Comment on Future

pyre@lemmy.world ⁨1⁩ ⁨month⁩ ago

• MrFinnbean@lemmy.world ⁨1⁩ ⁨month⁩ ago

  Hmm. This sounds like maths.

  Quick google search say that averag plane weights are about 40 000 kg for small jets, 70 000kg for narrow-body planes and up to 570 000 kg for large wide-body planes.

  While average car weight is somewhere in the 2000 kg mark.

  If the dreams of flying cars come to trough the way most scifi/cyperpunk depicts them and the flight speeds would be at the similiar range than driving on the street.

  So lets be generous and say flying cars would be much hevyer and weight 3000kg and the flight speed would max 175 km/h wich is pretty much the max speed for regular cars.

  Lets go with the average plane so Weight is 70 000kg and flight speed is 930km/h

  So maths:

  E = 0.0386 * m * v^2

  Car: E = 0.0386 * 3 000 * 175^2 ≈ 3.5MJ

  Plane: E = 0.0386 * 70 000 * 930^2 ≈ 2.3GJ

  So you would need about 670 cars to get same impact as one plane.

  *all the numbers came from google-fu and from my ass. Also all the maths was done while sitting on a toilet, so there is large margin for error.

  source

  • pyre@lemmy.world ⁨1⁩ ⁨month⁩ ago

    1. who says you need the same impact? a car can still fly through your window.

    2. I’m not talking about literally recreating 9/11 itself, especially since the twin towers are not as tall as they were. shame. anyway, my point is flying cars make any kind of accident a potential mini-9/11. you can put guardrails on roads, what the hell are you going to have for flying cars?

    source

    • MrFinnbean@lemmy.world ⁨1⁩ ⁨month⁩ ago

      1. Nobody
      2. I just wanted to calculate stuff for fun.

      Talking about the danger. Cars can allready be driven to masses and many houses or businesess dont have any guard railings protecting them from normal cars, but we dont see those happening that much. Why it would suddenly change, by adding additional dimension.

      Also small planes are not really that hard to come by. Why we dont have those driving in to buildings now?

      Also doing “mini-9/11” would most certainly kill or atleast hospitialize the driver. I can somehow understand giving your live for cause you support and cause the enemy lot of pain, but i think there would be much higher treshold to give a life for something that is very unlikely to do anything but structural damage and hurt your self.

      More likelly would be crashing while driving under influence, but i would imagine there would be higher treshold for anybody to fly drunk than drive drunk.

      source

      • pyre@lemmy.world ⁨1⁩ ⁨month⁩ ago

        because there are roads and usually cars stick to those. grip is an important aspect of safety. there’s no grip in the air.

        small planes aren’tn hard to come by? compared to cars? also do you think flying cars are going to use the same routes as planes? what about air traffic control?

        you’re still thinking about my point as deliberate attacks when I’m talking about accidents having much bigger consequences. contrary to your belief there are tons of guardrails, literally or conceptually, around roads. there are no such things in air. if your car goes haywire in the air, it can end up anywhere.

        I’ll concede higher threshold for drunk driving even though I don’t believe it can be enforced reliably. let’s say you can. people still make mistakes while sober. even more when tired. or preoccupied.

        source

        • -> View More Comments