The Sunbeam Cossack was a British 12-cylinder

aero engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years many ...

that was first run in 1916. The Cossack spawned a family of engines from Sunbeam.

Design and development

As the First World War raged through 1914 and 1915, The Admiralty demanded engines with more power for its existing and future aircraft. The problem was exemplified by the Short Type 184 seaplanes of the

RNAS The Royal Naval Air Service (RNAS) was the air arm of the Royal Navy, under the direction of the Admiralty's Air Department, and existed formally from 1 July 1914 to 1 April 1918, when it was merged with the British Army's Royal Flying Corps t ...

, powered by

Sunbeam Mohawk The Sunbeam Crusader, originally known as the Sunbeam 150 hp, Sunbeam 110 hp or Sunbeam 100 hp (variations on the engine may also have been referred to as Sunbeam 120 hp or Sunbeam 135 hp), was an early British, side-va ...

engines, which could barely lift the standard air-dropped torpedo with crew reduced to two and minimal fuel. An engine with a base rating of at least was demanded by the Admiralty. Responses came from Rolls-Royce with the

Rolls-Royce Eagle The Rolls-Royce Eagle was the first aircraft engine to be developed by Rolls-Royce Limited. Introduced in 1915 to meet British military requirements during World War I, it was used to power the Handley Page Type O bombers and a number of oth ...

and Sunbeam with the Sunbeam Cossack. Louis Coatalen designed the Cossack as a twin overhead camshaft 60° V-12, with four valves per cylinder, bore of and stroke of . Output from the Cossack was at 2,000rpm, with a running weight of , driving a large diameter propeller through a 2:1 reduction gear. Construction of the Cossack was largely of aluminium alloy with cast-iron cylinder blocks and integral heads in groups of three. Large orders were placed for the Cossack but deliveries were very slow, with only eleven, largely hand-built, engines delivered from March 1916 to September 1916. The end of Sunbeam Gurkha production in October 1916 freed up factory resources to allow up to thirty engines a month to be delivered until Cossack production ended in December 1917 after 350 deliveries. Development of the basic engine produced the Sunbeam Cossack II with four magnetos, to counter the unreliability of British contemporary magnetos, and a compressed-air or hand driven starter, rated at . Late in the First World War Britain's airship aspirations were boosted by the order for the R36, R37 and

R38 The ''R.38'' class (also known as the ''A'' class) of rigid airships was designed for Britain's Royal Navy during the final months of the First World War, intended for long-range patrol duties over the North Sea. Four similar airships were ...

. All three airships were powered a variety of engines including the Sunbeam Cossack III a derivative of the Cossack with a flywheel, hand or air starter, engine controls and magnetos mounted directly on the engine for access by the engine mechanics. The Cossack 3 was designed with a water-cooled exhaust and speed governor. The overhead camshaft was gear driven from the crankshaft.''Flight'' 8 July 1920 p732
/ref> Only 14 Cossack IIIs were built due to the cancellation of the post-war British airships.

Amazon

In similar fashion to other engine families designed by Coatalen the Cossack spawned a straight-six derivative in the Amazon, in effect half a Cossack, retaining the 110 x 160mm bore/stroke, overhead camshaft, four poppet valves per cylinder and cast-iron cylinder blocks in groups of three. An output of from for a running weight of led to a high power to weight ratio. Despite the high output the Amazon was little used in Britain, with only possible use aboard Coastal airships and some supplied to the

Imperial Russian Air Service The Imperial Russian Air Service (russian: Императорскій военно-воздушный флотъ, , Emperor's Military Air Fleet) was an air force founded in 1912 for Imperial Russia."''12 августа 1912 года прика ...

. Amazon production totalled 77 out of an order for 100, 23 of which were cancelled. A non-aviation use version of the Amazon was produced as the Sunbeam Amazon II, fitted with hand and/or compressed-air starters and single magneto ignition system.

Saracen

Development paths favoured by Coatalen included increasing the bore and Aluminium alloy cylinder blocks. Aluminium alloy cylinder blocks and the bore increased to , the capacity increased to to produce the Sunbeam Saracen straight-six. Delivering at 2,000 rpm, driving a propeller through a 2:1 reduction gear. When submitted to the Internal Combustion Engine Committee of the

National Advisory Committee for Aeronautics The National Advisory Committee for Aeronautics (NACA) was a United States federal agency founded on March 3, 1915, to undertake, promote, and institutionalize aeronautical research. On October 1, 1958, the agency was dissolved and its assets ...

the Saracen faced stiff competition from the

Beardmore 160 hp The Beardmore 160 hp is a British six-cylinder, water-cooled aero engine that first ran in 1916, it was built by Arrol-Johnston and Crossley Motors for William Beardmore and Company as a development of the Beardmore 120 hp, itself a licens ...

and

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 ...

and did not attract any orders. Only prototypes of the Saracen were built.

Viking

To extract more power from the Cossack lineage Coatalen designed a W-18 version known as the Sunbeam Viking. This engine used Cossack blocks in a W arrangement with 60° between banks having a capacity of giving at a propeller speed of 900 rpm. Orders for 50 engines were received, intended to power the large

AD Seaplane Type 1000 The AD Seaplane Type 1000 also known as the Admiralty Type 1000 and the AD.1 (from Air Department) was a British seaplane of the First World War designed to attack German warships. When it first flew, it was the largest British aircraft yet to ...

aircraft, but most of the nine engines produced were fitted to motor boats, the remaining 41 being cancelled.

Matabele

The final fling of the Cossack family was the Sunbeam Matabele, retaining the Aluminium alloy blocks and bore of the Saracen the V-12 Matabele delivered at 2,000rpm through a 1.63:1 reduction gear from . Developed in two versions, the Sunbeam Matabele I, for aviation use, was fitted with four magnetos to provide redundancy for the dual ignition system, whilst the Sunbeam Matabele II was only fitted with two magnetos supplying a single ignition system for non-aviation use. Used mainly in

Airco DH.4 The Aircraft Manufacturing Company Limited (Airco) was an early British aircraft manufacturer. Established during 1912, it grew rapidly during the First World War, referring to itself as the largest aircraft company in the world by 1918. Ai ...

bombers, the Matabele also found favour as a power-boat and speed-record car engine. No Matabeles were built during the First World War, but prototypes and at least eight production engines were built after the war for various applications.

''Sunbeam 1000 hp''

The Matabele engine is best known today for powering the

Sunbeam 1000 hp The Sunbeam 1000 HP ''Mystery'', or "''The Slug''", is a land speed record-breaking car built by the Sunbeam car company of Wolverhampton that was powered by two aircraft engines. It was the first car to travel at over 200 mph. The car's la ...

land speed record car, the first car to exceed 200 mph. After taking the land speed record at with the Sunbeam Tiger, Segrave realised that his small, lightweight racing car would be inadequate to hold the record against the aero-engined

leviathan Leviathan (; he, לִוְיָתָן, ) is a sea serpent noted in theology and mythology. It is referenced in several books of the Hebrew Bible, including Psalms, the Book of Job, the Book of Isaiah, the Book of Amos, and, according to some ...

s now appearing in the contest. The S.T.D. Motors team was short of funds and so little new development was possible. A pair of Matabele engines were found in the Sunbeam works at

Wolverhampton Wolverhampton () is a city, metropolitan borough and administrative centre in the West Midlands, England. The population size has increased by 5.7%, from around 249,500 in 2011 to 263,700 in 2021. People from the city are called "Wulfrunians ...

, previously from the ill-fated '' Maple Leaf VII'' powerboat. As the Sunbeam 1000 HP is reported as having 4 magnetos per engine,National Motor Museum guidebook, Beaulieu these would appear to be Matabele I, rather than Matabele II engines. On 29 March 1927, the Sunbeam became the first car to exceed 200 mph. Although loudly trumpeted as the "1000 HP" Sunbeam, the actual power was somewhere around 900 bhp. The installation of these engines was somewhat unorthodox, necessitated by the limited funds for new work. The rear engine was started first by compressed air starting, then the front engine was started through a mechanical friction clutch. Once synchronised, they were locked together with a

dog clutch A dog clutch (also known as a positive clutch or dog gears) is a type of clutch that couples two rotating shafts or other rotating components by engagement of interlocking teeth or dogs rather than by friction. The two parts of the clutch are de ...

for the record attempt. The car's last run was a demonstration circuit at

Brooklands Brooklands was a motor racing circuit and aerodrome built near Weybridge in Surrey, England, United Kingdom. It opened in 1907 and was the world's first purpose-built 'banked' motor racing circuit as well as one of Britain's first airfields ...

, running at slow speed on only one engine, with this dog clutch disconnected.

Variants

;Cossack I :The basic production V-12 engine with cast-iron blocks, bore and single ignition system fed by two magnetos. Rated at at 2,000rpm. ;Cossack II :An improved Cossack with dual ignition system and hand / compressed air starter. Rated at at 2,000rpm. ;Cossack 3 :Built for airship use. Produced 350 hp at 2,000 rpm and weighed dry. ;Amazon :A straight six version of the Cossack retaining the dual ignition system, bore and stroke and cast-iron blocks in groups of three. Rated at at 2,000rpm. ;Amazon II :A non-aviation use version of the Amazon with single ignition system. Rated at at 2,000 rpm. ;Saracen :In the Saracen, Coatalen increased the bore to and changed construction to Aluminium alloy blocks. Rated at at 2,000 rpm the Saracen failed to gain any orders, only prototypes being built. ;Viking :The Viking was a W-18 using the blocks of the Cossack and retaining its attributes. Intended for the AD.1000 floatplane for the

. Production of the 50 ordered was halted after nine had been built; those not used in the sole AD.1000 built were fitted to motor-boats. ;Matabele I :The Matabele I was a v-12 engine with similar aluminium alloy blocks to the Saracen, as well as the larger bore of , rated at at 2,000 rpm. Intended for general aviation use the Matabele I had a dual ignition system with four magnetos. ;Matabele II :For non-aviation use the Matabele II had a single ignition system and compressed-air / hand starters. This engine found favour powering motor-boats.

Applications

(Cossack and Viking) * Short Type 310 (Cossack) * Porte Baby FB.2 (Cossack) *

Felixstowe F.3 The Felixstowe F.3 was a British First World War flying boat, successor to the Felixstowe F.2 designed by Lieutenant Commander John Cyril Porte RN at the naval air station, Felixstowe. Design and development In February 1917, the first pro ...

(Cossack) * Handley Page Type O/400 (Cossack) *

Tellier Flying boat Tellier is a surname, and may refer to: * Charles Tellier (1828–1913), French compressed air engineer * Joseph-Mathias Tellier (1861–1952), Quebec Conservative Party * Léon Tellier, French Olympic sailor * Lionel Tellier (1905–1973), Cana ...

(Cossack) * HM Airship R36 (Cossack III) * HM Airship R37 (Cossack III) Airship scrapped when 95% complete * HM Airship R38 (Cossack III) (R38 class discontinued) *

Coastal class blimp __NOTOC__ The Coastal Class (often known as the C-Class or simply the 'Coastals') were a class of non-rigid airship or "blimp" used by the Royal Naval Air Service (RNAS) during World War I. The C-class blimp operated by the United States Navy ...

C-14 (Amazon?) * Thorneycroft Coastal motor-boats (Viking) *

(Matabele II) * Sunbeam Despujois I – motor boat (Matabele II) * Sunbeam Despujois II – motor boat (Matabele II) * Sunbeam Despujois IV – motor boat (Matabele II) * Sunbeam Despujois V – motor boat (Matabele II) * '' Maple Leaf VII'' – Sir

Edward Mackay Edgar Sir Edward Mackay Edgar, 1st Baronet (27 February 1876 – 7 October 1934) was a Canadian-British banker. Mackay Edgar was born in Montreal and educated at McGill University. He became a member of the Montreal Stock Exchange. In 1907 he went to Br ...

's 1921 Saunders- built motor boat (Matabele II) *

– speed record breaking car (Matabele I)

Specifications (Cossack II)

References

Bibliography

* * Lumsden, Alec. ''British Piston Engines and their Aircraft''. Marlborough, Wiltshire: Airlife Publishing, 2003. . * Brew, Alec. ''Sunbeam Aero-Engines''. Airlife Publishing. Shrewsbury.

External links

Sunbeam Overhead Cam Engines
{{Sunbeam aeroengines

Cossack The Cossacks , es, cosaco , et, Kasakad, cazacii , fi, Kasakat, cazacii , french: cosaques , hu, kozákok, cazacii , it, cosacchi , orv, коза́ки, pl, Kozacy , pt, cossacos , ro, cazaci , russian: казаки́ or ...

1910s aircraft piston engines