The Bristol Jupiter was a British nine-cylinder single-row piston

radial engine The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders "radiate" outward from a central crankcase like the spokes of a wheel. It resembles a stylized star when viewed from the front, and is ...

built by the

Bristol Aeroplane Company The Bristol Aeroplane Company, originally the British and Colonial Aeroplane Company, was both one of the first and one of the most important British aviation companies, designing and manufacturing both airframes and aircraft engines. Notable a ...

. Originally designed late in

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was List of wars and anthropogenic disasters by death toll, one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, ...

and known as the Cosmos Jupiter, a lengthy series of upgrades and developments turned it into one of the finest engines of its era. The Jupiter was widely used on many aircraft designs during the 1920s and 1930s. Thousands of Jupiters of all versions were produced, both by Bristol and abroad under licence. A turbo-supercharged version of the Jupiter known as the Orion suffered development problems and only a small number were produced. The "Orion" name was later re-used by Bristol for an unrelated

turboprop A turboprop is a turbine engine that drives an aircraft propeller. A turboprop consists of an intake, reduction gearbox, compressor, combustor, turbine, and a propelling nozzle. Air enters the intake and is compressed by the compressor. ...

engine.

Design and development

The Jupiter was designed during

Roy Fedden Sir Alfred Hubert Roy Fedden MBE, FRAeS (6 June 1885 – 21 November 1973) was an engineer who designed most of Bristol Engine Company's successful piston aircraft engine designs. Early life Fedden was born in the Bristol area to fairly wealt ...

of Brazil Straker and later Cosmos Engineering. The first Jupiter was completed by Brazil Straker in 1918 and featured three carburettors, each one feeding three of the engine's nine cylinders via a spiral deflector housed inside the induction chamber. During the rapid downscaling of military spending after the war, Cosmos Engineering became bankrupt in 1920, and was eventually purchased by the

on the strengths of the Jupiter design and the encouragement of the

Air Ministry The Air Ministry was a department of the Government of the United Kingdom with the responsibility of managing the affairs of the Royal Air Force, that existed from 1918 to 1964. It was under the political authority of the Secretary of Stat ...

. The engine matured into one of the most reliable on the market. It was the first air-cooled engine to pass the Air Ministry full-throttle test, the first to be equipped with automatic boost control, and the first to be fitted to airliners. The Jupiter was fairly standard in design, but featured four valves per cylinder, which was uncommon at the time. The cylinders were machined from steel forgings, and the cast

cylinder head In an internal combustion engine, the cylinder head (often abbreviated to simply "head") sits above the cylinders and forms the roof of the combustion chamber. In sidevalve engines, the head is a simple sheet of metal; whereas in more modern o ...

s were later replaced with aluminium alloy following studies by the

Royal Aircraft Establishment The Royal Aircraft Establishment (RAE) was a British research establishment, known by several different names during its history, that eventually came under the aegis of the UK Ministry of Defence (MoD), before finally losing its identity in me ...

. In 1927, a change was made to move to a forged head design due to the rejection rate of the castings. The Jupiter VII introduced a mechanically-driven supercharger to the design, and the Jupiter VIII was the first to be fitted with reduction gears. In 1925, Fedden started designing a replacement for the Jupiter. Using a shorter stroke to increase the

revolutions per minute Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or with the notation min−1) is a unit of rotational speed or rotational frequency for rotating machines. Standards ISO 80000-3:2019 defines a unit of rotation as the dimensio ...

(rpm), and including a

supercharger 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 indu ...

for added power, resulted in the

Bristol Mercury The Bristol Mercury is a British nine-cylinder, air-cooled, single-row, piston radial engine. Designed by Roy Fedden of the Bristol Aeroplane Company it was used to power both civil and military aircraft of the 1930s and 1940s. Developed from ...

of 1927. Applying the same techniques to the original Jupiter-sized engine in 1927 resulted in the

Bristol Pegasus The Bristol Pegasus is a British nine-cylinder, single-row, air-cooled radial aero engine. Designed by Roy Fedden of the Bristol Aeroplane Company, it was used to power both civil and military aircraft of the 1930s and 1940s. Developed from th ...

. Neither engine would fully replace the Jupiter for a few years. In 1926 a Jupiter-engined Bristol Bloodhound with the registration G-EBGG completed an endurance flight of , during which the Jupiter ran for a total of 225 hours and 54 minutes without part failure or replacement.

Licensed production

The Jupiter saw widespread use in licensed versions, with fourteen countries eventually producing the engine. In France, Gnome-Rhone produced a version known as the Gnome-Rhône 9 Jupiter that was used in several local civilian designs, as well as achieving some export success. Siemens-Halske took out a licence in Germany and produced several versions of increasing power, eventually resulting in the

Bramo 323 The Bramo 323 ''Fafnir'' is a nine-cylinder radial aircraft engine of the World War II era. Based heavily on Siemens/Bramo's earlier experience producing the Bristol Jupiter under licence, the Bramo 323 saw limited use. Design and development ...

Fafnir, which saw use in German wartime aircraft. In Japan, the Jupiter was license-built from 1924 by Nakajima, forming the basis of its own subsequent radial aero-engine design, the Nakajima Ha-1 Kotobuki. It was produced in Poland as the PZL Bristol Jupiter, in Italy as the Alfa Romeo 126-RC35, and in

Czechoslovakia , rue, Чеськословеньско, , yi, טשעכאסלאוואקיי, , common_name = Czechoslovakia , life_span = 1918–19391945–1992 , p1 = Austria-Hungary , image_p1 ...

Walter Engines Walter Aircraft Engines is an aircraft engine manufacturer and former automotive manufacturer. Its notable products include the M601 turboprop. The company is based in Prague, Czech Republic. It has been a subsidiary of GE Aviation since July ...

. The most produced version was in the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...

, where its Shvetsov M-22 version powered the initial Type 4 version of the

Polikarpov I-16 The Polikarpov I-16 (russian: Поликарпов И-16) is a Soviet single-engine single-seat fighter aircraft of revolutionary design; it was the world's first low-wing cantilever monoplane fighter with retractable landing gear to attain o ...

(55 units produced). Type 4 Polikarpovs can be identified by their lack of exhaust stubs, rounded NACA cowling and lack of cowling shutters, features which were introduced on the

Shvetsov M-25 The Shvetsov M-25 was an aircraft radial engine produced in the Soviet Union (USSR) in the 1930s and 1940s, a licensed production variant of the Wright R-1820-F3. Design and development The first M-25s were produced from kits imported from th ...

powered Type 5 and later variants (total production 4,500+ units). Production started in 1918 and ceased in 1930.

Variants

The Jupiter was produced in many variants, one of which was the Bristol Orion of 1926.

Metallurgy Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys. Metallurgy encompasses both the sc ...

problems with this turbo-supercharged engine caused the project to be abandoned after only nine engines had been built. ;Brazil Straker (Cosmos) Jupiter I :(1918) ; only two engines assembled. ;Cosmos Jupiter II :(1918) ; a single engine assembled. ;Bristol Jupiter II :(1923) . ;Bristol Jupiter III :(1923) . BristolJupiter

;Bristol Jupiter IV :(1926) ; fitted with variable valve timing and a Bristol Triplex carburettor. ;Bristol Jupiter V :(1925) . ;Bristol Jupiter VI :(1927) ; produced in both high- (6.3:1) and low- (5.3:1)

compression ratio The compression ratio is the ratio between the volume of the cylinder and combustion chamber in an internal combustion engine at their maximum and minimum values. A fundamental specification for such engines, it is measured two ways: the stati ...

versions. ;Bristol Jupiter VIA :(1927) ; civil version of Jupiter VI. ;Bristol Jupiter VIFH :(1932) ; version of Jupiter VI equipped with gas starter motor. ;Bristol Jupiter VIFL :(1932) ; version of Jupiter VI with compression ratio of 5.15:1. ;Bristol Jupiter VIFM :(1932) ; version of Jupiter VI with compression ratio of 5.3:1. ;Bristol Jupiter VIFS :(1932) ; version of Jupiter VI with compression ratio of 6.3:1. ;Bristol Jupiter VII :(1928) ; fitted with supercharger, with compression ratio of 5.3:1; also manufactured by Gnome-Rhone as the 9ASB. ;Bristol Jupiter VIIF :(1929) ; version of Jupiter VII with forged cylinder heads. Bristol Jupiter VIIIF 2

;Bristol Jupiter VIIFP :(1930) ; version of Jupiter VII with pressure feed lubrication to wrist-pins. ;Bristol Jupiter VIII :(1929) ; first version with propeller reduction gearing; compression ratio 6.3:1. ;Bristol Jupiter VIIIF :(1929) ; version of Jupiter VIII with forged cylinder heads and lowered compression ratio (5.8:1). ;Bristol Jupiter VIIIFP :(1929) ; version of Jupiter VIII with pressure feed lubrication ( time between overhauls at this stage in development was only 150 hours due to multiple failures). ;Bristol Jupiter IX : ; compression ratio 5.3:1. ;Bristol Jupiter IXF : ; version of Jupiter IX with forged cylinder heads ;Bristol Jupiter X : ; compression ratio 5.3:1. ;Bristol Jupiter XF : ; version of Jupiter X with forged cylinder heads ;Bristol Jupiter XFA : ;Bristol Jupiter XFAM : ;Bristol Jupiter XFBM : ;Bristol Jupiter XFS :Fully supercharged. ;Bristol Jupiter XI :Compression ratio 5.15:1. ;Bristol Jupiter XIF : ; compression ratio 5.15:1. ;Bristol Jupiter XIFA : ; version of Jupiter XIF with 0.656:1 propeller gear reduction ratio ;Bristol Jupiter XIFP : ; version of Jupiter XIF with pressure feed lubrication. ;Bristol Orion I :(1926) Jupiter III, turbo-supercharged, abandoned programme. ;Gnome-Rhône 9A Jupiter:French licence production primarily of 9A, 9Aa, 9Ab, 9Ac, 9Akx and 9Ad variants. ; Siemens-Halske Sh20, Sh21 and Sh22: Siemens-Halske took out a licence in Germany and produced several versions of increasing power, eventually resulting in the

Bramo 323 Fafnir The Bramo 323 ''Fafnir'' is a nine-cylinder radial aircraft engine of the World War II era. Based heavily on Siemens/Bramo's earlier experience producing the Bristol Jupiter under licence, the Bramo 323 saw limited use. Design and development ...

, which saw use in wartime models. ; Nakajima Ha-1 Kotobuki: In Japan, the Jupiter was licence-built from 1924 by Nakajima. ;PZL Bristol Jupiter: Polish production. ; Alfa Romeo Jupiter: Italian licence production, . ;

Alfa 126 R.C.35 Alfa Romeo built/designed a range of aircraft engines based on the Bristol Jupiter and Bristol Pegasus designs, designated Alfa 125, Alfa 126, Alfa 127, Alfa 128, Alfa 129 and Alfa 131. All these essentially similar engines were mainly fitted ...

: Alfa Romeo developed variant ;Walter Jupiter: Licence production in Czechoslovakia by Walter Engines ;Shvetsov M-22: The most produced version; manufactured in the

. ;IAM 9AD Jupiter: Licence production of the Gnome-Rhône 9A in

Yugoslavia Yugoslavia (; sh-Latn-Cyrl, separator=" / ", Jugoslavija, Југославија ; sl, Jugoslavija ; mk, Југославија ;; rup, Iugoslavia; hu, Jugoszlávia; rue, label= Pannonian Rusyn, Югославия, translit=Juhoslavij ...

;SABCA Jupiter: license production in

Belgium Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to ...

by SABCA (''Société Anonyme Belge de Constructions Aéronautiques'') ;Piaggio-Jupiter: License production by Piaggio

Applications

The Jupiter is probably best known for powering the

Handley Page H.P.42 The Handley Page H.P.42 and H.P.45 were four-engine biplane airliners designed and manufactured by British aviation company Handley Page, based in Radlett, Hertfordshire. It held the distinction of being the largest airliner in regular use in ...

airliners, which flew the London-Paris route in the 1930s. Other civilian uses included the de Havilland Giant Moth and

de Havilland Hercules The de Havilland DH.66 Hercules was a 1920s British seven-passenger, three-engined airliner built by de Havilland Aircraft Company at Stag Lane Aerodrome. As a more modern replacement for the Airco DH.10 Amiens used on the RAF's airmail ser ...

, the Junkers G 31 and the huge

Dornier Do X The Dornier Do X was the largest, heaviest, and most powerful flying boat in the world when it was produced by the Dornier company of Germany in 1929. First conceived by Claude Dornier in 1924, planning started in late 1925 and after over 240, ...

flying boat, which used no less than twelve engines. Military uses were less common, but included the parent company's Bristol Bulldog, as well as the

Gloster Gamecock The Gloster Gamecock was a biplane fighter designed and produced by the British aircraft manufacturer Gloster. The Gamecock was a development of the earlier Grebe Mk III, an early interwar fighter procured by the Royal Air Force (RAF). Work ...

and Boulton Paul Sidestrand. It was also found in prototypes around the world, from Japan to Sweden. By 1929 the Bristol Jupiter had flown in 262 different aircraft types, ''Note:''

Cosmos Jupiter

* Bristol Badger *

Bristol Bullet The Bristol Type 32 Bullet was a British biplane racing aircraft. It was designed in 1919 by Frank Barnwell as a high-speed testbed for the Jupiter engine being developed in Bristol by Roy Fedden for the Cosmos Engineering company, and also ...

Sopwith Schneider The Sopwith Tabloid and Sopwith Schneider (floatplane) were British biplanes, originally designed as sports aircraft and later adapted for military use. They were among the first successful types to be built by the Sopwith Aviation Company. The ...

* Westland Limousine

Bristol Jupiter

* Aero A.32 *

Airco DH.9 The Airco DH.9 (from de Havilland 9) – also known after 1920 as the de Havilland DH.9 – was a British single-engined biplane bomber developed and deployed during the First World War. The DH.9 was a development of Airco's earlier successful ...

Arado Ar 64 The Arado Ar 64 was a single-seat biplane fighter, developed in the late 1920s. It was among the first fighters produced when Germany abandoned the restrictions of the Treaty of Versailles and began rearming. Design and development The Ar 6 ...

* Avia BH-25 * Avia BH-33E * Bernard 190 * Blériot-SPAD 51 * Blériot-SPAD S.56 * Boulton & Paul Bugle * Boulton Paul P.32 * Boulton Paul Partridge * Boulton Paul Sidestrand * Blackburn Beagle * Blackburn Nile * Blackburn Ripon * Bristol Badger * Bristol Badminton * Bristol Bagshot * Bristol Beaver * Bristol Bloodhound *

Bristol Boarhound The Bristol Boarhound was a British army cooperation and liaison aircraft of the 1920s. It was a two-seat biplane with wings of equal span, of steel frame construction with fabric covering. Design and development The Boarhound was built as a p ...

* Bristol Brandon * Bristol Bulldog * Bristol Bullfinch * Bristol Jupiter Fighter * Bristol Seely * Bristol Type 72 * Bristol Type 75 * Bristol Type 76 * Bristol Type 89 * Bristol Type 92 * Bristol Type 118 * de Havilland Dingo * de Havilland DH.72 * de Havilland DH.50 *

de Havilland Dormouse The de Havilland DH.42 Dormouse and its two variants the de Havilland DH.42A Dingo I and II were two-seat single-engined biplanes designed for fighter-reconnaissance and army cooperation roles. They did not achieve production. Development Apa ...

* de Havilland Hound * de Havilland Giant Moth * de Havilland Survey * Dornier Do 11 *

Dornier Do J The Dornier Do J ''Wal'' ("whale") is a twin-engine German flying boat of the 1920s designed by ''Dornier Flugzeugwerke''. The Do J was designated the Do 16 by the Reich Air Ministry (''RLM'') under its aircraft designation system of 1933. De ...

Fairey III The Fairey Aviation Company Fairey III was a family of British reconnaissance biplanes that enjoyed a very long production and service history in both landplane and seaplane variants. First flying on 14 September 1917, examples were still in u ...

F *

Fairey Ferret The Fairey Ferret was a 1930s British general-purpose biplane designed and built by the Fairey Aviation Company. It performed well in trials but was not ordered into production. Development The Ferret was designed to meet a Fleet Air Arm requ ...

* Fairey Flycatcher *

Fairey Hendon The Fairey Hendon was a British monoplane, heavy bomber of the Royal Air Force, designed by Fairey Aviation in the late 1920s. The aircraft served in small numbers with one squadron of the RAF between 1936 and 1939. It was the first all-metal lo ...

Fokker C.V The Fokker C.V was a Dutch light reconnaissance and bomber biplane aircraft manufactured by Fokker. It was designed by Anthony Fokker and the series manufacture began in 1924 at Fokker in Amsterdam. Development The C.V was constructed in the earl ...

* Fokker F.VIIA * Fokker F.VIII * Fokker F.IX * Gloster Gambet *

* Gloster Gnatsnapper * Gloster Goldfinch *

Gloster Goral The Gloster Goral was a single-engined two-seat biplane built to an Air Ministry contract for a general-purpose military aircraft in the late 1920s. It did not win the contest and only one was built. Development In 1927, driven by conflicting ...

* Gloster Goring * Gloster Grebe * Gloster Mars * Gloster Survey * Gourdou-Leseurre LGL.32 * Handley Page Clive * Handley Page Hampstead *

Handley Page Hare __NOTOC__ The Handley Page HP.34 Hare was a British two-seat high-altitude day bomber designed and built at Cricklewood by Handley Page. It was designed by Harold Boultbee to meet the requirements of Air Ministry Specification 23/25 for a repl ...

* Handley Page Hinaidi * Handley Page HP.12 *

Hawker Duiker The Hawker Duiker was an unusual and unsuccessful aircraft. It was the first design at Hawker under a new chief designer, Captain Thomson, in 1922. Much of the equipment and parts were proprietary and made by another aircraft company, Vickers, w ...

* Hawker Harrier * Hawker Hart *

Hawker Hawfinch The Hawker Hawfinch was a British single-engined biplane fighter of the 1920s. It was unsuccessful, with the Bristol Bulldog being selected instead. Development The Hawker Hawfinch fighter aircraft was designed in 1925 as a replacement for both ...

Hawker Hedgehog The Hawker Hedgehog was a three-seat reconnaissance biplane, to be used for naval scouting, produced to meet Air Ministry Specification 37/22. It was designed in 1923, and had its first flight the next year, piloted by F. P. Raynham. The crew ...

* Hawker Heron * Hawker Woodcock * Junkers F.13 * Junkers G 31 * Junkers W 34 *

Parnall Plover The Parnall Plover was a British single-seat naval fighter aircraft of the 1920s. Designed and built by George Parnall & Co. for use on Royal Navy aircraft carriers, it was ordered into small-scale production but after extensive evaluation, t ...

* PZL P.7 * Saunders Medina * Saunders Severn * Short Calcutta * Short Chamois * Short Gurnard *

Short Kent The Short S.17 Kent was a British four-engined 15-seat biplane luxury flying boat airliner, designed and built by Shorts to meet a requirement from Imperial Airways for an aircraft with greater range than the Short Calcutta. The new aircraft ...

Short Rangoon The Short S.8/8 Rangoon was a 1930s British three-engined biplane flying boat, designed and built by Short Brothers for the Royal Air Force. Background In 1929, the Royal Air Force needed urgent replacements of the Supermarine Southampton IIs ...

* Short Scylla *

Short Springbok The Short Springbok was a two-seat, all-metal reconnaissance biplane produced for the British Air Ministry in the 1920s. All together six aircraft of the Springbok design were built but none entered service with the armed forces. Design The Sp ...

* Short S.6 Sturgeon * Short Valetta * Supermarine Seagull *

Supermarine Solent Supermarine was a British aircraft manufacturer that is most famous for producing the Spitfire fighter plane during World War II as well as a range of seaplanes and flying boats, and a series of jet-powered fighter aircraft after World War II ...

* Supermarine Southampton *

Svenska Aero Jaktfalken Svenska Aero Jaktfalken ("Gyrfalcon") was a Swedish biplane fighter aircraft, constructed in the late 1920s. The aircraft was first manufactured by Svenska Aero and later by AB Svenska Järnvägsverkstädernas Aeroplanavdelning (ASJA). Hist ...

* Tupolev I-4 * Vickers F.21/26 * Vickers F.29/27 *

Vickers Jockey The Vickers Type 151 Jockey was an experimental low-wing monoplane interceptor fighter powered by a radial engine. It was later modified into the Type 171 Jockey II, which had a more powerful engine and detail improvements. Only one was built; ...

* Vickers Type 143 * Vickers Type 150 * Vickers Valiant *

Vickers Vellore The Vickers Vellore was a large biplane designed as a freight and mail carrier, in single-engined and twin-engined versions, which saw limited use as freighters and long-range experimental aircraft. A final variant with a broader fuselage, the ...

* Vickers Vellox *

Vickers Vespa The Vickers Vespa was a British army cooperation biplane designed and built by Vickers Limited in the 1920s. While not adopted by Britain's Royal Air Force, small numbers were bought by the Irish Free State and Bolivia, the latter of which used ...

Vickers Viastra The Vickers Viastra was an all-metal 12-seat passenger high-wing monoplane, with variants powered by one, two and three engines. Two twin-engined Viastras operated commercially in Australia from 1931-6; another served as a Royal transport. Deve ...

* Vickers Victoria * Vickers Vildebeest * Vickers Vimy * Vickers Vimy Trainer * Vickers Wibault Scout * Villiers 26 *

Westland Interceptor The Westland Interceptor was a fighter developed by the British company Westland Aircraft to Air Ministry Specification ''F.20/27''. When tested in 1929 and 1930, it showed unsatisfactory handling characteristics and was rejected by the RAF in ...

* Westland Wapiti * Westland Westbury * Westland Witch * Westland-Houston PV.3

Gnome-Rhône Jupiter

* Bernard SIMB AB 12 * Blanchard BB-1 * Breguet 19 * Fizir F1M-Jupiter * Latécoère 6 * Lioré et Olivier LeO H-15 * Potez 29/4 * Wibault Wib.220 * Denhaut Hy.479

Shvetsov M-22

* Kalinin K-5 * Kalinin K-12 * Polikarpov I-5 * Polikarpov I-15 *

* Tupolev I-4 * Yakovlev AIR-7

Engines on display

* A Bristol Jupiter VI is on static display at

Aerospace Bristol Aerospace Bristol is an aerospace museum at Filton, to the north of Bristol, England, U.K. The project is run by the Bristol Aero Collection Trust and houses a varied collection of exhibits, including Concorde ''Alpha Foxtrot'', the final Con ...

in the former Bristol Aeroplane Company factory complex in Filton, a suburb of Bristol, United Kingdom. * A Bristol Jupiter VIIF is on static display at the

Shuttleworth Collection The Shuttleworth Collection is a working aeronautical and automotive collection located at the Old Warden Aerodrome, Old Warden in Bedfordshire, England. It is the oldest in the world and one of the most prestigious, due to the variety of old ...

in Old Warden, United Kingdom. * A Bristol Jupiter VIIIF is on static display at the Steven F. Udvar-Hazy Center of the

National Air and Space Museum The National Air and Space Museum of the Smithsonian Institution, also called the Air and Space Museum, is a museum in Washington, D.C., in the United States. Established in 1946 as the National Air Museum, it opened its main building on the N ...

at Washington Dulles International Airport in Fairfax County, Virginia, United States. * A Bristol Bulldog complete with a Jupiter VIIFP engine is on static display at the Royal Air Force Museum London in Hendon, United Kingdom.

Specifications (Jupiter XFA)

References

Bibliography

* * Bridgman, L. (ed.) ''Jane's Fighting Aircraft of World War II''. New York: Crescent Books, 1998. * Lumsden, Alec. ''British Piston Engines and their Aircraft''. Marlborough, Wiltshire: Airlife Publishing, 2003. . * Gunston, Bill. ''Development of Piston Aero Engines''. Cambridge, England. Patrick Stephens Limited, 2006. * Gunston, Bill. ''World Encyclopedia of Aero Engines''. Cambridge, England. Patrick Stephens Limited, 1989.

External links

* Contemporary article on Cosmos Engineering's air-cooled radial engines. Photos of the Cosmos Jupiter are o
page 870
and a short technical description is o

{{Walter aeroengines Aircraft air-cooled radial piston engines

Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousand ...

1910s aircraft piston engines