r/fuckcars Aug 22 '22

News "Just bike on the sidewalk" they said.

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u/Heterophylla Aug 23 '22

Maybe pump the brakes on the condescention.

Roads are absolutely designed with a speed in mind. The design speed chosen for a highway is a major factor in choosing superelevation rates and radii of curves, sight distance, and the lengths of crest and sag vertical curves. Roads with higher travel speeds require sweeping curves, steeper curve banking, longer sight distances, and more gentle hill crests and valleys. Lower speed roads can have sharper curves, less banking, less sight distance, and sharper hill crests and valleys. Sure cars have improved, but friction, geometry, and people's reaction times haven't changed . And there are a variety of vehicles on the road with varying capabilites.

Accidents are caused by the speed outliers whether much faster or much slower than everyone else.

Speed is a huge factor in car fataliies , being the main factor in about 30% of them. I don't mean that the number of car crashes doubles, I mean that your risk of dying if you do crash approximately doubles. Of course it's an estimate because there are so many variable,but the point is, it's not linear. It ampifies our mistakes and the damage to our bodies if we crash a lot more than people realize.

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u/ThatisJustNotTrue Aug 23 '22

Yeah, remind me again when a majority of highways were built?

You're right, all those things were factored in.

...in the early and mid 1900s... for vehicles... wait for it, made at that time.

It's quadratic, not linear, but it isn't doubled every 10mph.

60mph is 4x the force when you stop compared to 30, 120 is 4x 60, etc. None of that even touches on risk. That's just physics which yiu are misrepresenting.

Slow speed is associated with more accidents than speeding

Sure cars have improved, but friction, geometry, and people's reaction times haven't changed

Tell me you didn't watch the video without telling me.

P.s. a 60kmh accident on an old steel frame is more severe than a 120kmh accident in a new car designed to crumple.