Editing Concorde (section)

===Brakes and undercarriage===
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 |image_caption2= Tail bumper of Concorde G-BOAG at the [[Museum of Flight]] in Seattle
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Because of the way Concorde's delta-wing generated lift, the undercarriage had to be unusually strong and tall to allow for the angle of attack at low speed. At [[Rotation (aviation)|rotation]], Concorde would rise to a high angle of attack, about 18 degrees. Prior to rotation, the wing generated almost no lift, unlike typical aircraft wings. Combined with the high airspeed at rotation ({{convert|199|knot|disp=or}} [[indicated airspeed]]), this increased the stresses on the main undercarriage in a way that was initially unexpected during the development and required a major redesign.<ref>{{cite web |url=http://www.iasa.com.au/folders/Safety_Issues/others/concordespacer.html |title=The real story of Flight 4590: Special Investigation |publisher=iasa.com.au |date=13 May 2001 |first=David |last=Rose |access-date=26 June 2007 |archive-url=https://web.archive.org/web/20100207121508/http://www.iasa.com.au/folders/Safety_Issues/others/concordespacer.html |archive-date=7 February 2010 |url-status=dead}}</ref> Due to the high angle needed at rotation, a small set of wheels was added aft to prevent [[tailstrike]]s. The main undercarriage units swing towards each other to be stowed but due to their great height also needed to contract in length telescopically before swinging to clear each other when stowed.<ref>Brooklands Museum</ref>

The four main wheel tyres<!-- please leave British spelling of "tyres" on British/French aircraft ---> on each [[bogie]] unit are inflated to {{convert|232|psi|kPa|abbr=on}}. The twin-wheel nose undercarriage retracts forwards and its tyres are inflated to a pressure of {{convert|191|psi|kPa|abbr=on}}, and the wheel assembly carries a spray deflector to prevent standing water from being thrown up into the engine intakes. The tyres are rated to a maximum speed on the runway of {{convert|250|mph|km/h|abbr=on}}.<ref>After the Paris accident in 2000 Concorde was fitted with improved tyres uprated to {{cvt|290|mph}}.</ref>

The high take-off speed of {{convert|250|mph|km/h}} required Concorde to have upgraded brakes. Like most airliners, Concorde has [[anti-lock braking system|anti-skid braking]]&nbsp;to prevent the tyres from losing traction when the brakes are applied. The brakes, developed by [[Dunlop Rubber|Dunlop]], were the first carbon-based brakes used on an airliner.<ref>{{cite journal |title=Design and Engineering of Carbon Brakes |author=Stimson, I.L. |author2=R. Fisher |volume=294 |issue=1411 |date=January 1980 |pages=583–90 |journal=Philosophical Transactions of the Royal Society of London |jstor=36383 |bibcode=1980RSPTA.294..583S |doi=10.1098/rsta.1980.0068|s2cid=122300832}}</ref> The use of carbon over equivalent steel brakes provided a weight-saving of {{convert|1200|lb|kg|abbr=on}}.{{sfn|Owen|2001|p=118}} Each wheel has multiple discs which are cooled by electric fans. Wheel sensors include brake overload, brake temperature, and tyre deflation. After a typical landing at Heathrow, brake temperatures were around {{convert|300|-|400|°C|°F|abbr=on|sigfig=2}}. Landing Concorde required a minimum of {{convert|6000|ft|m|abbr=out}} runway length; the shortest runway Concorde ever landed on carrying commercial passengers was [[Cardiff Airport]].<ref>{{cite news|title=Concorde takes off from Cardiff|url=http://news.bbc.co.uk/1/hi/wales/3118506.stm|publisher=BBC|access-date=19 January 2016|date=18 September 2003|archive-date=23 July 2004|archive-url=https://web.archive.org/web/20040723172418/http://news.bbc.co.uk/1/hi/wales/3118506.stm|url-status=live}}</ref> Concorde G-AXDN (101) made its final landing at [[Duxford Aerodrome]] on 20 August 1977, which had a runway length of just {{convert|6000|ft|m|abbr=out}} at the time.<ref>{{Citation |title=Concorde 101 {{!}} On board with a Test Engineer | date=27 April 2022 |url=https://www.youtube.com/watch?v=nh3ty6wp6qQ |language=en |access-date=27 April 2022}}</ref><ref>{{Cite web |title=Concorde G-AXDN (101) |url=https://www.heritageconcorde.com/g-axdn-101 |access-date=27 April 2022 |website=heritage-concorde |language=en}}</ref> This was the last aircraft to land at Duxford before the runway was shortened later that year.<ref>{{Cite news |date=25 August 1977 |title=Concorde lands safely at Duxford |work=Saffron Walden Weekly News |url=https://www.newspapers.com/article/saffron-walden-weekly-news-concorde-land/136696156/ |via=[[Newspapers.com]]}}</ref>