The de Havilland Gipsy is a British air-cooled four-cylinder in-line aircraft engine designed by

Frank Halford Major Frank Bernard Halford CBE FRAeS (7 March 1894 – 16 April 1955) was an English aircraft engine designer. He is best known for the series of de Havilland Gipsy engines, widely used by light aircraft in the 1920s and 30s. Career Educat ...

in 1927 to replace the

ADC Cirrus The ADC Cirrus is a series of British aero engines manufactured using surplus Renault parts by the Aircraft Disposal Company (ADC) in the 1920s. The engines were air-cooled, four-cylinder inline types. They were widely used for private and li ...

in the

de Havilland DH.60 Moth The de Havilland DH.60 Moth is a 1920s British two-seat touring and training aircraft that was developed into a series of aircraft by the de Havilland Aircraft Company. Development The DH.60 was developed from the larger DH.51 biplane. ...

light biplane. Initially developed as an upright 5 litre (300 cubic inch) capacity engine, later versions were designed to run inverted with increased capacity and power. The Gipsy went on to become one of the most popular sport aircraft engines of the inter-war period and was the engine of choice for various other

light aircraft A light aircraft is an aircraft that has a maximum gross takeoff weight of or less.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 308. Aviation Supplies & Academics, 1997. Light aircraft are used as utility aircraft c ...

trainers Sneakers (also called trainers, athletic shoes, tennis shoes, gym shoes, kicks, sport shoes, flats, running shoes, or runners) are shoes primarily designed for sports or other forms of physical exercise, but which are now also widely used f ...

liaison aircraft A liaison aircraft (also called an army cooperation aircraft) is a small, usually unarmed aircraft primarily used by military forces for artillery observation or transporting commanders and messages. The concept developed before World War II and ...

and air taxis, British as well as foreign, until long past World War II. Apart from helping to establish the

de Havilland Aircraft Company The de Havilland Aircraft Company Limited () was a British aviation manufacturer established in late 1920 by Geoffrey de Havilland at Stag Lane Aerodrome Edgware on the outskirts of north London. Operations were later moved to Hatfield in H ...

as a manufacturer of light aircraft, it also established the company as an engine manufacturer in its own right. Gipsy engines remain in service powering vintage light aircraft.

Design and development

Just like the ADC Cirrus, the Gipsy was born as a collaboration between aircraft manufacturer

Geoffrey de Havilland Captain Sir Geoffrey de Havilland, (27 July 1882 – 21 May 1965) was an English aviation pioneer and aerospace engineer. The aircraft company he founded produced the Mosquito, which has been considered the most versatile warplane ever built,D ...

and engine designer

. In fact, the early history of the Cirrus and Gipsy were linked through de Havilland's D.H.60 Moth.

Cirrus origins

In 1925 Geoffrey de Havilland was looking for a reliable cheap engine for use in a light sports aircraft. More particularly, he was looking for something like his favourite First World War aircraft engine: the

Renault 8G The Renault 8G was a family of French liquid-cooled V-8 aero engines of the World War I era that produced from to . Design and development Construction used separate cast iron blocks for each pair of cylinders, mounted on a light-alloy crankc ...

air-cooled V8, but with half the weight and half the power. Halford gave it to him by building a four-cylinder crankcase and adding to it half of the Renault's cylinders, several other of the Renault's components, and standard parts used in car engines. The result was a in-line aircraft engine that, although it fell short of the promised horse-power, was still superior to all contemporary engines for light aircraft. Most importantly it was a true aircraft engine at a time where its competitors were more often than not motorcycle engines adapted to running at high altitude. The engine secured, de Havilland Aircraft commenced manufacture of the D.H.60 Moth and the combination of reliable powerplant – the

– and reliable training craft – the Moth – marked the start of serious sports flying in Britain. By 1927 however, the Moth threatened to become a victim of its own success as continuing demand was depleting the stockpiles of surplus Renaults needed to build its Cirrus engine. The Moth now having provided a solid financial cushion, de Havilland Aircraft decided to take the problem head-on and start its own engine factory. Geoffrey de Havilland again went to his old friend Halford and this time asked him to design a completely new aircraft engine of weight and performance comparable to the latest version of the Cirrus, the

Cirrus Hermes The Cirrus and Hermes or Cirrus-Hermes are a series of British aero engines manufactured, under various changes of ownership, from the 1920s until the 1950s. The engines were all air-cooled, four-cylinder inline types, with earlier ones upright an ...

DH.71 Tiger Moth racer

Halford and de Havilland quickly agreed on a test engine later to be de-rated to for production models. While Halford went to build the engine, de Havilland designed its test-bed: the diminutive D.H.71 racer.Bransom 1991, p.25. Two D.H.71s were built and although in a bout of over-confidence named Tiger Moth, their racing career was rather uneventful. Their only notable claim to fame came in capturing a world speed record of for their weight class. (The name Tiger Moth would later be used again for the D.H.82 trainer and with this aircraft gain more than its share of fame.) What the D.H.71 did not accomplish in racing successes, it did accomplish in developing the new engine and by the time the career of the D.H.71 was over, the production version of its engine, now named the Gipsy, was ready to start its career.

Technical description

Like the Cirrus, the new Gipsy was an air-cooled four-cylinder in-line engine weighing a mere 300 pounds and rated at 98 hp (73 kW) at 2,100 rpm. The cylinders had a

bore Bore or Bores often refer to: *Boredom * Drill Relating to holes * Boring (manufacturing), a machining process that enlarges a hole ** Bore (engine), the diameter of a cylinder in a piston engine or a steam locomotive ** Bore (wind instruments), ...

of and a

stroke A stroke is a medical condition in which poor blood flow to the brain causes cell death. There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functionin ...

of for a displacement of . It was soon developed further into the Gipsy II; both types were to be used in the D.H.60G Gipsy Moth. The new engine proved itself to be docile, easy to maintain and, as demonstrated in many long distance flights by the new Gipsy Moth, reliable.

Birth of the Gipsy Major

For all of this the new engine still had one drawback: its cylinders were still built on top of the crankshaft and therefore were sticking out of the top of the fuselage, right in the pilot's field of vision. Lowering the engine was impossible as the crankshaft was directly connected to the propeller and the propeller could not be placed too low lest it would plough into the ground on hard landings or bumpy fields. The solution came as several pilots boasted that they would be able to fly their Moth upside down for as long as they wanted if it were not for the carburettor and fuel tank now being inverted. Halford decided to test this by mounting a Gipsy engine upside down and then inverting its

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

so it was now right side up again. The design proved to run just as flawlessly as the regular Gipsy engine and soon the Gipsy I and II were replaced on the production lines by the Gipsy III inverted four-cylinder engine. The Moth with this new engine became the D.H.60 G-III; as the Gipsy III was quickly developed further into the Gipsy Major, the D.H.60 G-III was baptised the Moth Major. Building on the success of the D.H.60, de Havilland now started building other sports aircraft and trainers, all of which were powered by its own Gipsy engines. The company now produced Gipsy engines for other manufacturers as well and the Gipsy Major in particular became the engine of choice for scores of light aircraft designs, British as well as foreign. Most notably it was the engine of the famous World War II D.H.82A Tiger Moth trainer.

Variants

;Gipsy I :Original production version. 1,445 built.Lumsden 2003, p.71. De Havilland Gipsy II

;Gipsy II :Stroke increased to 5.5 in (140 mm). Power 120 hp (90 kW) at 2,300 rpm. 309 builtLumsden 2003, p.71. ;Gipsy III :As Gipsy II, inverted. 611 built.Lumsden 2003, p.71. ;Gipsy IV :A smaller inverted four-cylinder in-line engine, derived from the Gipsy III, intended for light sporting aircraft. Forerunner of Gipsy Minor. Power 82 hp (61 kW). ; Gipsy Major :Further development of the Gipsy III. Originally 130 hp (92 kW) later 141 and 145 hp (105, 110 kW) ; Gipsy Minor :Further development of the Gipsy IV. Power 90 hp (67 kW). ;Gipsy R :Racing engine for

de Havilland DH.71 Tiger Moth The de Havilland DH.71 Tiger Moth was a British single-seat monoplane, designed to research high-speed flight and to test replacement engines for the Cirrus. Only two were built. Design and development It was a low-wing monoplane based on th ...

. 135 hp (100 kW) at 2,850 rpm. ;Wright-Gipsy L-320 :Licence production in the United States of the Gipsy I

Applications

Application list from Lumsden. Gipsy Minor and Major not included.

Gipsy I

Avro Avian The Avro Avian was a series of British light aircraft designed and built by Avro in the 1920s and 1930s. While the various versions of the Avian were sound aircraft, they were comprehensively outsold by the de Havilland Moth and its descendants ...

Bartel BM-4 The Bartel BM.4 was a Polish biplane primary trainer aircraft used from 1929 to 1939 by the Polish Air Force and Polish civilian aviation, manufactured in the Samolot factory in Poznań. It was the first plane of Polish design put into productio ...

Blackburn Bluebird IV The Blackburn Bluebird IV was a single-engine biplane light trainer/tourer biplane with side-by-side seating designed by the British aviation manufacturer Blackburn Aircraft. It was an all-metal development of the wooden Blackburn Bluebird I, ...

Breda Ba.15 The Breda Ba.15 was a two-seat light aircraft produced in Italy in 1928. Design and development It was a high-wing braced monoplane of conventional design that seated the pilot and passenger in tandem within a fully enclosed cabin. Ba.15s were f ...

* de Havilland DH.60G Gipsy Moth * de Havilland DH.60T Gipsy Moth Trainer * de Havilland D.H.71 Tiger Moth racer *

PZL.5 The PZL-5 was a Polish two-seat touring and sports aircraft of 1930 constructed and produced by the PZL. Design and development The aircraft was designed in 1929 by an amateur designer Władysław Kozłowski. It was a wooden biplane, similar t ...

Simmonds Spartan The Simmonds Spartan is a 1920s British two-seat biplane trainer/tourer aircraft built by Simmonds Aircraft Limited. History Not happy with the high cost of manufacturing light aircraft, O.E. Simmonds designed and built a wooden two-seat bipl ...

Southern Martlet The Southern Martlet was a single-engined, single-seat biplane sports aircraft. Six were built, including the rather different and unsuccessful Metal Martlet. Design and development The Southern Martlet was the first aircraft designed by tea ...

Spartan Arrow The Spartan Arrow is a British two-seat biplane aircraft of the early 1930s, built by Spartan Aircraft Limited. History Built as a successor to the company's first design the Simmonds Spartan, the Arrow was a two-seat biplane with a spruce a ...

* Westland Widgeon

Gipsy II

6229 Duchess of Hamilton York 180509 (14)

* Airspeed Ferry *

* de Havilland DH.60G Gipsy Moth * de Havilland DH.60T Gipsy Moth Trainer *

RWD-4 The RWD 4 was a Polish sports plane of 1930, constructed by the RWD team. Development The RWD 4 was constructed by the RWD team of Stanisław Rogalski, Stanisław Wigura and Jerzy Drzewiecki in Warsaw. It was based upon their earlier RWD 2 de ...

Saro Cutty Sark The Saro A17 Cutty Sark was a British amphibious aircraft from the period between World War I and 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 194 ...

Saro Windhover The Saro A.21 Windhover was a British amphibious aircraft from the period between World War I and World War II, constructed by Saunders-Roe, or ''Saro''. It was originally advertised as the A.19 Thermopylae after the famous clipper ship, bein ...

Short Mussel The Short S.7 Mussel was a single-engined two-seat monoplane built by Short Brothers to test the performance of their duralumin monocoque floats. Two were built. Development Having demonstrated the watertightness and corrosion resistance of du ...

Spartan Three Seater The Spartan Three Seater was a British three-seat biplane touring and pleasure-flying aircraft built by Spartan Aircraft Limited. History Built as a three-seat version of the Simmonds Spartan The Simmonds Spartan is a 1920s British tw ...

Gipsy III

Gipsy IV

de Havilland Swallow Moth The de Havilland DH.81 Swallow Moth was aimed at the low-cost sporting aircraft market during the Great Depression. It was a single-engined two-seat low-wing monoplane; only one was built. Development The DH. 81 Swallow Moth was a low-wing c ...

Gipsy R

* de Havilland DH.71 Tiger Moth racer

Survivors

As of October 2010 approximately 17 Gipsy-powered

s remain on the British register. Not all are currently airworthy.

Engines on display

Preserved de Havilland Gipsy engines are on public display at the: *

de Havilland Aircraft Heritage Centre The de Havilland Aircraft Museum, formerly the de Havilland Aircraft Heritage Centre, is a volunteer-run aviation museum in London Colney, Hertfordshire, England. The collection is built around the definitive prototype and restoration shops fo ...

Royal Air Force Museum Cosford The Royal Air Force Museum Cosford, located in Cosford in Shropshire, is a free (currently, 2022) museum dedicated to the history of aviation and the Royal Air Force in particular. The museum is part of the Royal Air Force Museum, a non-departme ...

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 a ...

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 ...

Specifications (Gipsy I)

References

Notes

Bibliography

* Bransom, Alan. ''The Tiger Moth Story, Fourth Edition''. Shrewsbury, UK: Airlife Publishing Ltd., 1991. . * Lumsden, Alec. ''British Piston Engines and their Aircraft''. Marlborough, Wiltshire: Airlife Publishing, 2003. .

External links

de Havilland Gipsy at the Royal Air Force Museum
{{DHaeroengines

Gipsy The Romani (also spelled Romany or Rromani , ), colloquially known as the Roma, are an Indo-Aryan ethnic group, traditionally nomadic itinerants. They live in Europe and Anatolia, and have diaspora populations located worldwide, with sign ...

1920s aircraft piston engines