Editing De Havilland Comet (section)

===Fuselage===
Diverse geographic destinations and cabin pressurisation alike on the Comet demanded the use of a high proportion of alloys, plastics, and other materials new to civil aviation across the aircraft to meet certification requirements.<ref name=engineering>[http://www.flightglobal.com/pdfarchive/view/1953/1953%20-%200555.html "Comet Engineering: The Performance of Airframe, Engines, and Equipment in Operational Service."] ''[[Flight International]],'' 1 May 1953, p. 551. Retrieved 26 April 2012.</ref> The Comet's high cabin pressure and high operating speeds were unprecedented in commercial aviation, making its fuselage design an experimental process.<ref name=engineering/> At its introduction, Comet airframes would be subjected to an intense, high-speed operating schedule which included simultaneous extreme heat from desert airfields and frosty cold from the kerosene-filled fuel tanks, still cold from cruising at high altitude.<ref name=engineering/>

[[File:De Havilland Comet RAF Museum Cosford (1).jpg|thumb|left|A Comet 1's fuselage and [[de Havilland Ghost]] engine intakes]]
The Comet's thin metal skin was composed of advanced new alloys{{refn|Fuselage alloys detailed in Directorate of Technical Development 564/L.73 and DTD 746C/L90.|group=N}} and was both riveted and chemically bonded, which saved weight and reduced the risk of [[Fatigue (material)|fatigue cracks]] spreading from the rivets.<ref>[http://www.rafmuseum.org.uk/online-exhibitions/comet/comet2.cfm "Comet Enters Service."] {{webarchive |url=https://web.archive.org/web/20090922200849/http://www.rafmuseum.org.uk/online-exhibitions/comet/comet2.cfm |date=22 September 2009}} ''[[Royal Air Force Museum Cosford]]''. Retrieved 1 November 2010.</ref> The chemical bonding process was accomplished using a new [[adhesive]], [[Redux (adhesive)|Redux]], which was liberally used in the construction of the wings and the fuselage of the Comet; it also had the advantage of simplifying the manufacturing process.<ref>Moss, C. J. [http://www.flightglobal.com/pdfarchive/view/1951/1951%20-%200269.html "Metal to Metal Bonding – For Aircraft Structures: Claims of the Redux Process."] ''Flight International'', 8 February 1951, p. 169. Retrieved 26 April 2012.</ref>

When several of the fuselage alloys were discovered to be vulnerable to weakening via metal fatigue, a detailed routine inspection process was introduced. As well as thorough visual inspections of the outer skin, mandatory structural sampling was routinely conducted by both civil and military Comet operators. The need to inspect areas not easily viewable by the naked eye led to the introduction of widespread [[radiography]] examination in aviation; this also had the advantage of detecting cracks and flaws too small to be seen otherwise.<ref>Jefford 2001, pp. 123–125.</ref>

Operationally, the design of the cargo holds led to considerable difficulty for the ground crew, especially [[baggage handler]]s at the airports. The cargo hold had its doors located directly underneath the aircraft, so each item of baggage or cargo had to be loaded vertically upward from the top of the baggage truck, then slid along the hold floor to be stacked inside. The individual pieces of luggage and cargo also had to be retrieved in a similarly slow manner at the arriving airport.<ref>Birtles 1970, p. 132.</ref><ref>Jones 2010, p. 67.</ref>

{{Anchor|Engines}}