Siddeley-Deasy was bought out by Armstrong Whitworth Development Company of Newcastle 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 with Vickers to form Vickers-Armstrongs. At this point, J. D. Siddeley brought Armstrong Siddeley and Armstrong Whitworth Aircraft into his control. In 1928, Armstrong Siddeley Holdings bought Avro from Crossley Motors. Also that year Siddeley partnered with Walter Gordon Wilson, inventor of the pre-selector gearbox, to create Improved Gears Ltd, which later became Self-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 by aviation pioneer Tommy Sopwith, owner of Hawker Aircraft, to form – along with the Gloster 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 the Siddeley family and the Middleton-Joy family who were manufactures of Filtrate Oil and had enjoyed considerable success in car-racing rallies. Armstrong Siddeley was merged with the aircraft engine business of Bristol Aeroplane Company (Bristol Aero Engines) to form Bristol 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 and Rolls-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 become British Aerospace (BAe) which with further mergers is now BAE Systems. Products Motor cars The first car produced from the union was a fairly massive machine, a 5-litre . A smaller 18 hp