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150 knots is like 77 meters a second, a 747 can do like 2m/s^2 braking giving 35 seconds to stop, 1500 meters required.

Stopping time: t=v/a, t=77/2. Stopping distance: d=v^2/2a, d=77^2/2*2




Now account for the fact that the plane had no brakes since the landing gear were not deployed ...


A hull rolls better than a wheel? Has humanity been doing vehicles wrong this entire time?


Snarky and ignorant, the two often come together.

Because you seem unaware: Airplane wheels have very powerful brakes!


Even if they lock completely, they'll skid more than the entire hull's skidding no?


The trick is not to lock and use static friction. https://en.m.wikipedia.org/wiki/Stiction

Hm, the stiction page on Wikipedia does not explain how it relates to braking. Maybe check out https://en.m.wikipedia.org/wiki/Threshold_braking


Thanks for the link. Nowhere it seems to indicate that the friction of the breaking would be greater than the friction of the hull, since the pages related to non-destructive braking.


Airplanes use disc brakes. These can provide pretty much unlimited friction and are very destructive to the brake pads. They are effectively limited by the static friction of the tire and how much waste heat they can dissipate without blowing the tire.

Look it feels like you want to win an argument. You can only win it for people who do not understand the difference between static friction of a tire on tarmac and kinetic friction of a hull on tarmac. I couldn't tell you off-hand which has more friction, but I'm ready to believe by example that the hull has bad properties when it comes to braking. It's made for low friction after all.


(That's with brakes and flaps.)




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