Editing Avro Vulcan (section)

===Engine===
{{main|Rolls-Royce Olympus}}
[[File:Royal Air Force Museum Hendon (14195378374).jpg|thumb|Air intake integrated in the wing, for the Olympus jet engines]]

The [[Rolls-Royce Olympus]], originally known as the "Bristol BE.10 Olympus",<ref>Baxter 1990, p. 18.</ref>{{refn|Bristol Aero Engines merged with [[Armstrong Siddeley]] in 1959 to form [[Bristol Siddeley]], which in turn was taken over by [[Rolls-Royce Limited|Rolls-Royce]] in 1966.<ref>Baxter 1990, p. 11.</ref>|group=N}} is a two-spool, [[axial-flow]] [[turbojet]] that powered the Vulcan. Each Vulcan had four engines buried in the wings, positioned in pairs close to the fuselage. The engine's design began in 1947, intended to power the [[Bristol Aeroplane Company]]'s own rival design to the Vulcan.<ref>Baxter 1990, p. 13.</ref>

[[File:Bristol Olympus 101 gas flow diagram.jpg|thumb|Gas-flow diagram of an Olympus Mk 101 engine]]

As the prototype Vulcan VX770 was ready for flight prior to the Olympus being available, it first flew using [[Rolls-Royce Avon]] RA.3 engines of {{convert|6500|lbf|kN|abbr=on}} thrust. These were quickly replaced by [[Armstrong Siddeley Sapphire]] ASSa.6 engines of {{convert|7500|lbf|kN|abbr=on}} thrust.<ref>Laming 2002, pp. 45, 46.</ref> VX770 later became a flying test bed for the [[Rolls-Royce Conway]].<ref>Laming 2002, p. 108.</ref> The second prototype VX777 first flew with Olympus 100s of {{convert|10000|lbf|kN|abbr=on}} thrust. It was subsequently re-engined with Olympus 101 engines.<ref>Laming 2002, p. 47.</ref> When VX777 flew with a Phase 2C (B.2) wing in 1957, it was fitted with Olympus 102 engines of {{convert|12000|lbf|kN|abbr=on}} thrust.<ref>Laming 2002, p. 63.</ref>

Early B.1s were equipped with the Olympus 101. Later aircraft were delivered with Olympus 102s. All Olympus 102s became the Olympus 104 on overhaul and ultimately {{convert|13500|lbf|kN|abbr=on}} thrust on uprating.<ref>Baxter 1990, pp. 44–46.</ref> The first B.2 flew with the second-generation Olympus 200,<ref>Baxter 1990, p. 50.</ref> design of which began in 1952.<ref>[http://www.flightglobal.com/pdfarchive/view/1957/1957%20-%200198.html?tracked=1 "16,000 lb Thrust."] ''Flight,'' 15 February 1957, p. 200.</ref> Subsequent B.2s were engined with either the uprated Olympus 201 or the Olympus 301. The Olympus 201 was designated 202 on being fitted with a rapid air starter.<ref>Baxter 1990, pp. 50–64.</ref> The engine would later be developed into a [[reheat]]ed (afterburning) powerplant for the cancelled TSR-2 strike/reconnaissance aircraft and the [[supersonic transport|supersonic passenger transport]] [[Concorde]].<ref name="Buttler p. 72">Buttler 2007, p. 72.</ref>

Around 90% power, the engines in the Vulcan would emit a distinctive "howl"-like noise<ref>[http://www.vulcantothesky.org/news/526/82/We-all-love-the-howl.html "We all love the howl"] {{Webarchive|url=https://web.archive.org/web/20140111044750/http://www.vulcantothesky.org/news/526/82/We-all-love-the-howl.html |date=11 January 2014 }} ''Vulcan To The Sky Trust'', 13 December 2013.</ref>  due to the air intake arrangement, which became an attraction at public airshows.<ref>[http://www.bournemouthecho.co.uk/news/4823500.Will__howl__of_the_Vulcan_bomber_be_heard_over_Bournemouth_again_/ "Will 'howl' of the Vulcan bomber be heard over Bournemouth again?"] The Daily Echo, 30 December 2009.</ref><ref>[https://www.youtube.com/watch?v=H_ARSE8jEHQ "Vulcan XH558 Awesome Howl Sounds"] ''YouTube'', 28 October 2012.</ref>