Why This Bridge Twisted Itself Apart

On the morning of 7 November 1940, a steady 42 mph wind blew across Puget Sound — and the brand-new Tacoma Narrows Bridge, just four months old, began to twist. Within the hour its centre span was at the bottom of the Narrows. You have probably seen the film. What you were told about it is probably wrong. This is the true story of "Galloping Gertie": the fight between two designs, a deck only eight feet deep, the summer people rode it for fun, the professor who tested it in the wind, the last hour minute by minute, the famous film (shown here closer to its true speed) — and why the textbook explanation, resonance, doesn't fit. The real cause was flutter. Because of it, every great bridge is now tested in a wind tunnel before it is built. No person died that day. The only life lost was Tubby, a cocker spaniel. The wreck is now one of the largest artificial reefs in the Pacific Northwest. ⏱ Chapters 0:00 A steady wind 0:57 A bridge across the Narrows 1:55 Two designs 3:43 Galloping Gertie 4:58 The professor 5:49 The last hour 8:54 The film 9:28 Why it really fell 11:46 What changed 13:22 The reef 📚 Sources • WSDOT – Tacoma Narrows Bridge history (1940 bridge, the collapse, eyewitnesses, why it failed, aftermath, weird facts): https://wsdot.wa.gov/TNBHistory/ • K. Y. Billah & R. H. Scanlan, "Resonance, Tacoma Narrows bridge failure, and undergraduate physics textbooks", American Journal of Physics 59 (1991) 118–124 • Physics Today – The Tacoma Narrows Bridge collapse: https://physicstoday.aip.org/quick-st... • ASCE Civil Engineering Source – Professor Farquharson's dog (2023): https://www.asce.org/publications-and... • Golden Gate Bridge – Resisting the twisting: https://www.goldengate.org/exhibits/r... • National Geographic – The Tacoma Narrows Bridge as an artificial reef: https://www.nationalgeographic.com/hi... 🎞 Archive: collapse film by Barney Elliott & Harbine Monroe, The Camera Shop, Tacoma, 1940 (Prelinger Archives, public domain); frames from Prof. F. B. Farquharson's 16 mm film and photographs from Clark Eldridge's final report (HAER, Library of Congress, public domain); University of Washington Libraries Special Collections (no known copyright restrictions); Federal Highway Administration; NOAA Library; Joe Mabel / Wikimedia Commons (CC BY-SA 3.0). Map terrain: AWS Terrain Tiles; coastline © OpenStreetMap contributors. Some scenes are AI-generated reconstructions, labelled "Reconstruction" on screen. Diagrams and maps made with code. Original music. Why It Fell — the true stories behind history's great engineering failures. New story every Saturday. #engineering #history #documentary ◀️ Previous story: The Dam That Failed Hours After It Was Inspected —    • The Dam That Failed Hours After It Was Ins...