Why Elevators Don't Fall (Even When the Cable Snaps)

Elevator cables almost never snap. And even when they do, the car shouldn't fall. In 1854, Elisha Otis stood on a platform above a crowd in New York and told his assistant to cut the only rope holding him up. This is the machine that caught him — and the one hiding above your head every time you ride an elevator: the overspeed governor, the safety gear, and the fail-safe idea behind both. Plus the one day in 1945 when every layer failed at once. Chapters: 0:00 The axe stunt 0:34 One cable, one box? 1:34 What happens if the rope snaps? 3:38 How does a falling elevator know it's falling? 5:23 Why did a brake build the skyline? 6:28 The day every layer failed 8:04 Designed for the moment something breaks Sources: Otis's 1854 Crystal Palace demonstration; rope cut with an axe; 'Al…: https://www.britannica.com/topic/Elis... Safety catch: https://www.encyclopedia.com/people/s... Demonstration date May 30, 1854: https://vtdigger.org/2017/04/16/citie... Otis at a Yonkers bedstead factory in 1852, needed to hoist machinery: https://en.wikipedia.org/wiki/Elisha_... Patent US 31,128 'Improvement in Hoisting Apparatus', Jan 15, 1861: https://patents.google.com/patent/US3... Patent issued less than three months before Otis's death in 1861: https://www.invent.org/inductees/elis... First passenger safety elevator, E.V. Haughwout, 488 Broadway, 1857: https://www.guinnessworldrecords.com/... ASME A17.1: https://www.dir.ca.gov/Title8/3042.html Counterweight = car weight + 40–50% of rated load: https://tkelevator.com/us-en/tools/cl... Overspeed governor, flyweights, trip ~115% for slower cars; safety…: https://www.firgelliauto.com/blogs/me... Governor trip speeds and mechanism: https://patents.google.com/patent/US1... Ascending car overspeed protection and rope grippers (ASME A17.1 §2…: https://www.vantageelevation.com/wp-c... Before elevators, upper floors were the cheapest ('the higher, the…: https://www.timeshighereducation.com/... 1945 B-25 crash into the Empire State Building; 14 deaths; Betty Lo…: https://en.wikipedia.org/wiki/1945_Em... B-25 speed over 200 mph: https://www.smithsonianmag.com/smart-... Oliver's 75-floor fall, all cables incl. safety cable severed; reco…: https://www.guinnessworldrecords.com/... Jumping at the last second doesn't help; lying flat spreads impact: https://www.sciencefocus.com/science/... US elevator/escalator deaths ~31/yr, nearly half workers: https://elcosh.org/document/1232/d000... Images and footage with attribution: Carloferrari (CC BY-SA 4.0): https://commons.wikimedia.org/wiki/Fi... Elisa Rolle (CC BY-SA 3.0): https://commons.wikimedia.org/wiki/Fi... Darklanlan (CC BY 4.0): https://commons.wikimedia.org/wiki/Fi... Elisa Rolle (CC BY-SA 3.0): https://commons.wikimedia.org/wiki/Fi... ООО ТД "Век" (CC BY-SA 4.0): https://commons.wikimedia.org/wiki/Fi... Other images: Pixabay, public domain (Wikimedia Commons, NASA). Music: "Spacial Harvest", "Blue Feather", "Clean Soul", "Evening of Chaos", "Gagool", "Mirage" — Kevin MacLeod (incompetech.com). Licensed under Creative Commons: By Attribution 4.0 — http://creativecommons.org/licenses/b... Some illustrations and reconstructions in this video were generated with AI. Narrated with a synthetic voice. #howitworks #engineering #elevator