The '''IBM<!--http://www.dtic.mil/dtic/tr/fulltext/u2/404292.pdf --> 473L Command and Control System''' ('''473L System''', '''473L''' [[colloquialism|colloq.]]) was a USAF{{r|SIedu}} [[Cold War]] "[[Support System|Big L]]" [[Support System]] with computer equipment at [[The Pentagon]] and, in Pennsylvania, the [[Raven Rock Mountain Complex|Alternate National Military Command Center nuclear bunker]]. Each 473L site included a Data Processing Subsystem (DPSS), Integrated Console Subsystem (ICSS),{{r|Brown}} Large Panel Display Subsystem, and Data Communications Subsystem{{r|PRM}} ([[Automatic Digital Network]] interface:<ref name=Singer>{{Cite court |date=December 14, 1977 |litigants=SINGER CO., LIBRASCOPE DIVISION v. UNITED STATES (Cite as 568 F.2d 695) |url=https://books.google.com/books?id=YLGRAAAAIAAJ&dq=IT%26T+473L&pg=PA699 |quote=On October 16, 1962, the System Program Director forwarded to Librascope a draft of the interface specification that had been generated by the SIDG meetings. The accompanying transmittal document requested the 473-L [DPSS] contractor and subcontractors to review the draft specification … L-119 [[Data buffer|buffer processor]]}}</ref> "AUTODIN Data Terminal Bay").{{r|Figure1-2}} The "System 473L" was an "on-line, real-time information processing system designed to facilitate effective management of USAF resources, particularly during emergency situations"{{r|AppendixA}} e.g., for: "situation monitoring, resource monitoring, plan evaluation, plan generation and modification, and operations monitoring".<ref name=TR65-171>{{cite book|url=https://archive.org/stream/bitsavers_mitreESDTe65171AdvancedProgrammingDevelopmentsASur_5291796/ESD-TR-65-171_Advanced_Programming_Developments_A_Survey_Feb65_djvu.txt |title=Full text of "mitre :: ESD Technical Reports :: ESD-TR-65-171 Advanced Programming Developments A Survey Feb65"|access-date=2015-03-08|date=February 1965}}</ref> In 1967, the 473L System was used during the "HIGH HEELS 67" exercise "to test the whole spectrum of command in a strategic crisis".{{r|Wainstein}}{{rp|430}}
