Editing AEC Routemaster (section)

==Design==
[[File:RML2551 Halfcab.JPG|thumb|Driver's cab of RML2551]]

The Routemaster was developed between 1947 and 1956 by a team directed by AAM Durrant and Colin Curtis, with vehicle styling by Douglas Scott.<ref>[https://www.independent.co.uk/life-style/swansong-for-the-big-red-bus-londons-pride-the-routemaster-beautiful-efficient-and-simple-to-maintain-is-40-years-old-this-week-but-age-and-galloping-privatisation-mean-its-days-are-numbered-jonathan-glancey-reports-1450242.html Swan song for the Big Red Bus] ''[[The Independent]]'' 22 September 1994</ref><ref>[https://www.telegraph.co.uk/news/obituaries/9590678/Colin-Curtis.html Colin Curtis obituary] ''[[The Daily Telegraph]]'' 5 October 2012</ref> The design brief was to produce a vehicle that was lighter (hence more fuel-efficient), easier to operate and that could be maintained by the existing maintenance practices at the recently opened [[Aldenham Works]], but with easier and lower-cost servicing procedures. The resulting vehicle seated 64 passengers, despite being {{convert|3/4|LT|ST t|spell=in}} lighter than buses in the RT family, which seated 56.

The first task on delivery to service was to replace [[Trolleybuses in London|London's trolleybuses]], which had themselves replaced [[Trams in London|trams]], and to begin to replace the older types of diesel bus. The Routemaster was designed by [[London Transport Executive|London Transport]] and constructed at [[Park Royal Vehicles]], with the running units provided by its sister company AEC. Both companies were owned by Associated Commercial Vehicles, which was taken over by [[Leyland Motors]] in 1962.<ref name=AECSouthall>[http://www.aecsouthall.co.uk/ About AEC] AEC Southhall</ref>

[[File:Heritage Routemaster.jpg|thumb|right|Rear platform of a Routemaster, with updated hand-rails for Heritage Route operation]]

It was an innovative design and used lightweight [[aluminium]] along with techniques developed in aircraft production during [[World War II]].<ref name=londonbookscouk>{{cite web|url=http://www.londonbooks.co.uk/shop/page.php?xPage=articles.html&articleID=1|publisher=Londonbooks.co.uk|title=The Bus We Loved book description 12 September 2006|url-status=dead|archive-url=https://web.archive.org/web/20140221214815/http://www.londonbooks.co.uk/shop/page.php?xPage=articles.html&articleID=1|archive-date=21 February 2014|df=dmy-all}}</ref> As well as a novel, weight-saving integral design, it also introduced for the first time on a bus [[independent suspension|independent front suspension]], [[power steering]], a fully [[automatic gearbox]] and [[Hydraulic brake|power-hydraulic braking]].<ref name=RMAssocHistory/> This surprised some early drivers, who found the chassis unexpectedly light and nimble compared with older designs, especially as depicted on film on tests at the [[Chiswick Works]] skid pan. Footage of RM200 undergoing the skid test at Chiswick was included in the 1971 film ''[[On the Buses (film)|On the Buses]]''.<ref>{{cite web |url=http://www.screen.busesonscreen.net/screen1/index.php?p=screenfm.fmo.onthebusesfilm |title=On the Buses (1972, Reg Varney) |archive-url=https://web.archive.org/web/20120731015953/http://www.screen.busesonscreen.net/screen1/index.php?p=screenfm.fmo.onthebusesfilm |archive-date=31 July 2012 |website=Buses on Screen |url-status=dead}}</ref>

The Routemaster was a departure from the traditional chassis/body construction method. It was one of the first "integral" buses,<ref name=RMAssocHistory/> with a combination of an "A" steel sub-frame (including engine, steering and front suspension) and a rear "B" steel sub-frame (carrying rear axle and suspension), connected by an aluminium body. The gearbox was mounted on the underside of the body structure with shafts to the engine and back axle. Later pre-war London trolleybuses, however, had previously adopted chassisless construction.