1959. There has been a locomotive works at the Southall Depot for nearly 150 years. Originally a Great Western Railway shed, it was possibly the last London steam depot, outlasting Old Oak Common and Stewarts Lane depots. The depot was later used for DMU maintenance and as a base for the electrification programme. Currently the site, now referred to as the Southall Railway Centre, is used by three independent groups, including Locomotive Services (where volunteers can contribute to the preservation and restoration of mainline locomotives). The bus and commercial vehicle manufacturer Associated Equipment Company (AEC) was based in Southall, on a triangular site between Windmill Lane, the main Great Western Railway and the branch to Brentford Dock. The company moved there from Walthamstow in 1926 and closed in 1979 after losing market share whilst part of the giant but inefficient British Leyland group. The site was noticeable to railway passengers and to motorists on Uxbridge Road due to large signs proclaiming "AEC - Builders of London's Buses for 50 years". A major gas works manufacturing town gas was between the railway and the canal. In 1932 a large gasholder was built which has been a landmark from far away. Painted on the north east side of the gasholder are large letters 'LH' and an arrow to assist pilots toward Heathrow Airport's (closed) runway "23" when making visual approaches. The letters were painted in the mid-1960s after a fraction of pilots at a glance mistook RAF Northolt (which has a smaller gasholder under its approach at Harrow). Northolt has a much shorter runway and is not suitable for very large aircraft; one Boeing 707 did land at Northolt by mistake and a number of other aircraft had to be warned off by air traffic control at the last minute. Since such gas production ceased in the 1970s upon tapping natural gas piped from the North Sea, much of the site has been vacant, due to limited road access and remaining gas infrastructure. The 1970s saw racial tensions in the area; in 1976 Sikh teenager Gurdip Singh Chaggar was killed in a racist attack. On 23 April 1979, Blair Peach, a teacher and anti-racist activist, was killed after being knocked unconscious during a protest against the National Front (NF). Another demonstrator, Clarence Baker – a singer of the reggae band Misty in Roots, remained in a coma for five months. More than