Specifications (12Nbr/650)

References