Editing Northrop B-2 Spirit (section)

===Overview===
The B-2 Spirit was developed to take over the USAF's vital penetration missions, allowing it to travel deep into enemy territory to deploy [[aircraft ordnance|ordnance]], which could include [[nuclear weapon]]s.<ref name= "croddy 341-2">Croddy and Wirtz 2005, pp. 341–342.</ref> The B-2 is a [[flying wing]] aircraft, meaning that it has no fuselage or tail.<ref name= "croddy 341-2"/> It has significant advantages over previous bombers due to its blend of low-observable technologies with high aerodynamic efficiency and a large payload. Low observability provides greater freedom of action at high altitudes, thus increasing both range and field of view for onboard sensors. The USAF reports its range as approximately {{convert|6000|nmi|mi km|lk=in}}.<ref name=B-2_AF_fact_sheet/><ref name=Spick_p340-1>{{harvnb|Spick|2000|pp= 340–341}}</ref> At cruising altitude, the B-2 [[aerial refueling|refuels]] every six hours, taking on up to {{convert|50|ST|kg}} of fuel at a time.<ref name="chiles201309" />

The development and construction of the B-2 required pioneering use of [[computer-aided design]] and [[computer-aided manufacturing|manufacturing]] technologies due to its complex flight characteristics and design requirements to maintain very low visibility to multiple means of detection.<ref name= "croddy 341-2"/><ref>{{harvnb|Sweetman|2005|pp=73–74}}</ref> The B-2 bears a resemblance to earlier Northrop aircraft; the [[Northrop YB-35|YB-35]] and [[Northrop YB-49|YB-49]] were both flying wing bombers that had been canceled in development in the early 1950s,<ref name= "boyne 466">{{harvnb|Boyne|2002|p=466}}</ref> allegedly for political reasons.<ref>{{harvnb|Fitzsimons|1978|p=2282}}</ref> The resemblance goes as far as B-2 and YB-49 having the same wingspan.<ref>Noland, David. "[http://www.infoplease.com/spot/northropb2.html Bombers: Northrop B-2] {{Webarchive|url=https://web.archive.org/web/20140425004938/http://www.infoplease.com/spot/northropb2.html |date=25 April 2014}}" ''Infoplease'', 2007. Retrieved 24 April 2014.</ref><ref>"[http://www.military-heat.com/42/b2-spirit-stealth-bomber/ The B-2 Spirit stealth bomber] {{Webarchive|url=https://web.archive.org/web/20140425004903/http://www.military-heat.com/42/b2-spirit-stealth-bomber/ |date=25 April 2014}}" ''Military Heat'', 2007. Retrieved 24 April 2014.</ref> The YB-49 also had a small [[radar cross-section]].<ref>{{Cite web|url=https://fas.org/nuke/guide/usa/bomber/b-49.htm|title=B-49 – United States Nuclear Forces|access-date=29 July 2018|archive-date=26 March 2019|archive-url=https://web.archive.org/web/20190326095032/https://fas.org/nuke/guide/usa/bomber/b-49.htm|url-status=live}}</ref><ref>{{Cite magazine |last=Heppenheimer |first=T. A. |date=September 1986 |title=Stalth – First glimpses of the invisible aircraft now under construction |url=https://books.google.com/books?id=NUzwukoJzGIC&q=YB-49+radar&pg=PA76 |magazine=Popular Science |page=76 |access-date=27 October 2020 |archive-date=5 February 2021 |archive-url=https://web.archive.org/web/20210205101204/https://books.google.com/books?id=NUzwukoJzGIC&q=YB-49+radar&pg=PA76 |url-status=live}}</ref>

Approximately 80 pilots fly the B-2.<ref name="chiles201309" /> Each aircraft has a crew of two, a pilot in the left seat and mission commander in the right,<ref name=B-2_AF_fact_sheet/> and has provisions for a third crew member if needed.<ref>{{cite web|title=B-2 Spirit Stealth Bomber Facts|url=http://www.northropgrumman.com/Capabilities/B2SpiritBomber/Documents/pageDocuments/B2-Fact-Sheet.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.northropgrumman.com/Capabilities/B2SpiritBomber/Documents/pageDocuments/B2-Fact-Sheet.pdf |archive-date=9 October 2022 |url-status=live|publisher=[[Northrop Grumman]]|date=14 March 2007|access-date=15 June 2016}}</ref> For comparison, the B-1B has a crew of four and the B-52 has a crew of five.<ref name=B-2_AF_fact_sheet/> The B-2 is highly automated, and one crew member can sleep in a [[camp bed]], use a toilet, or prepare a hot meal while the other monitors the aircraft, unlike most two-seat aircraft. Extensive [[sleep cycle]] and [[fatigue (safety)|fatigue]] research was conducted to improve crew performance on long sorties.<ref name="chiles201309" /><ref name="tirpak199604">{{cite journal |url=http://www.airforcemag.com/MagazineArchive/Pages/1996/April%201996/0496bomber.aspx |archive-url=https://web.archive.org/web/20131112190523/http://www.airforcemag.com/MagazineArchive/Pages/1996/April%201996/0496bomber.aspx |archive-date=12 November 2013 |title=With the First B-2 Squadron |author=Tirpak, John A. |journal=Air Force Magazine |date=April 1996 |volume=79 |issue=4}}</ref><ref>Kenagy, David N., Christopher T. Bird, Christopher M. Webber and Joseph R. Fischer. [http://www.ingentaconnect.com/content/asma/asem/2004/00000075/00000005/art00001 "Dextroamphetamine Use During B-2 Combat Mission."] {{Webarchive|url=https://web.archive.org/web/20131112181039/http://www.ingentaconnect.com/content/asma/asem/2004/00000075/00000005/art00001 |date=12 November 2013}} ''Aviation, Space, and Environmental Medicine'', Volume 75, Number 5, May 2004, pp. 381–386.</ref> Advanced training is conducted at the [[USAF Weapons School]].<ref name="isis">{{cite magazine |magazine=[[The Atlantic]] |title=An Extraordinarily Expensive Way to Fight ISIS |archive-url=https://web.archive.org/web/20180627111647/https://www.theatlantic.com/magazine/archive/2018/07/william-langewiesche-b-2-stealth-bomber/561719/ |archive-date=27 June 2018 |url=https://www.theatlantic.com/magazine/archive/2018/07/william-langewiesche-b-2-stealth-bomber/561719/ |first=William |last=Langewiesche |date=July 2018}}</ref>