Why the Tacoma Narrows Bridge Really Collapsed

On July 1, 1940, the Tacoma Narrows Bridge opened as the third-longest suspension bridge in the world. 129 days later, a wind of about 40 mph tore it apart. This video explains what actually happened, minute by minute, why it was not simple resonance, and what engineers changed afterward. In this video: • Why the original 25-ft truss design was swapped for 8-ft plate girders • Why the bridge was nicknamed Galloping Gertie • The fixes that failed, and the five days that were left • The morning of November 7, 1940, from 10:03 to 11:02 a.m. • Resonance vs. aeroelastic flutter, in plain language • What wind tunnel testing changed for every long bridge since CHAPTERS 0:00 The bridge that lasted 129 days 0:20 Building the Narrows bridge 0:40 How a suspension bridge works 1:00 The cheaper design 1:50 Too thin for its length 2:10 Galloping Gertie 2:20 The fixes that failed 2:50 Five days left 3:00 The morning of November 7 3:50 10:03: the bridge starts to twist 4:50 The collapse 5:10 Resonance vs. flutter 5:40 Why the deck's shape mattered 6:00 The investigation 6:20 Warnings 6:40 Sturdy Gertie 7:10 Wind tunnels today 7:20 The lesson Safety Factor tells the stories of engineering failures and the lessons they left behind. New videos regularly. Subscribe so you don't miss the next one. Disclosure: Illustrations and narration in this video were created with AI tools. Facts were checked against the sources above. Diagrams are schematic and not to scale. #TacomaNarrowsBridge #GallopingGertie #EngineeringFailures