The Collapse of Galloping Gertie:
A Revolutionary Turning Point in Suspension Bridge Design
The Wreck
On November 7th, 1940 (around 10:00, PT), the bridge started a lateral twisting motion. It had always moved up and down, but now it was twisting side to side. It had never done this before. Soon, bits of concrete were flying off. The wind tried to pass through the bridge, but the solid plate girders pushed the wind above the bridge, and some below the bridge (Hobbs 64-69). This created a swirling vortex of air, causing the twisting motion. At 11:02, the span crashed.
Side girder ripped away from roadbed after the collapse of the Tacoma Narrows Bridge, November 7, 1940, University of Washington Libraries
Tacoma Narrows Bridge starting to wave at 10:45 a.m., Tacoma Narrows, Washington, November 7, 1940, University of Washington Libraries
Tacoma Narrows Bridge swaying before collapse showing concrete falling into the Tacoma Narrows, November 7, 1940 University of Washington Libraries
"I saw Clark Eldridge, his face white as paper. If I feel badly, I thought, how must he feel."
~ Leonard Coatsworth, Editor for the Tacoma News Tribune