The Liberty L-12 is an American water-cooled 45° V-12 aircraft engine displacing and making designed for a high

power-to-weight ratio Power-to-weight ratio (PWR, also called specific power, or power-to-mass ratio) is a calculation commonly applied to engines and mobile power sources to enable the comparison of one unit or design to another. Power-to-weight ratio is a measuremen ...

and ease of mass production. It saw wide use in aero applications, and, once

marinized Marinisation (also marinization) is design, redesign, or testing of products for use in a marine environment. Most commonly, it refers to use and long-term survival in harsh, highly corrosive salt water conditions. Marinisation is done by many manuf ...

, in marine use both in racing and runabout boats. A single bank 6-cylinder version, the

Liberty L-6 The Liberty L-6 was a six-cylinder water-cooled inline aircraft engine developed in the United States during World War I. Design and development The Liberty L-6, which developed 200–215 hp, was built by the Thomas-Morse Aircraft Corp. ...

, and V-8, the

Liberty L-8 The Liberty L-8 (also known as the Packard 1A-1100) was a prototype of the Liberty L-12 engine designed by Jesse Vincent and Elbert Hall. Fifteen L-8 prototypes were manufactured by several companies including Buick, Ford, Lincoln, Marmon, an ...

, were derived from the Liberty L-12. It was succeeded by the

Packard 1A-2500 The Packard 1A-2500 is an American V-12 liquid-cooled aircraft engine designed by Packard in 1924 as a successor to the World War I-era Liberty L-12. Five aero variants were produced, of which the 3A-2500 was the most numerous. Three marine ve ...

Development

In May 1917, a month after the United States had declared war on

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

, a federal task force known as the

Aircraft Production Board The Aircraft Board was a United States federal government organization created from the Aircraft Production Board on October 1, 1917, by Act of Congress to provide statutory authority to the APB, which had been created by a resolution of the Council ...

summoned two top engine designers,

Jesse G. Vincent Jesse Gurney Vincent (February 10, 1880 – April 20, 1962) was an American aircraft, marine, and automobile engine designer. Famed initially for his design of the World War I Liberty aircraft engine, he rose to enduring prominence as the longtim ...

(of the

Packard Packard or Packard Motor Car Company was an American luxury automobile company located in Detroit, Michigan. The first Packard automobiles were produced in 1899, and the last Packards were built in South Bend, Indiana in 1958. One of the "Thr ...

Motor Car Company of Detroit) and

Elbert J. Hall Elbert is a name that derived from the Germanic ''Alibert'' and may refer to: People Given name * Elbert Andrews (1901–1979), American baseball player * Elbert Adrain Brinckerhoff (1838–1913), American merchant and mayor * Egbert B. Brown (1 ...

(of the

Hall-Scott Hall-Scott Motor Car Company was an American manufacturing company based in Berkeley, California. It was among the most significant builders of water-cooled aircraft engines before World War I. History 1910–21 The company was founded in 1910 ...

Motor Co. in

Berkeley, California Berkeley ( ) is a city on the eastern shore of San Francisco Bay in northern Alameda County, California, United States. It is named after the 18th-century Irish bishop and philosopher George Berkeley. It borders the cities of Oakland and Emer ...

), to

Washington, D.C. ) , image_skyline = , image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morgan, ...

They were given the task of designing as rapidly as possible an aircraft engine that would rival if not surpass those of

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

, and Germany. The Board specified that the engine would have a high power-to-weight ratio and be adaptable to mass production. The Board brought Vincent and Hall together on 29 May 1917 at the

Willard Hotel The Willard InterContinental Washington, commonly known as the Willard Hotel, is a historic luxury Beaux-Arts hotel located at 1401 Pennsylvania Avenue NW in Downtown Washington, D.C. It is currently a member oHistoric Hotels of America the off ...

in Washington, where the two were asked to stay until they produced a set of basic drawings. After just five days, Vincent and Hall left the Willard with a completed design for the new engine, which had adopted, almost unchanged, the

single overhead camshaft An overhead camshaft (OHC) engine is a piston engine where the camshaft is located in the cylinder head above the combustion chamber. This contrasts with earlier overhead valve engines (OHV), where the camshaft is located below the combustion cha ...

and rocker arm valvetrain design of the later

Mercedes D.III The Mercedes D.III, or F1466 as it was known internally, was a six-cylinder SOHC valvetrain liquid-cooled inline aircraft engine built by Daimler and used on a wide variety of German aircraft during World War I. The initial versions were introd ...

a engines of 1917–18. In July 1917, an eight-cylinder prototype assembled by Packard's Detroit plant arrived in Washington for testing, and in August, the 12-cylinder version was tested and approved.

Production

In the fall of 1917, the

War Department War Department may refer to: * War Department (United Kingdom) * United States Department of War (1789–1947) See also * War Office, a former department of the British Government * Ministry of defence * Ministry of War * Ministry of Defence * Dep ...

placed an order for 22,500 Liberty engines, dividing the contract among the automobile and engine manufacturers

Buick Buick () is a division of the American automobile manufacturer General Motors (GM). Started by automotive pioneer David Dunbar Buick in 1899, it was among the first American marques of automobiles, and was the company that established General ...

Ford Ford commonly refers to: * Ford Motor Company, an automobile manufacturer founded by Henry Ford * Ford (crossing), a shallow crossing on a river Ford may also refer to: Ford Motor Company * Henry Ford, founder of the Ford Motor Company * Ford F ...

Cadillac The Cadillac Motor Car Division () is a division of the American automobile manufacturer General Motors (GM) that designs and builds luxury vehicles. Its major markets are the United States, Canada, and China. Cadillac models are distributed i ...

Lincoln Lincoln most commonly refers to: * Abraham Lincoln (1809–1865), the sixteenth president of the United States * Lincoln, England, cathedral city and county town of Lincolnshire, England * Lincoln, Nebraska, the capital of Nebraska, U.S. * Lincoln ...

, Marmon, and

in California was considered too small to receive a production order. Manufacturing by multiple factories was facilitated by its modular design. Ford was asked to supply cylinders for the new engine and rapidly developed an improved technique for cutting and pressing steel, which resulted in cylinder production rising from 151 per day to over 2,000; the company eventually manufactured all 433,826 cylinders produced, as well as 3,950 complete engines. Lincoln constructed a new plant in record time, devoted entirely to Liberty engine production, and assembled 2,000 engines in 12 months. By the time of the

Armistice with Germany The Armistice of 11 November 1918 was the armistice signed at Le Francport near Compiègne that ended fighting on land, sea, and air in World War I between the Entente and their last remaining opponent, Germany. Previous armistices ...

, the various companies had produced 13,574 Liberty engines, attaining a production rate of 150 engines per day. Production continued after the war, for a total of 20,478 engines built between July 4, 1917 and 1919. Although it is widely reported otherwise, a few Liberty engines did see action in France as power for the American version of the British

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. Air ...

Lincoln production

As the United States entered

World War I World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...

, the

division of General Motors was asked to produce the new Liberty aircraft engine, but

William C. Durant William Crapo Durant (December 8, 1861 – March 18, 1947) was a leading pioneer of the United States automobile industry and co-founder of General Motors and Chevrolet. He created a system in which a company held multiple marques – each s ...

was a

pacifist Pacifism is the opposition or resistance to war, militarism (including conscription and mandatory military service) or violence. Pacifists generally reject theories of Just War. The word ''pacifism'' was coined by the French peace campaign ...

who did not want General Motors or Cadillac facilities to be used for producing war material. This led to

Henry Leland Henry Martyn Leland (February 16, 1843 – March 26, 1932) was an American machinist, inventor, engineer and automotive entrepreneur. He founded the two premier American luxury automotive marques, Cadillac and Lincoln. Early years Henry M. Lelan ...

leaving Cadillac to form the Lincoln Motor Company to make Liberty engines. He quickly gained a $10,000,000 government contract to build 6,000 engines. Subsequently, the order was increased to 9,000 units, with an option for 8,000 more if the government needed them. (Durant later changed his mind and both Cadillac and Buick produced the engines.) More than 16,000 Liberty engines were produced during the calendar year 1918. To November 11, 1918, more than 14,000 Liberty engines were produced. Lincoln had delivered 6,500 of the V-12 overhead

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 ...

engines when production ceased in January 1919.

Design

The Liberty engine was a modular design where four or six cylinders could be used in one or two banks, allowing for inline fours, V-8s, inline sixes, or the V-12. The design was held together by a two-part cast aluminium

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 ...

. The two pieces formed the upper and lower halves of the completed assembly and were held together with a series of bolts running around the outside perimeter. As was common for the era, the cylinders were separately formed from forged steel tubes with thin metal jackets surrounding them to provide cooling water flow. A

for each cylinder bank operated two valves per cylinder, in an almost identical manner to the inline six-cylinder German

and

BMW III BMW IIIa was an inline six-cylinder SOHC valvetrain, water-cooled aircraft engine, the first-ever engine produced by Bayerische Flugzeugwerke AG, who, at the time, were exclusively an aircraft engine manufacturer. Its success laid the foundatio ...

engines. Each camshaft was driven by a vertical driveshaft that was placed at the back of each cylinder bank, again identical to the Mercedes and BMW straight-six powerplants.

Delco Electronics Delco Electronics Corporation was the automotive electronics design and manufacturing subsidiary of General Motors based in Kokomo, Indiana, that manufactured ''Delco'' Automobile radios and other electric products found in GM cars. In 1972, Gene ...

provided the

ignition system An ignition system generates a spark or heats an electrode to a high temperature to ignite a fuel-air mixture in spark ignition internal combustion engines, oil-fired and gas-fired boilers, rocket engines, etc. The widest application for spark ig ...

and

Zenith The zenith (, ) is an imaginary point directly "above" a particular location, on the celestial sphere. "Above" means in the vertical direction (plumb line) opposite to the gravity direction at that location (nadir). The zenith is the "highest" ...

the

carburetor 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 meteri ...

. Dry weight was 844 lb (383 kg). Fifty-two examples of a six-cylinder version, the

, which very closely resembled the Mercedes and BMW powerplants in overall appearance, were produced but not procured by the Army. A pair of the 52 engines produced were destroyed by William Christmas testing his so-called "

Christmas Bullet The Christmas Bullet, later known as the Cantilever Aero Bullet (sometimes referred to as the Christmas Strutless Biplane), was an American single-seat cantilever wing biplane. It is considered by many to be among the worst aircraft ever construc ...

" fighter.

Variants

;V-1650: An inverted Liberty 12-A referred to as the V-1650 was produced up to 1926 by Packard. The same designation was later applied to the

Packard V-1650 Merlin The Packard V-1650 Merlin is a version of the Rolls-Royce Merlin aircraft engine, produced under license in the United States by the Packard Motor Car Company.Gunston 1995, p. 144. The engine was licensed to expand production of the Rolls-Roy ...

, an engine with nearly identical

engine displacement Engine displacement is the measure of the cylinder volume swept by all of the pistons of a piston engine, excluding the combustion chambers. It is commonly used as an expression of an engine's size, and by extension as a loose indicator of the ...

. This was a

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

Packard produced version of the

Rolls-Royce Merlin The Rolls-Royce Merlin is a British liquid-cooled V-12 piston aero engine of 27-litres (1,650 cu in) capacity. Rolls-Royce designed the engine and first ran it in 1933 as a private venture. Initially known as the PV-12, it was later ...

, and is not to be confused with the earlier Liberty-based version. ;Allison VG-1410: The Allison VG-1410 was an air-cooled inverted Liberty L-12, with a geared super-charger, Allison

epicyclic An epicyclic gear train (also known as a planetary gearset) consists of two gears mounted so that the center of one gear revolves around the center of the other. A carrier connects the centers of the two gears and rotates the planet and sun gea ...

propeller reduction gear, and bore reduced to , giving a lower displacement of . ;Liberty L-6: A 6-cylinder version of the Liberty L-12, nicknamed the "Liberty Six", consisted of a single bank of cylinders, with the resulting engine bearing a strong external resemblance to both the

and

straight-six German aviation engines of World War I. ;Liberty L-8: An 8-cylinder V engine using Liberty cylinders in banks of four at 45°. ;Mikulin M-5:License production (or copies) produced in the USSR. ;Nuffield Liberty: Crusader tank III

The Nuffield Liberty tank engine was licensed and produced in World War II by the UK car manufacturer Nuffield. It was used in early

cruiser tank The cruiser tank (sometimes called cavalry tank or fast tank) was a British tank concept of the interwar period for tanks designed as modernised armoured and mechanised cavalry, as distinguished from infantry tanks. Cruiser tanks were develop ...

s, the Crusader, the

Cavalier The term Cavalier () was first used by Roundheads as a term of abuse for the wealthier royalist supporters of King Charles I and his son Charles II of England during the English Civil War, the Interregnum, and the Restoration (1642 – ). It ...

, and finally

Centaur A centaur ( ; grc, κένταυρος, kéntauros; ), or occasionally hippocentaur, is a creature from Greek mythology with the upper body of a human and the lower body and legs of a horse. Centaurs are thought of in many Greek myths as being ...

tanks. It was a 27 L (1,649 in³) engine with an output of , which was inadequate for the increasing vehicle weights as the war progressed and also suffered numerous problems with cooling and reliability. The Nuffield Liberty ran through multiple versions: * Mark I, US built engines modified in Britain. Modification incorporated new carburettors and a new induction system from

Solex Solex may refer to: * Solex (musician), Dutch musician * Solex Carburetor, a French manufacturer of carburetors and the powered bicycle VéloSoleX * Solex College, a former private for-profit college in Chicago, Illinois * Solex Unit, a fictiona ...

, revision of the crankcase breather, new timing gear, and revised crankshaft end thrust. This produced when governed to 1,500 rpm with the new carburettors. * Mark II, British built engines. The air compressor (for starting) was not used, and was removed on later engines * Mark III, IIIA and IIIB, made for the Crusader tank. This required a reduced height to fit in the engine bay, achieved by redesigning the oil pump and relocating the water pump. The air compressor was reinstated to enable pneumatically-operated braking and steering. Significant problems were experienced in desert use (the North African Campaign), and the Mk III went through multiple revisions. This included three different chain drive designs for the ancillary cooling fans, a revised valve adjustment mechanism, increased compression ratio, revised oil feeds, and two water pump replacements. * Mark IV, a revised design providing a shaft drive for cooling fans. This replaced the troublesome chain drive. This version also changed the air compressor to run at a lower speed. * Mark IVA, the power was increased to by increasing the governor limit to 1,700 rpm, and by fitting a new intake manifold and carburettor for the Cavalier tank. * Mark V, a redesigned engine producing the same power as the Mark IVA but for use in the Centaur tank. It revised the oil distribution in the engine, but remained governed to the higher speed of 1,700 rpm. The engine was intended for the

Cromwell tank The Cromwell tank, officially Tank, Cruiser, Mk VIII, Cromwell (A27M), was one of the series of cruiser tanks fielded by Britain in the Second World War. Named after the English Civil War-era military leader Oliver Cromwell, the Cromwell was th ...

, but the Liberty-based design was dropped in favour of the

Rolls-Royce Meteor The Rolls-Royce Meteor later renamed the Rover Meteor is a British tank engine that was developed during the Second World War. It was used in British tanks up to 1964. It was a result of co-operation between Leyland Motors and Rolls-Royce who betw ...

procured by the Tank Board. Those tanks fitted with Liberty were renamed Centaur, and production was split.

Applications

Aircraft

The primary use of the Liberty was in aircraft. *American-built versions of the

Airco DH.9A The Airco DH.9A was a British single-engined light bomber designed and first used shortly before the end of the First World War. It was a development of the unsuccessful Airco DH.9 bomber, featuring a strengthened structure and, crucially, repl ...

Airco DH.10 Amiens The Airco DH.10 Amiens was a twin-engined heavy bomber designed and produced by the British aircraft manufacturer Airco. It performed the first nighttime air mail service in the world on 14-15 May 1919. The DH.10 was developed in the final ye ...

Breguet 14 Breguet or Bréguet may refer to: * Breguet (watch), watch manufacturer **Abraham-Louis Breguet (1747–1823), Swiss watchmaker **Louis-François-Clement Breguet (1804–1883), French physicist, watchmaker, electrical and telegraph work * Bréguet ...

B2 L *

Caproni Ca.60 The Caproni Ca.60 Transaereo, often referred to as the Noviplano (nine-wing) or Capronissimo, was the prototype of a large nine-wing flying boat intended to become a 100-passenger transatlantic airliner. It featured eight engines and three sets ...

Curtiss H-16 The Curtiss Model H was a family of classes of early long-range flying boats, the first two of which were developed directly on commission in the United States in response to the £10,000 prize challenge issued in 1913 by the London newspaper, ...

Curtiss HS The Curtiss HS was a single-engined patrol flying boat built for the United States Navy during World War I. Large numbers were built from 1917 to 1919, with the type being used to carry out anti-submarine patrols from bases in France from June 1 ...

Curtiss NC The Curtiss NC (Curtiss Navy Curtiss, nicknamed "Nancy boat" or "Nancy") was a flying boat built by Curtiss Aeroplane and Motor Company and used by the United States Navy from 1918 through the early 1920s. Ten of these aircraft were built, the mos ...

Curtiss Carrier Pigeon The Curtiss Carrier Pigeon was an American mail plane of the 1920s. A single-engined biplane designed and built to replace World War I surplus aircraft such as the DH-4, the Carrier Pigeon was one of the first aircraft designed specifically for ...

Douglas C-1 The Douglas C-1 was a cargo/transport aircraft produced by the Douglas Aircraft Corporation for the United States Army Air Service starting in 1925. Design and development Douglas received an order for nine single-engined transport aircraft in 19 ...

Douglas DT The Douglas DT bomber was the Douglas Aircraft Company's first military contract, forging a link between the company and the United States Navy. Navy Contract No. 53305 of April 1, 1921, required only 18 pages to set out the specifications that ...

Douglas O-2 The Douglas O-2 was a 1920s American observation aircraft built by the Douglas Aircraft Company. Development The important family of Douglas observation aircraft sprang from two XO-2 prototypes, the first of which was powered by the 420 hp ...

Felixstowe F5L The twin-engine F5L was one of the Felixstowe F series of flying boats developed by John Cyril Porte at the Seaplane Experimental Station, Felixstowe, England, during the First World War for production in America. A civilian version of the airc ...

Fokker T.II The Fokker T.II or T.2 (Not to be confused with the Fokker T-2) was a single engine floatplane designed in the Netherlands in the early 1920s as a torpedo bomber. Three were bought by the US Navy who tested them against other aircraft from the ...

Handley Page H.P.20 The Handley Page H.P.20 was an experimental monoplane modification of a de Havilland DH.9A, built to study controllable slots and slotted ailerons as high lift devices. It was the first aircraft to fly with controllable slots. Development Fre ...

* Witteman-Lewis XNBL The engine was also used in the RN-1 (Zodiac) blimp.

Automobile

Based on aircraft use the engine provided a good power-to-weight ratio. This made it ideal for use in land speed attempt vehicles. It was selected for two land speed record attempts. * ''

Babs Babs or BABS may refer to: People * Nickname of Barbara Windsor (1937-2020), British actress * Babs McMillan, Australian actress * Babs Olusanmokun, American actor * Babs Reingold, American artist * Babs Fafunwa (1923-2010), Nigerian educationist ...

'', a single engined vehicle *

White Triplex The White Triplex (also known as the "Triplex Special" and the "Spirit of Elkdom") was an American land speed record car built for J. H. White and driven by Ray Keech. It was powered by three 27-litre Liberty aero engines, for a total of 36 cyli ...

, mounting three Liberty engines working in tandem Both attempts set new records. Both crashed during further attempts, resulting in the deaths of the drivers and a newsreel cameraman.

Tank

As early as 1917 the Liberty showed good potential for use in tanks as well as aircraft. The Anglo-American, or "Liberty", Mark VIII tank was designed in 1917–18. The American version used an adaptation of the Liberty V-12 engine of 300 hp (220 kW), designed to use

cast iron Cast iron is a class of iron–carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuriti ...

cylinders rather than drawn

steel Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...

ones. One hundred tanks were manufactured at the

Rock Island Arsenal The Rock Island Arsenal comprises , located on Arsenal Island, originally known as Rock Island, on the Mississippi River between the cities of Davenport, Iowa, and Rock Island, Illinois. It lies within the state of Illinois. Rock Island ...

in 1919–20, too late for

. They were eventually sold to Canada for training in 1940, except for two that have been preserved. Inter-war,

J. Walter Christie John Walter Christie (May 6, 1865 – January 11, 1944) was an American engineer and inventor. He is best known for developing the Christie suspension system used in a number of World War II-era tank designs, most notably the Soviet BT and T-34 ...

combined aircraft engines with new suspension design, producing a rapid and highly mobile tank. Using Christie's concept, Russian forces selected and copied the Liberty in the BT-2 & BT-5 Soviet interwar tank (at least one reconditioned Liberty was installed in a BT-5). Demonstration of this tank was witnessed by the British, and Christie's design characteristics were licensed and incorporated into the British A13 design specification. As

loomed, Nuffield, producing British

s, licensed and re-engineered the Liberty for use in the A13 (produced as the

Cruiser Mk III The Tank, Cruiser, Mk III, also known by its General Staff specification number A13 Mark I, was a British cruiser tank of the Second World War. It was the first British cruiser tank to use the Christie suspension system, which gave higher speeds ...

) and later cruiser tanks, with an output of 340 hp (410 hp from the Mark IV version). In later British tanks it was replaced by the

, an engine based on the

aero engine, which offered greater engine power (600 hp). Nuffield Liberty engines were used in British tanks of immediate pre-war and Second World War: *

(A13 Mark I) – Nuffield Liberty Mk I *

Cruiser Mk IV } The Cruiser Tank Mk IV ( A13 Mk II) was a British cruiser tank of the Second World War. It followed directly on from the Tank, Cruiser, Mk III (A13 Mk I). The first Mk IVs were Mk IIIs with extra armour fitted to the turret. Later Mk IVAs we ...

(A13 Mark II) – Nuffield Liberty Mk II *

Crusader tank Crusader, in full "Tank, Cruiser Mk VI, Crusader", also known by its General Staff number A.15, was one of the primary British cruiser tanks during the early part of the Second World War. Over 5,000 tanks were manufactured and they made imp ...

– Nuffield Liberty Mk III, IIIA, IIIB, or IV *

Cavalier tank The Tank, Cruiser, Mk VII Cavalier (A24) was an interim design of British cruiser tank during the Second World War. It was derived from the A15 Crusader tank and was superseded by the A27 Cromwell tank. Development Early Development Deve ...

– Nuffield Liberty Mk IVA *

Centaur tank A centaur ( ; grc, κένταυρος, kéntauros; ), or occasionally hippocentaur, is a creature from Greek mythology with the upper body of a human and the lower body and legs of a horse. Centaurs are thought of in many Greek myths as being ...

– a parallel version of the

Meteor A meteoroid () is a small rocky or metallic body in outer space. Meteoroids are defined as objects significantly smaller than asteroids, ranging in size from grains to objects up to a meter wide. Objects smaller than this are classified as micr ...

-engined

Cromwell Oliver Cromwell (25 April 15993 September 1658) was an English politician and military officer who is widely regarded as one of the most important statesmen in English history. He came to prominence during the 1639 to 1651 Wars of the Three Ki ...

British World War II tank – Nuffield Liberty Mk V

Watercraft

''HD-4'' or ''Hydrodome number 4'' was an early research

hydrofoil A hydrofoil is a lifting surface, or foil, that operates in water. They are similar in appearance and purpose to aerofoils used by aeroplanes. Boats that use hydrofoil technology are also simply termed hydrofoils. As a hydrofoil craft gains sp ...

watercraft developed by the scientist

Alexander Graham Bell Alexander Graham Bell (, born Alexander Bell; March 3, 1847 – August 2, 1922) was a Scottish-born inventor, scientist and engineer who is credited with patenting the first practical telephone. He also co-founded the American Telephone and Te ...

. In 1919, it set a world marine speed record of powered by two 350 hp Liberty L-12s. Miss America 2 1921

Inventor, entrepreneur, and boat racer

Gar Wood Garfield Arthur "Gar" Wood (December 4, 1880 – June 19, 1971) was an American inventor, entrepreneur, and championship motorboat builder and racer who held the world water speed record on several occasions. He was the first man to travel ...

set a new water speed record of in 1920 in a new twin Liberty V-12 powered boat called ''Miss America''. In the following twelve years, Wood built nine more Packard V-12 driven ''Miss Americas'' and broke the record five times, raising it to . He also won five straight powerboat Gold Cup races between 1917 and 1921, and the prestigious

Harmsworth Trophy The Harmsworth Cup, popularly known as the Harmsworth Trophy, is a historically important British international trophy for motorboats. History The Harmsworth was the first annual international award for motorboat racing. Officially, it is a cont ...

nine times between 1920 and 1933, at the helm of his ''Miss Americas''. Many gentlemen's runabouts, Gold Cup, and other race-winners were built with Liberty L-12 engines.

Survivors

A number of Liberty engines survive in restored operational and static display vehicles. Displays of the engine itself include: ;Australia * A Liberty 12 from a DH.9A is on display at the

Australian Aviation Heritage Centre The Darwin Aviation Museum, previously known as the Australian Aviation Heritage Centre, displays aircraft and aircraft engines of relevance to the Northern Territory and aviation in Australia generally. It is located in Darwin suburb of Winne ...

in Darwin, Northern Territory ;United Kingdom * A Nuffield Liberty is on display at

The Tank Museum The Tank Museum (previously The Bovington Tank Museum) is a collection of armoured fighting vehicles at Bovington Camp in Dorset, South West England. It is about north of the village of Wool and west of the major port of Poole. The collection ...

, Bovington ;United States * A 12A is on display at the

New England Air Museum The New England Air Museum (NEAM) is an American aerospace museum located adjacent to Bradley International Airport in Windsor Locks, Connecticut. The museum consists of three display hangars with additional storage and restoration hangars. Its c ...

Bradley International Airport Bradley International Airport is a public international airport in Windsor Locks, Connecticut, United States. Owned and operated by the Connecticut Airport Authority, it is the second-largest airport in New England. The airport is about halfw ...

Windsor Locks Windsor Locks is a town in Hartford County, Connecticut, United States. As of the 2020 census, its population was 12,613. It is the site of Bradley International Airport, which serves the Greater Hartford-Springfield region and occupies approxim ...

, Connecticut. * An operable Liberty V-12 on a static test stand trailer is often run for demonstrations at

Old Rhinebeck Aerodrome The Old Rhinebeck Aerodrome is a living museum in Rhinebeck, New York. It owns many examples of airworthy aircraft of the Pioneer Era, World War I and the Golden Age of Aviation between the World Wars, and multiple examples of roadworthy antiqu ...

's weekend airshow events. * A Packard Liberty V-1650 Aircraft engine (cut-away)- 12 cylinder "v" type water cooled engine; 400 h.p. at 1700 r.p.m. 5" bore, 7" stroke, 8431 lbs., 45-degree angle cylinders, and aluminum pistons is on exhibit on a display stand at

Carillon Historical Park Carillon Historical Park is a 65-acre (26.3 ha) park and museum in Dayton, Ohio, which contains historic buildings and exhibits concerning the history of technology and the history of Dayton and its residents from 1796 to the present. As a part of ...

in Dayton, Ohio.

Specifications

References

Notes

Bibliography

* Bradford, Francis H. Hall-Scott: The Untold Story of a Great American Engine Manufacturer * Angelucci, Enzo. ''The Rand McNally Encyclopedia of Military Aircraft, 1914–1980.'' San Diego, California: The Military Press, 1983. . * Barker, Ronald and Anthony Harding. ''Automotive Design: Twelve Great Designers and Their Work.'' SAE, 1992. . * Leland, Mrs. Wilfred C. and Minnie Dubbs Millbrook. ''Master of Precision: Henry M. Leland.'' Detroit, Michigan: Wayne State University Press, 1996. . * Lewis, David L. ''100 Years of Ford.'' Lincolnwood, Illinois: Publications International. 2005. .
"Lincolns."
''Lincoln Anonymous''. Retrieved: August 22, 2006. * Vincent, J.G. ''The Liberty Aircraft Engine.'' Washington, D.C.: Society of Automotive Engineers, 1919. * Weiss, H. Eugene. ''Chrysler, Ford, Durant and Sloan: Founding Giants of the American Automotive Industry.'' Jefferson, North Carolina: McFarland & Company, 2003. .

External links

Annals of Flight
*
Old Rhinebeck Aerodrome's operable Liberty V-12 engine run video
{{US military piston aeroengines 1910s aircraft piston engines

Liberty Liberty is the ability to do as one pleases, or a right or immunity enjoyed by prescription or by grant (i.e. privilege). It is a synonym for the word freedom. In modern politics, liberty is understood as the state of being free within society fr ...

V12 aircraft engines