On November 7, 1940, the third-longest suspension bridge in the world began to twist like a ribbon in a mild wind. For hours, "Galloping Gertie" undulated wildly while spectators watched in horror. Then, it tore itself apart and fell into the Puget Sound. The only casualty was a terrified dog named Tubby trapped in a car. This engineering post-mortem explains the phenomenon of aeroelastic flutter (not simple resonance, as often taught). It details the hubris of designers who prioritized slender aesthetics over structural stability and ignored the wind tunnel tests. A definitive guide to why we now build bridges with trusses instead of solid plates, written in the wreckage of bad math.
