| Industry | Motor cars Aircraft engines |
|---|---|
| Founded | 1919 |
| Defunct | 1960 |
| Fate | Merged withHawker Aircraft (1935) becameHawker Siddeley Merged withBristol Aero Engines (1960) |
| Successor | Armstrong Siddeley Owners Club Ltd |
| Headquarters | Coventry, England |
Key people | John Davenport Siddeley |
| Parent | Armstrong Whitworth (1919–27) |
| Subsidiaries | Armstrong Whitworth Aircraft (1927–35) |
Armstrong Siddeley was a British engineering group that operated during the first half of the 20th century. It was formed in 1919 and is best known for the production ofluxury vehicles andaircraft engines.
The company was created following the purchase byArmstrong Whitworth ofSiddeley-Deasy, a manufacturer of luxury motor cars that were marketed to the top echelon of society. After the merge of companies, this focus on quality continued throughout in the production of cars, aircraft engines,gearboxes for tanks and buses, rocket and torpedo motors, and the development of railcars. Company mergers and takeovers withHawker Aviation andBristol Aero Engines saw the continuation of the car production which ceased in August 1960.
The company was absorbed into theRolls-Royce conglomerate which was interested in the aircraft and aircraft engine business. Eventually, the remaining spares and all motor car interests were sold to the Armstrong Siddeley Owners Club Ltd,[1] which now owns the patents, designs, copyrights and trademarks, including the name Armstrong Siddeley.
Considered "an elegant car appropriate forroyal use", the "Armstrong Siddeley Saloon" was used by thePrince of Wales (later King Edward VIII) during his 1930 tour ofUganda.[2]

The Siddeley Autocar Company,[3] ofCoventry, was founded byJohn Davenport Siddeley (1866–1953) in 1902. Its products, made for him by aVickers subsidiary, were heavily based onPeugeots using many Peugeot parts and fitted with English-built bodies. J. D. Siddeley was appointed London sales manager of Vickers Limited's subsidiaryWolseley in early 1905[4] at the same time as Wolseley purchased the goodwill and patent rights of his Siddeley car.[note 1] A few months laterHerbert Austin left to form his own business and Siddeley was appointed general manager.[5]
Without the consent of the Vickers brothers Siddeley added his own name to the Wolseley nameplate but it was dropped on his departure.
In 1909, J. D. Siddeley resigned from Wolseley and in 1910, he took on management of The Deasy Motor Car Manufacturing Company, Limited. The shareholders were so pleased with his success in that post that on 7 November 1912 they unanimously agreed to change the company's name to The Siddeley-Deasy Motor Car Company Limited.[6][7] Siddeley's name had been added to the product's radiator earlier in 1912.[8] His cars began to use the slogan "As silent as the Sphinx", sporting aSphinx as a bonnet mascot.[9]

In April 1919, Siddeley-Deasy was bought out byArmstrong Whitworth Development Company ofNewcastle upon Tyne and in May 1919 became Armstrong Siddeley Motors Ltd, a subsidiary with J. D. Siddeley as managing director. In 1927, Armstrong Whitworth merged its heavy engineering interests withVickers to formVickers-Armstrongs. At this point, J. D. Siddeley brought Armstrong Siddeley andArmstrong Whitworth Aircraft into his control. In 1928, Armstrong Siddeley Holdings boughtAvro fromCrossley Motors. Also that year Siddeley partnered withWalter Gordon Wilson, inventor of thepre-selector gearbox, to create Improved Gears Ltd, which later becameSelf-Changing Gears – the gearbox that should be credited with enabling the marketing tagline "Cars for the daughters of gentlemen".
Armstrong Siddeley manufactured luxury cars, aircraft engines, and later, aircraft. In 1935, J. D. Siddeley's interests were purchased for £2 million[10] by aviation pioneerTommy Sopwith, owner ofHawker Aircraft, to form – along with theGloster Aircraft Company and Air Training Services –Hawker Siddeley, a famous name in British aircraft production. Armstrong Whitworth Aircraft and Armstrong Siddeley Motors became subsidiaries of Hawker Siddeley, with Sopwith himself becoming the new chairman of Armstrong Siddeley Motors. At this time, there remained an "unbroken business association" between theSiddeley family and theMiddleton-Joy family who were manufactures ofFiltrate Oil and had enjoyed considerable success incar-racing rallies.[11][12]
Armstrong Siddeley was merged with the aircraft engine business ofBristol Aeroplane Company (Bristol Aero Engines) to formBristol Siddeley as part of an ongoing rationalisation under government influence of the British aircraft and aircraft engine manufacturers. Armstrong Siddeley produced their last cars in 1960. Bristol Siddeley andRolls-Royce merged in 1966, the latter subsuming the former which remained for a while as an aircraft engine division within Rolls-Royce.
In June 1972, Rolls-Royce (1972) Ltd sold all the stock of spares plus all patents, specifications, drawings, catalogues and the name of Armstrong Siddeley Motors Ltd to the Armstrong Siddeley Owners Club Ltd. This meant that "Armstrong Siddeley" and "A-S Sphinx Logo" are trademarks and copyright of the Armstrong Siddeley Owners Club Ltd.
The "Siddeley" name survived a while longer in aviation, through Hawker Siddeley Aviation and Hawker Siddeley Dynamics. In 1977 they joined with others to becomeBritish Aerospace (BAe) which with further mergers is nowBAE Systems.

The first car produced from the union was a fairly massive machine, a 5-litre30 hp. A smaller 18 hp appeared in 1922 and a 2-litre 14 hp was introduced in 1923. 1928 saw the company's first 15 hp six; 1929 saw the introduction of a 12 hp vehicle. This was a pioneering year for the marque, during which it first offered theWilsonpreselector gearbox as an optional extra; it became standard issue on all cars from 1933. In 1930 the company marketed four models, of 12, 15, 20, and 30 hp, the last costing £1450.
The company's rather staid image was endorsed during the 1930s by the introduction of a range of six-cylinder cars withohv engines, though afour-cylinder 12 hp was kept in production until 1936.
In 1932 - or thereabouts, a line of special, rather more sporty designs was started which resulted in the Rally Tourer series. The aim was to help shake off the somewhat pedestrian image of what was in fact a rather advanced product. Of the 16 rally tourers built, many were used by the owners or senior directors, and were entered into various rallies, achieving some good results and making for good publicity. Only one of those 16 special cars is now known to exist: a 1933, Long-15 Rally Tourer which, according to the records, shared the same body as the 20 hp version (which had a slightly longer bonnet).
In 1933, the 5-litre six-cylinder Siddeley Special was announced, featuring aHiduminium aluminium alloy engine; this model cost £950. Car production continued at a reduced rate throughout 1940, and a few were assembled in 1941.
The week thatWorld War II ended in Europe, Armstrong Siddeley introduced its first post-war models; these were theLancaster four-doorsaloon and the Hurricanedropheadcoupe. The names of these models echoed the names ofaircraft produced by theHawker Siddeley Group (the name adopted by the company in 1935) during the war. These cars all used a 2-litre six-cylinder (16 hp) engines, increased to 2.3-litre (18 hp) engines in 1949. From 1949 to 1952 two commercial variants of the18 hp Whitleys were produced, primarily for export. The Utility Coupé was a conventionalcoupe utility style vehicle, while the Station Coupé was effectively a dual cab vehicle, although it still retained only two doors. However, it did have two rows of seating to accommodate up to four adults and the doors were larger to allow better access to the rear. From 1953 the company produced the Sapphire, with a 3.4-litre six-cylinder engine.
In 1956, the model range was expanded with the addition of the 234 (a 2.3-litre four-cylinder) and the 236 (with the older 2.3-litre six-cylinder engine). The Sapphire 346 sported a bonnet mascot in the shape of a sphinx with namesakeArmstrong Siddeley Sapphire jet engines attached. The 234 and 236 Sapphires might have looked to some of marque's loyal customers like a radical departure from the traditional Armstrong Siddeley appearance. However, in truth, they were simply too conservative in a period of rapidly developing automotive design. If the "baby Sapphire" heralded the beginning of the end for Armstrong Siddeley, it was because Jaguar had launched the unitary-construction 2.4 saloon in 1955, which was quicker, significantly cheaper, and much better-looking than the 234 and 236.
The last new model produced by Armstrong Siddeley was 1958's Star Sapphire, with a 4-litre engine, andautomatic transmission. The Armstrong Siddeley was a casualty of the 1960 merger with Bristol; the last car left the Coventry factory in 1960.
Cars produced by Armstrong Siddeley had designations that came from thetax horsepower rating of their engines.



| Model name | Type | Engine | From | To | No. produced |
|---|---|---|---|---|---|
| Thirty[14][15] | Various | 4960 cc | 1919 | 1931 | 2770 |
| Eighteen[16][15] | Various | 2380 cc | 1921 | 1925 | 2500 (combined) |
| 18/50 or 18 Mk.II[17] | Various | 2872 cc | 1925 | 1926 | |
| Four-Fourteen[18][19][20][21][22] | Various | 1852 cc | 1923 | 1929 | 13,365 |
| Twenty[23] | Short and Long chassis | 2872 cc | 1926 | 1936 | 8847 |
| Fifteen[23] | Tourer, saloon | 1900 cc | 1927 | 1929 | 7203 inc 15/6 |
| Twelve[23] | Tourer, saloon, sports | 1236 (1434 cc from 1931) | 1929 | 1937 | 12,500 |
| 15/6 | Tourer, saloon, sports | 1900 cc (2169 cc from 1933) | 1928 | 1934 | 7206 (incl. Fifteen) |
| Siddeley Special | Tourer, saloon, limousine | 4960 cc | 1933 | 1937 | 253 |
| Short 17 | Coupe, saloon, sports saloon | 2394 cc | 1935 | 1938 | 4260 (combined) |
| Long 17 | Saloon, tourer, Atalanta sports saloon, Limousine, landaulette | 2394 cc | 1935 | 1939 | |
| 12 Plus & 14 | Saloon, tourer | 1666 cc | 1936 | 1939 | 3750 |
| 20/25 | Saloon, tourer, Atlanta sports saloon Limousine, landaulette | 3670 cc | 1936 | 1940 | 884 |
| 16 | Saloon, Sports saloon | 1991 cc | 1938 | 1941 | 950 |
| Lancaster 16 | 4-door saloon | 1991 cc | 1945 | 1952 | 3597 (combined) |
| Lancaster 18 | 4-door saloon | 2309 cc | 1945 | 1952 | |
| Hurricane 16 | Drophead coupé | 1991 cc | 1945 | 1953 | 2606 (combined) |
| Hurricane 18 | Drophead coupé | 2309 cc | 1945 | 1953 | |
| Typhoon | 2-door fixed-headcoupé | 1991 cc | 1946 | 1949 | 1701 |
| Tempest | 4-door fixed-headcoupé | 1991 cc | 1946 | 1949 | 6 |
| Whitley 18 | Various | 2309 cc | 1949 | 1953 | 2624 |
| Sapphire 346 | 4-door saloon & Limousine | 3435 cc | 1952 | 1958 | 7697 |
| Sapphire 234 | 4-door saloon | 2290 cc | 1955 | 1958 | 803 |
| Sapphire 236 | 4-door saloon | 2309 cc | 1955 | 1957 | 603 |
| Star Sapphire | Saloon & Limousine | 3990 cc | 1958 | 1960 | 980 |
| Star Sapphire Mk II | Saloon & Limousine | 3990 cc | 1960 | 1960 | 1 |
A feature of many of their later cars was the option of an electrically controlled pre-selector gearbox.
Like many British cars of this era, there are active owners' clubs supporting their continued use in several countries, e.g. the UK, Australia, New Zealand, the Netherlands and Germany. Armstrong Siddeley Owners Club Ltd has members worldwide and many members of the ASCC in Australia are resident overseas.
In the United Kingdom, ASOC publishes a monthly members magazineSphinx. In Australia, the Armstrong Siddeley Car Club publishesSouthern Sphinx six times a year. In the Netherlands, ASOC Dutch also publishes six times a year, and in New Zealand, Armstrong Siddeley Car Club in New Zealand Inc. publishSphinx-NZ monthly.[24]

Throughout the 1920s and 1930s, Armstrong Siddeley produced a range of low- and mid-power aircraftradial engines, all named afterbig cats. They also produced a tiny 2-cylinder engine called theOunce, another name for thesnow leopard, for ultralight aircraft.
The company started work on their firstgas turbine engine in 1939, following the design pioneered at theRoyal Aircraft Establishment byAlan Arnold Griffith. Known as the "ASX" for "Armstrong Siddeley eXperimental", the original pure-turbojet design was later adapted to drive a propeller, resulting in the "ASP". From then on, AS turbine engines were named aftersnakes. TheMamba andDouble Mamba wereturboprop engines, the latter being a complex piece of engineering with two side-by-side Mambas driving through a common gearbox, and could be found on theFairey Gannet. ThePython turboprop powered theWestland Wyvern strike aircraft. Further development of the Mamba removed thereduction gearbox to give theAdderturbojet.
Another pioneer in the production of the RAE engine design wasMetrovick, who started with a design known as theMetrovick F.2. This engine never entered production, and Metrovick turned to a larger design, the Beryl, and then to an even larger design, theSapphire. Armstrong Siddeley later took over the Sapphire design, and it went on to be one of the most successful 2nd generation jet engines, competing with the better-knownRolls-Royce Avon.
The company went on to develop an engine – originally for unmannedJindiviktarget drones – called theViper. This product was further developed by Bristol Siddeley and, later, Rolls-Royce and was sold in great numbers over many years. A range ofrocket motors were also produced, including theSnarler andStentor. The rocket development complemented that of Bristol, and Bristol Siddeley would become the leading British manufacturer of rocket engines for missiles.
| year | type | |
|---|---|---|
| Armstrong Siddeley Cheetah | 1935 | 7-cyl radial |
| Armstrong Siddeley Civet | 1928 | 7-cylinder radial |
| Armstrong Siddeley Cougar | 1945 | 9-cylinder radial not-produced |
| Armstrong Siddeley Deerhound | 1935 | 21-cylinder 3-row in-line radial engine. Not produced |
| Armstrong Siddeley Genet | 1926 | 5-cylinder radial |
| Armstrong Siddeley Genet Major | 1928 | radial |
| Armstrong Siddeley Hyena | 1933 | experimental 15-cylinder 3-row inline radial |
| Armstrong Siddeley Jaguar | 1923 | 14-cylinder 2-row radial |
| Armstrong Siddeley Leopard | 1927 | 14-cylinder, 2-row radial |
| Armstrong Siddeley Lynx | 1920 | radial |
| Armstrong Siddeley Mongoose | 1926 | 5-cyl radial |
| Armstrong Siddeley Ounce | 1920 | 2-cylinder opposed |
| Armstrong Siddeley Panther | 1929 | 14-cylinder 2-row radial |
| Armstrong Siddeley Puma[25] | 1917-1918 | 6 cylinder water-cooled inline aircraft piston engine |
| Armstrong Siddeley Serval | 1928 | 10-cylinder 2-row radial |
| Armstrong Siddeley Tiger | 1932 | 14-cylinder 2-row radial supercharged |
| Armstrong Siddeley ASX | 1945 | axial flow turbojet |
| Armstrong Siddeley Python | 1945 | turboprop, also known as ASP |
| Armstrong Siddeley Double Mamba | 1949 | Two Mamba linked by gearbox |
| Armstrong Siddeley Mamba | 1946 | turboprop |
| Armstrong Siddeley Sapphire | 1948 | turbojet |
| Armstrong Siddeley Adder | 1948 | turbojet |
| Armstrong Siddeley Viper | 1951 | turbojet |
| Armstrong Siddeley Snarler | 1950 | rocket |
In 1946 Armstrong Siddeley produced their firstdiesel engines. They were medium-speed engines for industrial and agricultural use. Initially there was a single-cylinder engine producing 5 bhp (3.7 kW) at 900 rpm and a twin-cylinder version. Each cylinder had a capacity of 988 cm3 (60.2 cubic inches). The power output and speed was progressively increased. By the end of 1954 the single-cylinder engine was rated at 11 bhp (8.2 kW) at 1800 rpm and the twin-cylinder engine 22 bhp (16 kW) at the same speed. In 1955 the range was extended with the introduction of a 3-cylinder engine rated at 33 bhp (25 kW).[26]
The engines were built at Armstrong Siddeley's factory at Walnut Street inLeicester until that factory closed in August 1957.[27] Production was transferred to the factory of Armstrong Siddeley (Brockworth) Ltd in Gloucestershire and in 1958 to the factory ofPetters Limited at Staines, Middlesex. The engines built by Petters were designated AS1, AS2 and AS3 to distinguish them from that company's other products. Production ended in 1962 when Pettersintroduced a replacement range of lightweight small high-speed air-cooled diesel engines.[28]
In April 1958 the company obtained a licence to build theMaybach MD series high-speed diesel engines.[29] Several hundred were built by Bristol Siddeley Engines Ltd after that company took over Armstrong Siddeley's manufacturing activities in 1959.
Citations
This is a photograph of the long twenty Armstrong-Siddeley Saloon of the same style used by HRH in Uganda. It was an elegant car thought appropriate for royal use.
J.A. Middleton-Joy, of Leeds, whose success in winning The Yorkshire Post Cup was announced to-day, drove a fifteen-horsepower short wheelbase Armstrong-Siddeley, which was not fitted with any special device, although has the standard Armstrong-preselect,... [Also]-Yorkshire Post and Leeds Intelligencer Yorkshire, England - 7 Mar 1932, In 1903 Mr. J.D. Siddeley asked Mr. Joy to produce an oil specially suitable for the Siddeley-Deasy cars he was then producing, and from then onwards there has been an unbroken business association between the Siddeley and [Middleton] Joy families.
Filtrate Oils
Bibliography