This story originally aired on February 7, 2015. In 1940, the Tacoma Narrows Bridge was a state-of-the-art engineering achievement, a dramatic suspension design spanning a strait of Puget Sound. Sure, it had a bit of a "bounce," but the engineers all assured the public that was normal . Only a handful of bridge workers seemed truly alarmed. Then one day, on November 7, a storm kicked up 40 mph winds, and the bridge began to contort. Soon its undulations took on a distinctive, twisting-ribbon