Editing Grand Central Terminal (section)

=== Office spaces and control center ===
Upper floors of the terminal primarily hold MTA offices. These spaces and most others in the terminal are not open to the public, requiring key cards to access.<ref name="Ekstein">{{cite news|last=Ekstein|first=Nikki|title=The Untold Secrets of Grand Central Terminal|publisher=Bloomberg L.P.|url=https://www.bloomberg.com/news/articles/2017-02-23/the-untold-secrets-of-grand-central-terminal|date=February 23, 2017|access-date=February 14, 2023|archive-date=March 6, 2021|archive-url=https://web.archive.org/web/20210306212123/https://www.bloomberg.com/news/articles/2017-02-23/the-untold-secrets-of-grand-central-terminal|url-status=live}}</ref> The fifth floor holds the office of the terminal's director, overlooking the Main Concourse.<ref name="Tkaczyk">{{cite news|url=https://www.travelandleisure.com/attractions/landmarks-monuments/grand-central-terminal#catwalk|title=Take a Look Inside Grand Central Terminal Where Most People Never Get to Go|last=Tkaczyk|first=Christopher|date=December 20, 2016|work=Travel and Leisure|access-date=December 21, 2018|archive-date=December 20, 2018|archive-url=https://web.archive.org/web/20181220230338/https://www.travelandleisure.com/attractions/landmarks-monuments/grand-central-terminal#catwalk|url-status=live}}</ref> The seventh floor contains Metro-North's situation room (a board room for police and terminal directors to handle emergencies), as well as the offices of the Fleet Department.<ref name="Roberts2013"/><ref name="Ekstein"/>

Grand Central Terminal has an Operations Control Center on its sixth floor,<ref name="Ekstein"/> where controllers monitor the track [[interlocking]]s with computers. Completed in 1993,<ref>{{harvnb|ps=.|Robins|New York Transit Museum|2013|p=147}}</ref> the center is operated by a crew of about 24 people.<ref>{{cite news|url=https://www.nytimes.com/2009/11/26/nyregion/26gct.html|title=The Zoo That Is Grand Central, at Full Gallop|last=Grynbaum|first=Michael M.|date=November 25, 2009|website=The New York Times |issn=0362-4331|access-date=January 6, 2019|archive-date=January 7, 2019|archive-url=https://web.archive.org/web/20190107021516/https://www.nytimes.com/2009/11/26/nyregion/26gct.html|url-status=live}}</ref> The terminal was originally built with five [[Signalling control|signal control centers]], labeled A, B, C, F, and U, that collectively controlled all of the track [[interlocking]]s around the terminal. The interlockings used to be of [[Interlocking#Electro-mechanical interlocking|electro-mechanical type]], supplied by [[General Railway Signal]] (GRS). Each switch was electrically controlled by a lever in one of the signal towers, where lights illuminated on track maps to show which switches were in use.<ref name="ENR1920 p. 501" /><ref name="RN p. 143" /> As trains passed a given tower, the signal controllers reported the train's engine and timetable numbers, direction, track number, and the exact time.<ref>{{cite news|url=https://www.nytimes.com/1939/09/10/archives/article-9-no-title.html|title=Taming of the Iron Horse|date=September 10, 1939|website=The New York Times |issn=0362-4331|access-date=January 6, 2019|archive-date=January 7, 2019|archive-url=https://web.archive.org/web/20190107015929/https://www.nytimes.com/1939/09/10/archives/article-9-no-title.html|url-status=live}}</ref> In 1993, the original interlockings machines were replaced with 17 GRS VPI [[Interlocking#Electronic interlocking|microprocessors]].<ref>{{cite web|title=A Centennial History of Signaling Inc. Formerly General Railway Signal Company)|archive-url=https://web.archive.org/web/20111002122301/http://www.alstomsignalingsolutions.com/Data/Documents/History.pdf|archive-date=2011-10-02|url-status=dead|url=http://www.alstomsignalingsolutions.com/Data/Documents/History.pdf|accessdate=2024-04-09|publisher=Alstom|page=19}}</ref>

Tower U controlled the interlocking between 48th and 58th streets; Tower C, the storage spurs; and Tower F, the turning loops. A four-story underground tower at 49th Street housed the largest of the signal towers: Tower A, which handled the upper-level interlockings via 400 levers, and Tower B, which handled the lower-level interlockings with 362 levers.<ref name="nyt19130202-1" /><ref>{{harvnb|ps=.|Robins|New York Transit Museum|2013|pp=140, 143}}</ref><ref name="RA1910 p. 620" /><ref name="ENR1920 p. 501" /><ref name="ASCE Metropolitan Section 1902" /> The towers housed offices for the stationmaster, yardmaster, car-maintenance crew, electrical crew, and track-maintenance crew. There were also break rooms for conductors, train engineers, and engine men.<ref name="RN p. 143" /><ref name="RA1910 p. 620" /> After Tower B was destroyed in a fire in 1986, the signal towers were consolidated into the modern control center.<ref>{{Cite news|url=https://www.nytimes.com/1986/09/23/nyregion/grand-central-blaze-damage-to-mean-delays-till-weekend.html|title=Grand Central Blaze Damage to Mean Delays Till Weekend|last=Boorstin|first=Robert O.|date=September 23, 1986|work=The New York Times |issn=0362-4331|access-date=January 5, 2019|archive-date=January 6, 2019|archive-url=https://web.archive.org/web/20190106110003/https://www.nytimes.com/1986/09/23/nyregion/grand-central-blaze-damage-to-mean-delays-till-weekend.html|url-status=live}}</ref>