Hawker Siddeley Group PLC was initially formed as the Hawker Siddeley Aircraft Company on 11th July 1935. The new company was established to acquire all of the shares of the Armstrong Siddeley Development Company and 50% of the shares of the Hawker Aircraft Company. This merged the two largest British aircraft manufacturers and included the subsidiaries of the two companies involved. These consisted of Armstrong Siddeley Motors, Sir W.G. Armstrong Whitworth Aircraft Ltd and A.V. Roe and Co, which were part of the Armstrong Siddeley Development Company, and the Gloster Aircraft Company, which was part of Hawker, all of which continued to produce aircraft under their own names. During the Second World War Hawker Siddeley was one of the most important aircraft manufacturers in Britain. During the course of the conflict it produced several important designs including the Hawker Hurricane and Avro Lancaster as well as working on Britain’s first jet aircraft, the Gloster E.28/39, and the first British jet fighter, the Gloster Meteor. In 1945 the company also purchased Victory Aircraft from the Canadian government and transferred to its subsidiary Avro. This then became A.V. Roe Canada but was most often know as Avro Canada. On 22nd June 1948 the company underwent a restricting when it was transformed from a private to a public limited company and underwent a name change. As such it went from being Hawker Siddeley Aircraft Company Limited to Hawker Siddeley Group Limited. In 1957 the Hawker Siddeley Group purchased the Brush Group, which included Brush Electrical Machines and Brush Traction. At the time it also acquired Mirrlees, Bickerton and Day. It also formed Hawker Siddeley John Brown Nuclear Construction as a joint venture to produce nuclear power equipment for marine propulsion, electrical generation and other industrial applications. In 1958 it formed another join company this time with Beyer Peacock, under the name Beyer Peacock (Hymek) Ltd, in order to manufacture diesel hydraulic locomotives. 1959 saw a further joint company, Primapax, which made, hired and sold vending machines. During the late 1950s the British government decided that the number of aircraft manufacturers should be decreased as the number of contracts being offered was being reduced. As a result of this Hawker Siddeley merged all of its aviation interests, Hawker, Avro, Gloster, Armstrong Whitworth and Armstrong Siddeley, into a single division, Hawker Siddeley Aviation during October 1958. In 1959 it also merged its aircraft engine business, Armstrong Siddeley, with Bristol Aero Engines to form Bristol Siddeley Engines. The group also acquired Folland Aircraft and in 1960 purchased both the de Havilland Aircraft Company and the Blackburn Group. By 1961 the Hawker Siddeley Group was made up of 3 major operational groups, Hawker Siddeley Aviation, Hawker Siddeley Industries and A.V. Roe Canada. Avro Canada would be dissolved in 1962 due to the cancellation of the Avro Arrow aircraft with its remaining assets being transferred to Hawker Siddeley Canada. The new company focused on the manufacture of railway vehicles, subway cars and trams. In 1963 the group underwent a further restructuring as the names of its constituent companies were dropped in favour of a single Hawker Siddeley branding. As a result, the company’s products were rebranded with a HS number in place of their previous number. During 1968 the group expanded further by acquiring Crompton Parkinson, which was later combined with Brook Motors, when they acquired this company in 1970, to form Brook Crompton. On 29th April 1977 the Hawker Siddeley Group underwent a major change when, as a result of the Aircraft and Shipbuilding Industries Act, its Aviation and Dynamics groups were nationalised and merged with the British Aircraft Corporation and Scottish Aviation to form British Aerospace. Despite this loss of its aviation interests, they only accounted for 25% of the group’s business and as such it was able reorganise its remaining interests in a holding company, Hawker Siddeley Group PLC. The decision was taken to focus this group on railway engineering, industrial electronics and signalling equipment. During the 1980s the Hawker Siddeley Group continued to expand, acquiring Carlton Industries between 1981 and 1984, and GEC Small Machines Company and GEC Alsthom Electromotes in 1989. This success made the group a target for a hostile takeover by the BTR conglomerate and in November 1991 they acquired it for £1.5 billion. The Hawker Siddeley name continued to be used in the group’s switchgear division which was later sold to FKI and later Melrose PLC.

A V Roe and Co Ltd, more commonly known as Avro, was an aircraft manufacturer based in Manchester. One of the first manufacturers of aircraft, the company operated from 1910 until 1963. Avro was founded by brothers Alliott and Humphrey Verdon Roe and was based originally in the basement of the Everards Elastic Webbing Company's factory at Brownsfield Mill in Ancoats, Manchester. Avro also rented a shed at Brooklands airfield, where the finished aircraft were sold. Alliott Verson Roe was the aircraft designer, having already constructed a successful aircraft, the Roe I Triplane, in 1909. The Roe I was the first aircraft completely built from British components. Previous aircraft designs had used parts imported from overseas. Humphrey Verdon Roe was the managing director of the company, bringing funding for the new enterprise from the family webbing company that he also ran. In 1911 Roy Chadwick joined the company as Alliott’s personal assistant, working as a draughtsman. Chadwick became the firm's Chief Designer in 1918. The Avro 500, or Avro E, was the company's first mass produced aircraft. It took its first flight in March 1912. Eighteen of these were built, with most of them entering service with the Royal Flying Corps. In the same year, Avro prototyped the Avro F and Avro G, which were the world's first aircraft with fully enclosed crew accommodation, but neither went into production. September 1913 saw the first flight of the Avro 504. This was a development of the Avro 500 and was purchased by the War Office. As a result, it would see front line service during the early years of the First World War, but was later used primarily for training pilots. The Avro 504 was manufactured for a period of 20 years, with 8,340 being produced in total. The success of the Avro 504 led the company to move to a factory in Miles Platting, Manchester, followed in 1914 by an extension to the company's new works at Newton Heath, which was completed in 1919. Following the end of the First World War the lack of new orders caused severe financial problems for Avro and in August 1920 68.5% of the company’s shares were acquired by Crossley Motors, who needed additional factory space to build automobile bodies. Avro continued to operate, building aircraft at the Newton Heath works, and testing them at Alexandra Park Aerodrome in South Manchester until 1924, when flight testing moved to Woodford Aerodrome in Cheshire. In 1928, Crossley Motors sold their stake in Avro to Armstrong Siddeley in order to pay off losses they had incurred on other projects. Avro became part of the Armstrong Siddeley Development Company, prompting Alliott Verdon Roe's resignation from the company. Chief Designer Roy Chadwick remained at Avro, overseeing the production of training aircraft. Chadwick designed the Avro Tutor in 1930, followed by the twin engine Avro 652, which was later developed into the multirole Avro Anson. The Tutor was bought in large quantities by the RAF. In 1935, Avro became a subsidiary of Hawker Siddeley. As tensions in Europe increased, resulting in the outbreak of the Second World War, Avro returned to the production of military aircraft, producing the Avro Manchester, Lancaster and Lincoln bombers. The twin engine Manchester was unsuccessful, partly due to its Vulture engines. Replacing the Vultures with four Rolls-Royce Merlin engines resulted in the more successful Lancaster. 7,377 of these were produced and saw active service during the war. In 1944, the Lancaster was further developed into the Lincoln, the last piston engine bomber in Royal Air Force service. In order to meet rising demand Avro opened a new factory at Greengate, Chadderton, in 1938, where almost half of all Avro Lancasters were produced, with final assembly at Woodford Aerodrome. The following year, Avro also established an experimental department at RAF Ringway, now known as Manchester Airport, and a shadow factory at Yeadon Aerodrome, now Leeds-Bradford Airport. The Yeadon factory produced 5,500 aircraft including Ansons, Lancasters, Yorks and Lincolns. Towards the end of the Second World War, Avro put into production a number of civil airliners, in order to make up for a drop in military orders. One of these designs was the Lancastrian, which was a conversion of the Lancaster bomber. The second was the Avro York, which was also based on the Lancaster but used a different fuselage. Production of this would be limited until 1944 due to the focus on military aircraft. The final design that the company produced was the Tudor. This used many components from the Lincoln but suffered from the fact that it wasn’t sufficiently advanced when compared to existing designs and as a result it did not achieve many orders. Despite this both the York and Tudor were used in the Berlin Airlift. On 23rd August 1947 Roy Chadwick was killed in a crash involving a prototype Tudor 2 that was undergoing testing. Despite this his impact on the company continued, as he had already begun design work on a number of aircraft that Avro went on to produce. In 1948 Avro produced the Tudor 8 which was powered by four Nene jet engines. This design retained the tail wheel undercarriage, which placed the engine exhausts close to the ground. As a result, the company replaced this with a tricycle undercarriage for the Tudor 9. The design became known as the Avro Ashton, which first flew in 1950. Although this was one of the first jet transport aircraft it was primarily used for research and it was not intended to enter service. On 30th August 1952 the Avro 698 made its first flight. This was a four engine jet bomber that had been developed to replace existing piston engine designs. Further development of the design resulted in the Avro 707 and the Avro 710. The 710 was not put into full production as it was considered too time consuming to develop. The 698 entered service in 1956 under the name Vulcan, with an improved B.2 version introduced in 1960. The Avro Vulcan was retired in 1984 after having only being using in combat once, during the 1982 Falklands War. During the late 1950s the company developed the 748 turbo-prop airliner. This successful design was sold around the world and was later developed into the Ashton transport by Hawker Siddeley. The same period also saw the company’s weapons research division begin development of the Blue Steel nuclear missile. During 1963, parent company Hawker Siddeley restructured its aviation subsidiaries. Each subsidiary had operated under its own brand name, but from July 1963 all subsidiaries were merged into Hawker Siddeley's Aviation Division, which was operated as a single brand. The missile division of the company would become part of the Dynamics Division. Avro as a company ceased to exist, but the Avro was later reused by British Aerospace for their 146 regional airliner, known as the Avro RJ.