The Tacoma Narrows Bridge · 1940
Galloping Gertie
A new bridge moves in the wind. How much risk is too much?
- Ages
- 16 to 18
- Time
- About 20 minutes
- Shape
- 3 decisions and a defense
Part 3 of 3 in the series Engineers on the Line
The situation
The Tacoma Narrows Bridge opened in Washington State in July 1940, with a main span of about 2,800 feet. Its deck used a shallow, solid steel girder, slimmer and cheaper than an earlier, deeper design.
In light winds the deck moved up and down. Local drivers gave it a nickname. Cables and dampers were being studied as fixes.
Your teen leads a consulting team in mid-1940, after the motion was noticed and before any fix is finished.
The background is real. The decisions are an imagined game set in it, so your teen can practice the same kind of reasoning. What really happened is shown only after your teen writes a defense.
What it builds
Deciding how much evidence is enough to act, when the cheap choice and the safe choice differ.
Weighing trade-offs
Names what is gained and lost for each option and chooses on purpose.
Using evidence
Backs each claim with a specific fact from the simulation.
Seeing ripple effects
Traces second- and third-order effects through the system.
Judging risk
Names likely and severe risks and how to reduce them.
Subjects it touches: Engineering, Science, History. It sits beside your core curriculum; it doesn't replace it.
Try the first decision
A short preview. It has no AI and saves nothing. Want two minutes with the background first? Try a mission free
Decision 1 of 3 · Preview, no AI, nothing saved
Map the chain of cause and effect, starting from the design. A shallow girder makes the deck flexible. A flexible deck lets wind-driven twisting grow. Growing twist feeds more motion. Cables and dampers have been tried as partial fixes. The record is incomplete, so you must choose which link to study first.
Opening soon.
Accounts open shortly. Every student gets 15 free tutor messages, enough to try a mission. After that, $888 a year or $88 a month for one student.