Pobjoy Airmotors and Aircraft was a

British British may refer to: Peoples, culture, and language * British people, nationals or natives of the United Kingdom, British Overseas Territories, and Crown Dependencies. ** Britishness, the British identity and common culture * British English, ...

manufacturer of small

aircraft 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 ...

s. The company was purchased by

Short Brothers Short Brothers plc, usually referred to as Shorts or Short, is an aerospace company based in Belfast, Northern Ireland. Shorts was founded in 1908 in London, and was the first company in the world to make production aeroplanes. It was particu ...

shortly before the start of

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 ...

, production continuing until the end of the war.

History

Douglas Rudolf Pobjoy started in the engine business working with

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 weal ...

Cosmos Engineering Cosmos Engineering was a company that manufactured aero-engines in a factory in Fishponds, Bristol during World War I. Sir Roy Fedden, the company's principal designer, developed the 14-cylinder radial Mercury engine during this period. The com ...

just after the end of

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 ...

. Cosmos went bankrupt shortly after the war, and its assets were picked up 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 ...

, where Fedden would go on to produce a line of extremely successful engines. Pobjoy also spent time in the

RAF The Royal Air Force (RAF) is the United Kingdom's air and space force. It was formed towards the end of the First World War on 1 April 1918, becoming the first independent air force in the world, by regrouping the Royal Flying Corps (RFC) and ...

as an education officer. Here he met Flt. Lt.

Nicholas Comper Nicholas Comper (29 April 1897 – 17 June 1939) was an English aviator and aircraft designer, whose most notable success was the 1930s Comper Swift monoplane racer. Early life Nicholas Comper was born in Lambeth, London, England, the son of c ...

who went on to design the

Comper Swift The Comper C.L.A.7 Swift is a British 1930s single-seat sporting aircraft produced by Comper Aircraft Company Ltd of Hooton Park, Cheshire. Design and development In March 1929 Flight Lieutenant Nicholas Comper left the Royal Air Force and form ...

, that would later fly from London to Australia in 9 days 2 hours. Pobjoy partnered with

Parnall Parnall was a British aircraft manufacturer that evolved from a wood-working company before the First World War to a significant designer of military and civil aircraft into the 1940s. It was based in the west of England and was originally known a ...

to develop an engine for the Swift. Although they felt that a cast-block inline engine like the ones being produced by

Cirrus Cirrus may refer to: Science *Cirrus (biology), any of various thin, thread-like structures on the body of an animal *Cirrus (botany), a tendril *Infrared cirrus, in astronomy, filamentary structures seen in infrared light *Cirrus cloud, a type ...

and

de Havilland 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 ...

would always be less expensive, they nevertheless selected the

radial Radial is a geometric term of location which may refer to: Mathematics and Direction * Vector (geometric), a line * Radius, adjective form of * Radial distance, a directional coordinate in a polar coordinate system * Radial set * A bearing f ...

layout for their design, feeling that the cost would be more than offset by the lighter weight and higher performance his designs would offer. Douglas Pobjoy later took over the design, and started a company of his own to produce it at

Hooton Park Royal Air Force Hooton Park or more simply RAF Hooton Park, on the Wirral Peninsula, Cheshire, is a former Royal Air Force station originally built for the Royal Flying Corps in 1917 as a training aerodrome for pilots in the First World War. ...

in the Wirral. The Parnall/Pobjoy design, the 7-cylinder 67 hp Pobjoy P, received its 50-hour type rating in 1928. This was followed in 1929 by the 75/80 hp

Pobjoy R The Pobjoy R is a British seven-cylinder air-cooled radial aircraft engine designed and built by Pobjoy Airmotors. Introduced in 1926, it was a popular engine for ultralight and small aircraft in the 1930s. A notable feature of the Pobjoy R was ...

, that became very successful, notably on the

General Aircraft Monospar The General Aircraft Monospar was a 1930s British family of touring and utility aircraft built by General Aircraft Ltd (GAL). Design and development In 1929, the Monospar Company Ltd was formed to pursue new techniques of designing cantileve ...

. Later designs included the 85/90 hp Pobjoy Cataract, replacing the Pobjoy R, and the 130 hp

Pobjoy Niagara The Pobjoy Niagara is a British seven-cylinder, air-cooled, radial, aero-engine first produced in 1934. The design ran at higher speeds than conventional engines, and used reduction gearing to lower the speed of the propeller. This led to a noti ...

of 1934. The Niagara was used on a number of designs by Shorts designers, notably the

Short Scion Senior The Short S.22 Scion Senior was a 1930s United Kingdom, British four-engined nine-passenger floatplane built by Short Brothers. Design and development The Scion Senior was developed as an enlarged version of the Short Scion, Scion light transpo ...

and the original half-scale prototype for the

Short Stirling The Short Stirling was a British four-engined heavy bomber of the Second World War. It has the distinction of being the first four-engined bomber to be introduced into service with the Royal Air Force (RAF). The Stirling was designed during t ...

, the S.31. The Niagara's compact size and excellent performance led to it being used on the General Aircraft GAL.38 and

Airspeed AS.39 The Airspeed AS.39 Fleet Shadower was a British long-range patrol aircraft design that did not go beyond the prototype stage. A similar aircraft, the General Aircraft Fleet Shadower, was also built to the extent of prototypes. While the concept o ...

extremely long-endurance slow-flying "Fleet Shadower" prototypes produced to

Air Ministry specification This is a partial list of the British Air Ministry (AM) specifications for aircraft. A specification stemmed from an Operational Requirement, abbreviated "OR", describing what the aircraft would be used for. This in turn led to the specification ...

S.23/27"Lumsden (2003) where they maximized airflow over the wings. In 1934, Pobjoy Airmotors moved its plant to

Rochester, Kent Rochester ( ) is a town in the unitary authority of Medway, in Kent, England. It is at the lowest bridging point of the River Medway, about from London. The town forms a conurbation with neighbouring towns Chatham, Rainham, Strood and Gillin ...

, to be closer to its largest customer, Shorts. The move, and the ongoing effects of the

Great Depression The Great Depression (19291939) was an economic shock that impacted most countries across the world. It was a period of economic depression that became evident after a major fall in stock prices in the United States. The economic contagio ...

, drove the company into financial difficulty, and it was eventually bought outright by Shorts. The company was made public in 1935. Douglas Pobjoy then moved on to designing de-icing equipment for high-altitude flights. During the Second World War, Pobjoy ran a section of

Rotol Airscrews Dowty Propellers is a British engineering company based in Brockworth, Gloucestershire that specialises in the manufacture, repair and overhaul of propellers and propeller components for customers around the world. It is owned by General Elect ...

of Gloucester, England, and was responsible for the design and development of an airborne generator, intended for use on the

Short Shetland The Short Shetland was a British high-speed, long-range, four-engined flying boat built by Short Brothers at Rochester, Kent for use in the Second World War. It was designed to meet an Air Ministry requirement (defined in Specification R.14/4 ...

flying boat. The unit consisted of a flat-six sleeve-valve air-cooled petrol engine driving the generator. This was installed inboard on the aircraft, and due to the incorrect closure of the cooling ducts the engine overheated and the resulting fire destroyed the prototype Shetland. It seems that the project was abandoned at this stage. After the war Pobjoy designed a new tractor. On 4 July 1948, he was returning from a sales trip to

Helsinki Helsinki ( or ; ; sv, Helsingfors, ) is the Capital city, capital, primate city, primate, and List of cities and towns in Finland, most populous city of Finland. Located on the shore of the Gulf of Finland, it is the seat of the region of U ...

when the

Scandinavian Airlines Scandinavian Airlines, more commonly known and styled as SAS, is the flag carrier of Denmark, Norway, and Sweden. ''SAS'' is an abbreviation of the company's full name, Scandinavian Airlines System or legally Scandinavian Airlines System Denmark ...

Douglas DC-6 The Douglas DC-6 is a piston-powered airliner and cargo aircraft built by the Douglas Aircraft Company from 1946 to 1958. Originally intended as a military transport near the end of World War II, it was reworked after the war to compete with th ...

in which he was flying was involved in the 1948 Northwood mid-air collision. All 38 passengers in both aircraft were killed.Lumsden (2003), p.178.

Aircraft

* Pobjoy Pirate

Engine designs

* Pobjoy P (1928) :7-cylinder radial, air-cooled, geared, 2,480 cc, 67 hp (50 kW) *

(1933) :7-cylinder radial, air-cooled, geared, 2,835 cc, 85 hp (63 kW) * Pobjoy Cataract I-III (1934-6) :7-cylinder radial, air-cooled, geared, 2,835 cc, three marks with take-off powers from 80-98 hp (60-73 kW) * Pobjoy Cascade (1934) :7-cylinder radial, air-cooled, direct drive version of Cataract I, 2,835 cc, take-off power 70 hp (52 kW) * Pobjoy Niagara I-IV (1936-7) :7-cylinder radial, air-cooled, geared, cowled, 2,835 cc, four marks with take-off powers from 84-98 hp (63-73 kW) *

Pobjoy Niagara V The Pobjoy Niagara is a British seven-cylinder, air-cooled, radial, aero-engine first produced in 1934. The design ran at higher speeds than conventional engines, and used reduction gearing to lower the speed of the propeller. This led to a noti ...

(1937) :7-cylinder radial, air-cooled, geared, cowled, 3,138 cc, take-off power 142 hp (106 kW)

Notes

References

* Jane's Fighting Aircraft of World War II. 1946 * Lumsden, Alec. 2003. British Piston Engines and their Aircraft. Airlife Publishing. . {{Pobjoy aeroengines Defunct aircraft engine manufacturers of the United Kingdom

History

Aircraft

Engine designs

See also

Notes

References