Hispano-Suiza 12M

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. 1927-8 saw the introduction of four completely new engines, two V-12s designed by Marc Birkigt, and two with six cylinders inline. The Hispano-Suiza 12M, known by the manufacturers as the Type 57, was the smaller of the V-12s, with a displacement of 27.0 L (1,648 cu in), the other being the 36.0 L (2,197 cu in) 12N. 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 carburettors, inlets and exhausts on the outer faces. There were three carburettors per bank, each charging a pair of cylinders. Much of the new technology was in the cylinder design: these types introduced wet liners, 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. In 1931 the unit cost was 240,000 FF.

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 Farman gears added 45 kg (99 lb) to the weight.

The first commercial version of the 12M was the 12Mb of 1929. This had a compression ratio of 6.2 and a maximum power output of 432 kW (580 hp) at a speed of 2,100 rpm. In geared-down form it became the 12Mbr. These both had aluminium crankcases but the next model, the 12Mc of 1930, replaced the aluminium with Elektron metal both there and in other previously aluminium components. Though rather brittle, Elektron metal has only 2/3 the density of aluminium and the result was a 20 kg (44 lb) weight reduction from the 12Mb to the 12Mc. The 12Mc also had an increased compression ratio of 7.0, raising the power from the nominal 478 kW (575 hp) of the 12Mb to 477 kW (640 hp). The model 12Md retained the Elektron metal components but returned to the 6.2 compression ratio of the 12Mb. Both 12Mc and 12Md had geared down versions, the 12Mcr and 12Mdr respectively.

The 12Mc was an early example of an attempt to solve the problem of falling engine power with increasing altitude; it was “undercharged”, running lean at sea level and only developing its maximum power at 2,000 m (6,490 ft). A final 12M variant, the 12Mdsh run in 1932, addressed this problem differently; it was the first Hispano-Suiza engine to be supercharged, blown by a Rateau turbine. It produced 477 kW (640 hp) at 2,250 rpm at an altitude 2,950 m (9,678 ft). Test flown in a Dewoitine D.32, it maintained power up to 5,500 m (18,000 ft). The 12M series was developed into the 12X (Type 72) supercharged engine, first run in 1931.

The Swiss government, in the form of the KTA (Kriegstechninischen Abteilung or War Technical Department) purchased construction licences for the 12Mb and in 1932 sixty units were built at the Schweitzerische Lokomotive und Maschinfabrik factory.

A Blériot-SPAD S.91-7, powered by a 12Mc engine, set a 500km closed-circuit record of 308.78 km/h (191.91 mph) on 2 June 1932.

Variants:

12Mb/500
Compression ratio 6.2. Nominal power 428 kW (575 hp) at 2,000 rpm.

12Mbr/500
Compression ratio 6.2. Nominal power 421 kW (565 hp) at 2,000 rpm. As 12Mb but with Farman reducer.

12Mc/500
Compression ratio 7.0. Nominal power 477 kW (640 hp) at 2,200 rpm. Elektron crankcase and other components.

12Mcr/500
As 12Mc but with Farman reducer.

12Md
Compression ratio 6.2. Nominal power 428 kW (575 hp) at 2,100 rpm. Elektron crankcase and other components.

12Mdr
As 12Md but with Farman reducer.

12Mdsh
Nominal power 477 kW (640 hp) at 2,250 rpm and altitude 2,950 m (9,678 ft). First supercharged version.

Applications:
Blériot-SPAD 91-7[4]
Dewoitine D.32[2]
Lioré et Olivier LeO 252, 235, 234, 236
Nieuport-Delage 622 and 629

Specifications:

12Mbr/500
Type: V-12, water cooled
Bore: 150 mm (5.90 in)
Stroke: 170 mm (6.69 in)
Displacement: 27.0 L (1,648 cu in)
Dry weight: 455 kg (1,003 lb)
Reduction gear: 2:1
Power output: (normal) 421 kW (565 hp) at 2,000 rpm
Compression ratio: 6.2

Hispano-Suiza 12Y / HS-77 / Klimov M-100 / Avia Vr. 36 / Avia HS 12Ydrs

Hispano-Suiza 12Y

The 12Y was a fairly traditional in construction, a 36-litre water-cooled V-12 with the two cast aluminium cylinder banks set at 60 degrees to each other. The 12Y design was based on the earlier and smaller, 12X. The cylinder heads were not removable, instead the entire block could be quickly removed from the engine. This made it somewhat famous for being leak-proof, a design feature that was considered by other designers and almost became a part of the Rolls-Royce Merlin. The major design change from the earlier 12X was to use a master-articulated connecting rod system, instead of the fork-and-blade type. A single overhead camshaft (SOHC) drove the valves, which were filled with liquid sodium for cooling. Only a single intake and exhaust valve were used, unlike most designs of the era which had moved to three or four valves per cylinder. A single-stage, single-speed supercharger was standard, although the art of designing a useful intake was not as well developed as in other countries, and high altitude performance was always lacking.
The first 12Y test articles were constructed in 1932, and almost immediately the entire French aviation industry started designing around it. At the time the engine developed only 760 hp (570 kW), but it was clear it had potential to the 1,000 hp (750 kW) class. An early modification led to the Hispano-Suiza 12Ycrs which used a hollow propeller shaft to allow a 20 mm cannon to fire through the propeller spinner (a combination known as a moteur-canon). All later designs shared this feature. The 12Ydrs was the next major series, with a basic rating of 836 hp (623 kW) at sea level with a compression ratio of 5.8:1.
The Armée de l’Air changed their nomenclature, so the next version was the Hispano-Suiza 12Y-21, which increased the compression ratio to 7:1, when running on 100 octane gasoline. This boosted power to 867 hp (647 kW). In 1936 the connecting rod design was changed slightly to create the 12Y-31, but the lower 5.8:1 compression ratio was retained and the power was increased only slightly over the drs model to 850 hp (630 kW). Nevertheless this became one of the most used engine designs of the pre-war era, used in almost all French fighter designs and prototypes.
A real effort to improve the performance of the engine in 1938 resulted in the Hispano-Suiza 12Y-45, which used the S-39-H3 supercharger co-designed by André Planiol and Polish engineer Joseph Szydlowski. The Szydlowski-Planiol device was larger, but much more efficient than the indifferent Hispano-Suiza models. When used with 100 octane fuel, the supercharger boosted to the -21’s 7:1, increasing power to 900 hp (670 kW). Combined with the fully adjustable Ratier propeller, this allowed the D.520 to perform as well as contemporary designs from Germany and England.
Another improvement in supercharging led to the Hispano-Suiza 12Y-49, whose performance improved from 850 hp (630 kW) at sea level to 920 hp (690 kW) at just over 10,000 ft (3,000 m). This improvement in power with altitude was a common feature of most engines of the era, the result of the supercharger “robbing” power at low altitudes.
The final major version was the 1,085 hp (809 kW) Hispano-Suiza 12Y-51, which had just started into production at the time of the Armistice with Germany. The -51 was the first version that came close to the performance limits of the engine, although the single-stage supercharging meant that it was unable to compete with designs from England and Germany above 15,000 ft (5,000 m).
Foreign derivatives
In the early 1930s the Czechoslovakian Republic gained rights to build a license version of the HS-12Y. This was initially known locally as the Avia Vr. 36 and was produced by Avia (Škoda) at Prag – Čakovice. The engine was intended to become the standard powerplant of all Czech military aircraft. Both the HS-12Ycrs and HS-12Ydrs were built in quantity and were more commonly known by these names rather than any Czech designation. Aircraft powered by these engines included the Avia B-34, Avia B-534, Avia B-71, Avia B-35 and Avia B-135.
In the mid-1930s, Russian engineer Vladimir Klimov was sent to France to obtain a license for local production of the 12Y. A series of design changes were added to cope with cold weather operation, and the engine entered production in 1935 as the Klimov M-100 with about 750 hp (560 kW). However a series of continual upgrades increased the allowable RPM from the 12Y’s fairly low 2,400 to 2,700, thereby increasing power to 1,100 hp (820 kW). The resulting design, the Klimov M-105 (VK-105) became one of the major Soviet engine designs during the war, powering all Yakovlev fighters.

Variants:

Type 73 Hispano 12Yb
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1932
Compression: 6.4
Power: 785 hp
Max power rpm: 2,200
TO power: 785 hp
Output reduction: 1.5
Weight: 415 kg)
Rated power (650 hp) less than nominal 785 hp
Left turning

Type 73 Hispano 12Ygrs
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1932
Compression: 5.8
Power: 850 hp
Max power rpm: 2,400
TO power: 800 hp
Output reduction: 1.5
Supercharger optimum altitude: 4,000 m
Weight: 430
Rated power (650 hp) less than nominal 850 hp
Left turning

Type 73 Hispano 12Y dr
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Compression: 6.4
Year: 1934
Power: 800 hp
Max power rpm: 2,200
TO power: 800 hp
Output reduction: 1.5
Weight: 440
Left turning

Type 73 Hispano 12Y drs
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1934
Compression: 5.8
Power: 860 hp
Max power rpm: 2,400
TO power: 835 hp
Output reduction: 1.5
Supercharger optimum altitude: 4,000 m
Weight: 470 kg
Left turning

Type 73 Hispano 12Y 12Ydrs1
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1934
Compression: 5.8
Power: 880 hp
Max power rpm: 2,400
TO power: 890 hp
Output reduction: 1.5
Supercharger optimum altitude: 2,400 m
Weight: 470 kg
Left turning

Type 73 Hispano 12Y drs2
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1934
Compression: 5.8
Power: 930 hp
Max power rpm: 2,400
TO power: 992 hp
Output reduction: 1.5
Supercharger optimum altitude: 900 m
Weight: 470 kg
Left turning

Type 73 Hispano 12Y frs
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1934
Compression: 5.8
Power: 860
Max power rpm: 2,400 rpm
TO power: 835 hp
Output reduction: 1.5
Supercharger optimum altitude: 4,000 m
Weight: 470 kg
Right turning

Type 73 Hispano 12Y frs1
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1934
Compression: 5.8
Power: 880 hp
Max power rpm: 2,400
TO power: 890 hp
Output reduction: 1.5
Supercharger optimum altitude: 2,400 m
Weight: 470 kg
Right turning

Type 73 Hispano 12Y frs2
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1934
Compression: 5.8
Power: 930 hp
Max power rpm: 2,400
TO power: 992 hp
Output reduction: 1.5
Supercharger optimum altitude: 900m
Weight: 470 kg
Right turning

Type 73 Hispano 12Y 21
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1935
Compression: 7.0
Power: 910 hp
Max power rpm: 2,400
TO power: 880 hp
Output reduction: 1.5
Supercharger optimum altitude: 3,600m
Weight: 470 kg

Type 73 Hispano 12Y 25
Configuration: 60° V-12
Bore: 150 mm (5.906 in)
Stroke: 170 mm (6.693 in)
Capacity: 36.0 litres (2,199.9 cu,in)
Length: 1,722 mm (67.8 in)
Width: 764 mm (30.08 in)
Height: 935 mm (36.81 in)
Year: 1935
Compression: 5.8
Power: 860 hp
Max power rpm: 2,400
TO power: 943 hp
Specific power: 17.08 kW/lt (0.38 hp/cu.in)
Specific fuel consumption: 328 g/(kW/hr) (0.54 lb/(hp/hr))
Oil consumption: 11 g/(kW/hr) (0.28 oz/(hp/hr))
Power-to-weight ratio: 1.32 kW/kg (0.8 hp/lb)
Output reduction: Spur, 1.5
Fuel system: Six Solex 56 S.V.C carburetors
Fuel type: 85/100 octane gasoline
Supercharger: Gear-driven single-speed centrifugal type, 10.0:1 gear ratio
Supercharger optimum altitude: 3,600m
Dry weight: 475 kg (1,050 lb)
Cooling system: Pressurised, Liquid-cooled: 600 litres/min.
Valvetrain: One intake and one sodium-filled exhaust valve per cylinder actuated via a single overhead camshaft per bank.
Left turning, variable ignition timing

Type 73 Hispano 12Y 27
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1935
Compression: 5.8
Power: 900 hp
Max power rpm: 2,400
TO power: 950 hp
Output reduction: 1.8
Supercharger optimum altitude: 850m
Weight: 483 kg

Type 73 Hispano 12Y 33
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1936
Compression: 7.0
Power: 965 hp
Max power rpm: 2,400
TO power: 960 hp
Output reduction: 1.5
Supercharger optimum altitude: 2,250 m
Weight: 490 kg

Type 73 Hispano 12Y 39
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1936
Compression: 7.0
TO / Max Power: 1000 hp
Max power rpm: 2,400
Output reduction: 1.5
Supercharger optimum altitude: 3,400m

Type 73 Hispano 12Y 5
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1938
Power: 920 hp
Max power rpm: 2,400
TO power: 950 hp
Output reduction: 1.5
Supercharger optimum altitude: 10,000m
3 speed compressor

Type 77 Hispano 12Y crs
Configuration: 60° V-12
Bore: 150 mm (5.906 in)
Stroke: 170 mm (6.693 in)
Capacity: 36.0 litres (2,199.9 cu,in)
Length: 1,722 mm (67.8 in)
Width: 764 mm (30.08 in)
Height: 935 mm (36.81 in)
Year: 1934
Compression: 5.8
Power: 860 hp
Max power rpm: 2,400
TO power: 835 hp
Specific power: 17.08 kW/lt (0.38 hp/cu.in)
Specific fuel consumption: 328 g/(kW/hr) (0.54 lb/(hp/hr))
Oil consumption: 11 g/(kW/hr) (0.28 oz/(hp/hr))
Power-to-weight ratio: 1.32 kW/kg (0.8 hp/lb)
Output reduction: Spur, 1.5
Supercharger: Gear-driven single-speed centrifugal type, 10.0:1 gear ratio
Supercharger optimum altitude: 4,000m
Weight: 470 kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.
Fuel system: Six Solex 56 S.V.C carburetors
Cooling system: Pressurised, Liquid-cooled: 600 litres/min.
Valvetrain: One intake and one sodium-filled exhaust valve per cylinder actuated via a single overhead camshaft per bank.

Type 77 Hispano 12Y brs
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1934
Compression: 5.8
Power: 860hp
Max power rpm: 2,400
TO power: 835hp
Output reduction: 1.0625
Supercharger optimum altitude: 4,000m
Weight: 470kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.

Type 77 Hispano 12Y 29
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Compression: 7.2
Power: 920hp
Max power rpm: 2,400
TO power: 910hp
Output reduction: 1.5
Supercharger optimum altitude: 3,600m
Weight: 475kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.

Type 77 Hispano 12Y 31
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1936
Compression: 5.8
Power: 860hp
Max power rpm: 2,400
TO power: 830hp
Output reduction: 1.5
Supercharger optimum altitude: 3,250m
Weight: 468kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.
Redesigned connecting rods

Type 77 Hispano 12Y 37
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1936
Compression: 7.0
Power: 960hp
Max power rpm: 2,400
TO power: 1,050hp
Output reduction: 1.8
Supercharger optimum altitude: 1,250m
Weight: 483kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.

Type 77 Hispano 12Y 41
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1936
Compression: 7.0
Power: 920 hp
Max power rpm: 2,400
Output reduction: 1.5
Supercharger optimum altitude: 3,600m
Weight: 483kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.

Type 77 Hispano 12Y 45
Configuration: 60° V-12
Bore: 150 mm (5.906 in)
Stroke: 170 mm (6.693 in)
Capacity: 36.0 litres (2,199.9 cu,in)
Length: 1,722 mm (67.8 in)
Width: 764 mm (30.08 in)
Height: 935 mm (36.81 in)
Compression: 7.0
Power: 920hp
Max power rpm: 2,400
TO power: 935hp
Output reduction: Spur, 1.5
Fuel system: Six Solex 56 S.V.C carburetors
Fuel type: 92/100 octane gasoline
Specific power: 17.08 kW/lt (0.38 hp/cu.in)
Specific fuel consumption: 328 g/(kW/hr) (0.54 lb/(hp/hr))
Oil consumption: 11 g/(kW/hr) (0.28 oz/(hp/hr))
Power-to-weight ratio: 1.32 kW/kg (0.8 hp/lb)
Supercharger: Gear-driven single-speed centrifugal type, 10.0:1 gear ratio
Supercharger optimum altitude: 4,200m
Dry weight: 515 kg (1,140 lb)
Cooling system: Pressurised, Liquid-cooled: 600 litres/min.
Valvetrain: One intake and one sodium-filled exhaust valve per cylinder actuated via a single overhead camshaft per bank.
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.
Szydlowsky-Planiol (SP) supercharger

Type 77 Hispano 12Y 47
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1936
Compression: 5.8
Power: 860 hp
Max power rpm: 2,400
TO power: 830 hp
Output reduction: 1.5
Supercharger optimum altitude: 3,250m
Weight: 468 kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.

Type 77 Hispano 12Y 49
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Compression: 7.0
Power: 910hp
Max power rpm: 2,400
TO power: 910hp
Output reduction: 1.5
Supercharger optimum altitude: 5,250m
Weight: kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.
Szydlowsky-Planiol (SP) supercharger, variable ignition timing

Type 77 Hispano 12Y 51
Configuration: V-12
Bore: 150 mm
Stroke: 170 mm
Capacity: 36.0 litres
Year: 1939
Compression: 7.0
Power: 1,000hp
Max power rpm: 2,500
TO power: 1,100hp
Output reduction: 1.5
Supercharger optimum altitude: 3,260m
Weight: 492kg
20 mm calibre Hispano-Suiza 404 cannon between cylinder banks, firing through propeller shaft.
Szydlowsky-Planiol (SP) supercharger, variable ignition timing

Licence built variants:

Avia Vr. 36
License production in Czechoslovakia.

Klimov M-100
License production in the USSR.

Hispano-Suiza HS-77
Licence-built 12Ycrs produced in Switzerland.

Applications:
Amiot 370
Arsenal VB 10
Arsenal VG-33
Avia 156
Avia B-534
Bloch MB.177
Dewoitine D.510
Dewoitine D.513
Dewoitine D.520
EKW C-35
Fairey Fantôme
Farman NC.223.3
Farman NC.223.4
Ikarus IK-2
Latécoère 298
Latécoère 521
Loire-Nieuport 161
Morane-Saulnier M.S.406
Morane-Saulnier M.S.475
ANF Les Mureaux 110-119 series
Renard R-36
Rogozarski IK-3
Wibault 366

12Y Derivatives Applications:
Arkhangelsky Ar-2
Lavochkin-Gorbunov-Goudkov LaGG-1
Lavochkin-Gorbunov-Goudkov LaGG-3
Mörkö-Morane
Petlyakov Pe-2
Petlyakov Pe-3
Yakovlev Yak-1
Yakovlev Yak-2
Yakovlev Yak-3
Yakovlev Yak-4
Yakovlev Yak-7
Yakovlev Yak-9
Yermolayev Yer-2

Hispano-Suiza 8A / Wolseley W.4B Adder / Wolseley W.4A Python / Wright-Hisso A / Wright-Hisso H / Mitsubishi “Hi” shiki / Wright-Hisso V-720

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 engine in the aircraft of the Entente Powers during the First World War. The original Hispano-Suiza 8A was rated at 140 hp (102 kW) and the later Hispano-Suiza 8F reached 300 hp (220 kW).

HS-8 engines and variants produced by Hispano-Suiza and other companies under licence were built in twenty-one factories in Spain, France, Britain, Italy, and the U.S. Derivatives of the engine were also used abroad to power numerous aircraft types and the engine can be considered as the ancestor of another successful engine by the same designer, the Hispano-Suiza HS-12Y (and Soviet Klimov V12 derivative aero-engines) which served in World War II.

When World War I began, the production lines of the Barcelona based Hispano-Suiza automobile and engine company were switched to the production of war materiel. Chief engineer Marc Birkigt led work on an aircraft engine based on his successful V8 automobile engine. The resulting engine, called the Hispano-Suiza 8A (or HS-8A), made its first appearance in February 1915.

The first 8A kept the standard configuration of Birkigt’s existing design: eight cylinders in 90° Vee configuration, a displacement of 11.76 litres (717.8 cu in) and a power output of 140 hp at 1,900 rpm. In spite of the similarities with the original design, the engine had been substantially refined. The crankcase was machined from a solid piece of steel. The cylinders were cast aluminium with steel liners. The SOHC cylinder heads were also made of aluminium, using a rotary driveshaft (tower gear) coming up from the crankcase along the rear end of each cylinder bank, with the final drive for each cylinder bank’s camshaft accommodated within a semicircular bulge at the rear end of each valve cover. Aluminium parts were coated in vitreous enamel to reduce leakage. All parts subject to wear, and those critical for engine ignition were duplicated: spark plugs for dual ignition reliability, valve springs, magnetos, etc.

Although engine reliability was a great concern in these opening stages of aviation, the HS-8A also provided a good power-to-weight ratio and development potential. The engine and its accessories weighed 185 kg (408 lb), making it 40% heavier than a rotary engine of equivalent power. The design also promised far more development potential than rotary engines which, in spite of being the most common type then in use for aircraft, were getting close to the limits of their potential. Rotary engines of increased power generally had increased weight, which in turn increased the already serious gyroscopic torque generated by the engine’s rotation. A further increase in torque was considered unacceptable, and the power-to-weight ratio of the new rotary engines under development did not appeal to aircraft designers.

The new engine was presented to the French Ministère de la Guerre (Ministry of War) in February 1915, and tested for 15 hours at full power. This was standard procedure for a new engine design to be admitted in military service. However, because of lobbying by French engine manufacturers, the HS-8A was ordered to undergo a bench test that no French-made engine had yet achieved successfully: a 50-hour run at full speed. The HS-8A was therefore sent back to Chalais-Meudon on July 21, 1915 and tested for 50 hours, succeeding against all expectations.

French officials ordered production of the HS-8A to be started as soon as possible and issued a requirement for a new single-seat high-performance fighter aircraft using the new engine. The SPAD VII was the result of this requirement and would allow the Allies to regain air superiority over the Germans.

Guynemer informed Bechereau in December 1916 that “the Halberstadt [while] not faster, climbs better, consequently it has the overall advantage”. In the quest for more power, Marc Birkigt increased the compression ratio of the 8A engine from 4.7 to 5.3, which in turn raised its revolutions from 1500 to 1800 per minute. This resulted in a power output of 180hp, enabling a significant improvement in the SPAD VII’s performance to be achieved. Apart from the extra power, the new Hispano-Suiza 8Ab proved extremely reliable.

Hispano Suiza 8Ca

Approximately 49,800 were built.

The Wolseley Viper is a British-built, high-compression derivative of the Hispano Suiza HS-8 liquid-cooled V-8 engine, built under licence by Wolseley Motors during World War I and first run in 1918.

It powered later models of the S.E.5a, SPAD VII and other British or British-built aircraft designed for the Hispano-Suiza.

Wolsley Viper

Variants:

8A (HS-8A)
The first model of the Hispano-Suiza 8 produced in any quantity.

8Aa (HS-8Aa)
The HS-8Aa, which entered production in July 1915, was the production variant of the basic HS-8A type, with increased power output: 150 hp (110 kW) at 2,000 rpm. Early HS-8A engines were plagued with various problems which required further work. The 150 hp HS-8Aa was the standard powerplant for early-production SPAD VIIs. The demand for the Hispano-Suiza engine was such that other manufacturers began producing it under licence, in France, Great Britain (Wolseley Adder), Italy (Nagliati in Florence and Itala/SCAT in Turin) and Russia. Total production of the HS-8Aa amounted to some 6,000 engines. To avoid the problems experienced by the 8A, Wolseley reduced the compression ratio to 4.7 in the Adder but opted for 5.3 in other variations such as the Viper.

8Ab (HS-8Ab)
The HS-8Ab was yet another evolution of the HS-8A. By increasing the compression ratio from 4.7 to 5.3, Birkigt was able to increase the power output to 180 hp (132 kW) at 2,100 rpm. The HS-8Ab began replacing the 8Aa on SPAD VIIs in early 1917.

8Ac (HS-8Ac)

8B (HS-8B)
The HS-8Ab had been plagued by engine failures due to the high compression ratio: piston heads were sometimes pierced and engines seized. In another ploy to increase the power output of the engine, Birkigt chose to increase engine speed.

8Ba (HS-8Ba)
The first, the HS-8Ba, kept the 4.7 compression ratio of the HS-8Aa but delivered 200 hp (147 kW) at 2,300 rpm.

8Ba (HS-8Bb)
The second version, the HS-8Bb, had a compression ratio of 5.3. A reduction gear (3:4 ratio) was fitted to compensate for the increased engine speed. However the reduction gear system was fragile, and often broke down, sometimes with spectacular results ending up with the entire propeller, driveshaft and driven gear parting company from the airframe. Progressive refinement of the engine brought the available power to 235 hp by the end of 1917.
The HS-8B was used to power the earliest versions of the S.E.5a, all examples of the SPAD S.XII and SPAD S.XIII, front-line versions of the Sopwith Dolphin and several other Allied aircraft types, with its gear reduction easily identifiable in vintage World War I photos, from its use of a clockwise (viewed from in front, otherwise known as a left hand tractor) rotation propeller.

8Ba (HS-8Be)

Hispano-Suiza 8Be

8Ca (HS-8Ca)
The HS-8Ca, a gear-reduction equipped powerplant with a resultant clockwise rotation propeller like the 8B, produced 220 hp at 2,100 rpm. It had a manually loaded 37 mm Puteaux SA 18 cannon mounted between the cylinder banks (a so-called moteur-canon) that could fire a single shot at a time through the hollow drive shaft without propeller interference. The engine was used on the SPAD S.XII.

Hispano Suiza 8Ca

8F (HS-8F)
The HS-8F was basically an enlarged version of the HS-8B, and was intended for use in bombers. Displacement rose to 18.5 liters (1,127.3 in3), with a power of 300 hp (220 kW) at 2,100 rpm (eq. 750 lb·ft torque). Despite the increased weight of 256 kg (564 lb), the HS-8F was installed in fighters such as the Nieuport-Delage NiD 29 and Martinsyde Buzzard, and it would have powered the never-produced Mk.II version of the Sopwith Dolphin. Engine speed being lower than that of the HS-8B, the reduction gear was deleted, thereby increasing engine reliability.

8Fa (HS-8Fa)

8Fb (HS-8Fb)

8Fd (HS-8Fd)

Wolseley W.4B Adder I

Wolseley W.4B Adder II

Wolseley W.4B Adder III

Wolseley W.4A Python I

Wolseley W.4A Python II

Wolseley W.4A Viper
Was an improved 8A. Wolseley’s engineers removed problems with the crankshaft and increased the compression ratio to give more power. It did not need the reduction gearing of the H-S8.

Wolseley W.4A Viper II
The Viper II could deliver 210 hp at 2,000 rpm.

Wright-Hisso A

Wright-Hisso E
The American Wright-Martin aviation firm licence-produced the original 150 hp HS-8Aa engine as the Wright-Hispano E, for use in World War I combat aircraft to be built in the United States – it found its way into the JN-4H version of the Curtiss Jenny, replacing the Curtiss OX-5 liquid-cooled V8 engine of only 90 hp output.
Wright-Hisso H

Wright-Hisso I

Wright-Hisso T

Applications:
Austin-Ball A.F.B.1
Avia BH-21
Avia BH-22
Bartel BM-5
Bernard SIMB AB 10
Blanchard Brd.1
Caudron C.59
Caudron R.11
Curtiss JN-4H Jenny
FBA Type H
Fokker D.IX
Fokker D.X
Fokker D.XII
Fokker S.III
Gourdou-Leseurre GL.21
Hanriot HD.5
Hanriot HD.15
Hanriot HD.20
Letov Š-7
Letov Š-13
Letov Š-14
Martinsyde F.4 Buzzard
Nieuport 29 (8Fb)
S.E.5 and S.E.5a (8a and Viper),
Sopwith Dolphin (8B)
Sopwith Cuckoo
SPAD S.VII (8a)
SPAD S.XI (8Be)
SPAD S.XII (8Cb), with 37 mm calibre moteur-canon mount through the hollow propshaft
SPAD S.XIII (8Be)
Standard J-1 training biplanes, especially on restored, airworthy examples
Waco DSO (8a)
Wibault 1

Wright-Hispano E
Boeing NB-2
AT-3
Consolidated PT-1
Cox-Klemin TW-2
Dayton-Wright TW-3
Huff-Daland TW-5
Curtiss AT-4
Vought VE-7
Waco DSO

Mitsubishi “Hi” shiki
200 HP (8B)
Yokosuka Ro-go Ko-gata
Hansa-Brandenburg W.29 (Japanese version)

300 HP (8F)
Mitsubishi 1MF
Mitsubishi 2MR

Wolsely W.4 Applications:
Airco DH.9
Avro 552
Bristol M.R.1
Bristol Tourer
Cierva C.8
Martinsyde F.6
Royal Aircraft Factory S.E.5a
Sopwith Antelope
Sopwith Cuckoo

Specifications:

Hispano-Suiza 8a
Type: 8-cylinder liquid-cooled Vee piston engine
Bore: 120 mm (4.724 in)
Stroke: 130 mm (5.118 in)
Displacement: 11.76 L (717.8 in3)
Dry weight: 445 lb (202 kg)
Fuel system: 1 Claudel or Zenith Carburetor
Cooling system: liquid
Fuel consumption: 0.51 lb/(hp·h)
Oil consumption: 0.03 lb/(hp·h)
Power output: 140 hp at 1900 rpm
Length: 1.19 m
Width: 0.81 m
Height: 0.77 m
Compression ratio: 4.7

8Aa
Bore: 120 mm
Stroke: 130 mm
Displacement: 11.76 lt
Compression ratio: 4.7
Length: 1.25 m
Width: 0.83 m
Height: 0.81 m
Weight: 215 kg
Power output: 150 hp at 2000 rpm

8Ab
Bore: 120 mm
Stroke: 130 mm
Displacement: 11.76 lt
Compression ratio: 5.3
Length: 1.31 m
Width: 0.85 m
Height: 0.87 m
Weight: 230 kg
Power output: 180 hp at 2100 rpm

8B
Bore: 120 mm
Stroke: 130 mm
Displacement: 11.76 lt
Compression ratio: 5.3
Length: 1.36 m
Width: 0.86 m
Height: 0.90 m
Weight: 236 kg
Power output: 200/235 hp at 2300 rpm

8F
Bore: 140 mm
Stroke: 150 mm
Displacement: 18.47 lt
Compression ratio: 5.3
Length: 1.32 m
Width: 0.89 m
Height: 0.88 m
Weight: 256 kg
Power output: 300 hp at 2100 rpm

W.4A Viper
Type: 8-cylinder, upright, 90 degree Vee engine
Bore: 4.72 in (120 mm)
Stroke: 5.12 in (130 mm)
Displacement: 716.8 cu in (11.77 L)
Dry weight: 500 lb
Fuel system: Twin Zenith-Duplex carburettors
Cooling system: Liquid-cooled
Reduction gear: Direct drive, Right-hand tractor
Power output: 200 hp at 2,000 rpm (takeoff power)
Compression ratio: 5.3:1

Hispano HS-50

During World War I, the Spanish Air Arm was unable to obtain combat aircraft from abroad to modernise its operational units. Hispano enlisted the services of French designed Emile Dewoitine who designed a fighter monoplane, the HS-50, which was to be powered by the Hispano-Suiza HS-12-Z-89 engine.

The design reached full-scale mock-up stage when the decision was made to build the Messerschmitt Bf109G-2 under licence.

Hispano HA-300 / XC-6

HA-300P

The HA-300P research glider was to provide advance information on the probable flight characteristics of the powered aircraft.

Rolled out of Military Factory No. 36 at Helouan for the first time in 1963, the Messerschmitt designed supersonic interceptor was expected to commence flight trials with an Indian test pilot. Development on the Hispano HA 300, or, XC 6, began in Spain and was subsequently shelved. The fighter is powered by two 4,850 lb.s.t. (2 200 kgp) Bristol Siddeley Orpheus 703 turbojets for initial flight trials, but the definitive version is expected to be powered by a pair of 7,000 lb.s.t. (3 175 kgp) turbojets of a type developed in Egypt by Ferdinand Brandner. Whereas the fighter is only likely to attain about Mach 1.2 with Orpheus engines, a maximum speed of the order of Mach 2.2 is anticipated with the Brandner designed engine which, if successful, may also power the Hindustan HF 24. Basically of clipped delta planform, and featuring a long, needle nose, the fighter has side by side mounted engines, a narrow track, fuselage housed undercarriage, and a Martin Baker zero altitude ejection seat.

HA-300P
Wingspan: 20 ft 2 in
Length: 33 ft 5.5 in
Wing area: 215.278 sq.ft

Hispano HA.220 Super Saeta

HA 200 Saeta development potential as a lightweight ground attack aircraft lead, via the two seat HA 200E Super Saeta with more powerful Marbore engines, to the purpose built, single seat HA 220 Super Saeta, with increased armour, self¬-sealing fuel tanks and an additional fuel tank in the rear cockpit, replacing the second seat. Powered by two 1,058 lb thrust Marbore VI engines, the rear cockpit is used to accommodate an additional fuel tank. Armament can comprise a variety of bombs, guns, and rockets on under-¬fuselage/wing stations.
Two Browning M 3 machine guns.
Prototype (XC.10C) flown for first time on April 25, 1970. EdeA designation C.10C, later A.10C.
Twenty five were built.
Military Users: Egypt, Spain.

HA 220 Super Saeta / C-10C
Wing span: 35 ft 10 in (10.93 m)
Maximum speed: 435 mph (700 km/h).

Hispano HA-200 Saeta / Helwan HA 200B AI Kahira

A.10B

Hispano decided to build a basic jet trainer using two Marbore II engines, and designed the HA.200 Saeta (Arrow) Spain’s first jet aircraft which used many components from the HA.100 Trianaa, including the wings and rear fuselage.

Hispano HA-200 Saeta Article

Willy Messerschmitt supervised the design. The engines, mounted in the lower forward fuselage, were fed from an air intake in the nose, and exhausted from two nozzles below the trailing edge of the wing roots. The HA.200 stored its fuel in two wing and two fuselage tanks.

Two prototypes were built and first flew on 12 August 1955 with the Fernando Juan Valiente. 190 were built, both by Hispano and under a licence agreement in Egypt (as the Helwan HA 200B AI Kahira).

Prototype HA-200 Saeta EC-AMM

From the autumn of 1957 an experimental program was initiated by INTA. Ten pre-production aircraft were ordered by the Spanish Air Force, of which 5 will be transformed into HA-200 A (E14A Ejército del Aire in). The first aircraft was to fly on July 21, 1960, the rest be be delivered until 1962.

An additional series of 30 HA-200 A was built. The first of them flew October 11, 1962, the others being delivered between 1963 and 1965. In April 1965 flew the first HA-200 B (C10B in Ejército del Aire service) of which 55 were built and incorporated in the Ejército del Aire over 1965-1967.

The Hispano HA-200-R1 Saeta (two turbomeca Marbore IIA turbojet engine)

Hispano’s Saeta fulfilled jet training, ground attack training and, in the dedicated single seat HA.220 model, limited strike roles in Spainish service. The indigenous CASA 101 Aviojet provided the replacement, deliveries commencing in 1980.

The Egyptian aircraft were supplanted by the Aero L 29 Delfin.

Gallery

Variants:

HA 200R Saeta
Prototype EC AMM first flew on August 12, 1955, followed by second prototype. Spanish Air Force (Ejercito del Aire EdeA) designation XE.14 for the prototypes and E.14 for 10 pre-production examples, five of which were brought up to HA 200A status.

HA 200A Saeta
First production batch (of 25), powered by Turbomeca Mabore lls, first example flown on October 11, 1962. Much refined over earlier HA.200s. EdeA designation E.14A. Attack version (two hard points) C.10A, later A.10A.

HA 200B AI Kahira
Version for Egyptian Air Force. 20mm Hispano cannon in the nose, replacing 7.7min Breda Safat machine guns of the HA.200A. First of five Spanish built examples flown on July 21, 1960. 63 HA¬200Bs built under licence in Egypt as the AI Kahira (Cairo) at Factory 36, Helwan, Cairo.

HA 200D Saeta
Further refined production batch, EdeA designation E.14B. 55 built.

HA 200E Saeta
Dedicated ground attack/counter insurgency aircraft, with four wing hardpoints and Mabore VIs. Conversions (about 40) undertaken from HA 200Ds, designated C.10Bs then A.10Bs.

Wing span: 36.17 ft (10.42 m)
Overall length: 29.29 ft (8.9 m)
Height: 9.33 ft (2.8 m)
Wing area: 187.2 sq.ft (17.4 sq.m).
Wing aspect ratio: 6.22.
Empty wt: 4233 lb (1921 kg).
Normal T/O wt: 5842 lb (2652 kg).
MTOW: 7617 lb (3458 kg).
Internal fuel cap: 164 Imp.Gal. (745 lt).
External fuel cap: 106 Imp.Gal. (481 lt).
Wing loading: 31.2 lb/sq.ft (152 kg/sq.m).
Max speed: 435 mph (699 kph)
Initial ROC: 2755 fpm (14 m/sec)
TO dist 50 ft: 1740 ft (530 m)
Range: 930 sm (1496 km).

Hispano Aviation HA 200 D Saeta
Engine: 2 x Turboméca Marboré II A, 3924 N
Length: 29.429 ft / 8.97 m
Height: 10.696 ft / 3.26 m
Wingspan: 35.860 ft / 10.930 m
Max take off weight: 8048.3 lb / 3650.0 kg
Max. speed: 352 kt / 652 km/h
Service ceiling: 39370 ft / 12000 m
Range: 810 nm / 1500 km
Crew: 2

HA 200 R1
Engines: 2 x 880 lbs.t. (400 kgp) Turborneca Mabore IIA turbojets
Max speed, 435 mph (700 kph) at 22,966ft (7 000 m)
Cruise, 298 mph (480 kph)
Initial climb, 3,345 fpm. (17 m/sec)
Service ceiling, 41,000 ft (12 500 m)
Range, 1,056 mls (1 700 km)
Empty weight, 3,697 lb. (1677 kg)
Loaded weight, 6,305 lb (2 860 kg)
Span, 34ft 2.25 in (10.42 m)
Length, 29ft 1.5 in (8.88 m)
Wing area, 187.2 sq.ft (17,4 sq.m)

Hispano HS-42 / HA-43

HA-42

First flying in 1947, the Hispano HS-42 and its derivative, the HA-43, were advanced military trainer aircraft produced in Spain. The basic design was that of a conventional, low-wing, cantilever monoplane with seating for the pilot and instructor in tandem.

The HS-42 had fixed, tailwheel undercarriage with spatted mainwheels, while the HA-43 had retractable main units. Produced on the assembly line that had been used to build Fokker D.XXI fighters, the HS-42 shared some components with this aircraft.

HS-43 (HA-43)

The HA-43D-1 advanced two-seat military trainer went into production for the Spanish Air Force in 1947.

HS-42D

The HA-43D-1 was followed in 1953 by the HA-100 EI replacement

Gallery

HS-42
Engine: Piaggio Stella P.VII C.16
Fixed undercarriage

HA-43
Engine: Armstrong Siddeley Cheetah 27, 290 kW (390 hp)
Propeller: 2-bladed Rotol wooden variable-pitch
Propeller diameter: 2.84 m (9 ft 4 in)
Wingspan: 10.00 m (32 ft 10 in)
Wing area: 16.3 sq.m (175 sq ft)
Aspect ratio: 6.13:1
Length: 7.95 m (26 ft 1 in)
Height: 2.60 m (8 ft 6 in)
Empty weight: 1,504 kg (3,316 lb)
Gross weight: 2,050 kg (4,519 lb)
Fuel capacity: 400 L (110 US gal; 88 imp gal)
Maximum speed: 335 km/h (208 mph; 181 kn)
Cruise speed: 295 km/h (183 mph; 159 kn)
Stall speed: 118 km/h (73 mph; 64 kn) (flaps down)
Range: 1,200 km (746 mi; 648 nmi)
Endurance: 4 hr 15 min
Service ceiling: 6,000 m (20,000 ft)
Rate of climb: 7.2 m/s (1,410 ft/min)
Crew: 2
Guns: 2 × fixed, forward-firing 7.7 mm Breda-SAFAT machine guns in wings
Retractable undercarriage