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mrexroadtoday at 1:16 AM2 repliesview on HN

That’s pretty cool. I’d assumed there would be something similar to the run-away truck ramps you see on steep grades — basically a deep gravel pit. However, actually thinking about it, something along the lines of a gravel pit would likely cause significant damage to engines (not to mention risks created by engine damage) but also seriously impede emergency services.


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Animatstoday at 3:13 AM

These overrun areas aren't that long. This trick is used where there's not enough room for a long overrun area. The high drag has to start fast. With the styrofoam/pumice material, the wheels quickly drop all the way to the hard bottom of the arresting material, and then plow forward, dissipating energy by crushing pumice. With something more solid, the wheels may skim the surface for a while before digging in.

marcosdumaytoday at 1:32 AM

Gravel flies. You can't have it anywhere near an airport runway.

(Some planes have no problem with it, though. You can make even the entire runway of gravel if you only fly those.)

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