GEC Traction (GECT) was formed in 1972 as part of the GEC Power Engineering Group following earlier amalgamations of the traction divisions of the General Electric Company (GEC), the English Electric Company (EE) and Associated Electrical Industries (AEI). A wholly owned subsidiary company of GEC, the company had offices and works, located at Trafford Park in Manchester, at Strand Road in Preston, and at Attercliffe Common, Sheffield. The headquarters of GEC Traction was Trafford Park, Manchester (previously the headquarters of English Electric-AEI Traction) with design of rotating machines at Preston and Sheffield, and manufacturing activities for control equipment at Manchester and Preston. GEC Traction designed and manufactured a full range of traction machines and control equipment for electric vehicles, including electric locomotives and multiple unit trains for main-line and mass-transit railway systems (dc up to 3,000 volts, and ac up to 50,000 volts), diesel-electric locomotives and trains, mining and industrial locomotives, tramcars and trolleybuses. GEC Traction was the leading supplier of traction equipment in the UK and had a wide market around the world, particularly in South Africa, Australasia, Hong Kong, South Korea, South America and Pakistan. In 1979 the Industrial Locomotive Division of the former English Electric which was based at Vulcan Works, Newton-le-Willows was merged into GEC Traction, which later became a separate company, GEC Industrial Locomotives Ltd. During the late 1980s and 1990s the firm underwent major rationalisation, involving closure of several sites including Attercliffe Common in Sheffield in 1985 and the company’s headquarters at Trafford Park in Manchester in 1998. The company name GEC Traction endured until a merger with the French Alsthom group in 1989, which created GEC Alsthom Traction, which was still a branch of the main company GEC Alsthom.

GEC Transportation Projects Ltd., (GEC-TPL) was established in 1974 and was based at St Albans and Borehamwood, Hertfordshire. It specialised in the design, execution and management of major railway and mass transit electrification projects around the world. In 1981 GEC-TPL was transferred to Trafford Park in Manchester took over residual responsibility for vehicle design from GEC Traction, e.g. British Railways Class 91s and locomotive equipment design, e.g., British Railways Class 90s. GEC-TPL project managed 406 track kilometres of electrification in Taiwan in 1984. It involved the design, supply and installation of equipment including catenary, substations, telecommunications, locomotives and multiple units. The company also supplied the 134, 3-car trains and project managed the equipment of Lines 3 and 4 of Seoul Metropolitan Subway Corporation. Closer to home, GEC-TPL was the project management company for Phase 1 of the Docklands Light Railway and the Manchester ‘Metrolink’ and supplied the initial vehicles for both systems. In 1987, GEC-TPL contracted to supply the body mounted power equipment for the initial build of Trans Manche Super Trains, later known as ‘Eurostars’, the bar car mechanical parts for which were supplied by its long term partner Metropolitan Cammell which later became part of GEC-TPL in 1989. In 1989, GEC Transportation Projects Ltd became part of the joint company, GEC Alsthom Transportation Projects Ltd., when GEC and Alsthom of France, part of Compagnie Générale d’Electricité (CGE) formed GEC Alsthom. The combined company acquired Metropolitan Cammell at this time. (Alsthom’s name had earlier been derived from ‘Alsace Thomson-Houston’, thereby revealing its earlier parentage from Thomson-Houston of America, as also had the British Thomson-Houston Co., of Rugby, another GEC constituent). In 1998 the company formally changed its name to ALSTOM.

Associated Electrical Industries (AEI) was formed in 1928 as a financial holding company for a number of leading electrical manufacturing and trading companies in the United Kingdom. The two major constituent companies were British Thomson-Houston (BTH) based at Rugby, (Mill Road Works) and Metropolitan-Vickers Electrical Company Ltd (Metrovicks) situated at Trafford Park, Manchester. However, fierce rivalry existed between the Metrovick and BTH brands resulting in internal competition and duplicated management. This was highlighted during the Second World War in 1939, when Metrovicks and BTH became the first two firms in the world to construct jet engines (independently from each other). Following the Second World War, in 1954, AEI expanded to consist of BTH, Metrovicks, Edison Swan Electric Co, Ferguson Pailin, Hotpoint Electric Appliance Co, International Refrigerator Co, Newton Victor, Sunvic Controls, Premier Electric Heaters, Siemens Bros (1955) and Birlec (1954). In 1959 AEI decided to remove the familiar brands of BTH and Metrovicks and consolidate both as AEI resulting in internal problems and a fall in sales and market value. However, AEI acquired a variety of companies from 1959 to 1967, these included Associated Insulation Products, W. T. Henley’s Telegraph Works Co (1958), and London Electric Wire Co and Smiths (1958), Submarine Cables, Hackbridge Holdings Ltd., The Lancashire Dynamo and Crypto Ltd., W.T. Avery Ltd., Henley and Schreiber. The General Electric Company bought AEI in 1967.