4 ms·

How will the drones handle bad weather if they're continuously operational? They're not really quick so they can't outrun all kinds of weather.

• dfbrown 13y ago
  Is there much weather at 65000 ft?
  • knappe 13y ago
    At that height you can see the curvature of the Earth. For perspective here is a picture: http://imgur.com/I5qQA3D http://imgur.com/I5qQA3D EDIT: Fair point. The max height on cumulonimbus clouds are 60,000 feet[0]. Effectively there is zero weather. [0] - http://en.wikipedia.org/wiki/Cumulonimbus_cloud http://en.wikipedia.org/wiki/Cumulonimbus_cloud
    • tfe 13y ago
      To be fair, in a lot of those "curvature of the earth" pictures, the apparent curvature comes from the wide-angle lens more than actual curvature of the earth.
  • marvin 13y ago
    Not really. Thunder clouds usually top out around 60.000 feet. There are some wind phenomena that could reach this high, but mostly I think it's calm at this altitude. The air is so thin you would have to have very strong winds for there to be a problem.
    • marcosdumay 13y ago
      That's what makes me wonder... How will they keep a plane flying at that altitude at 68mph? The thinner the air, the faster your plane must move. (Ok, 250lbs is not that much weight, but you must add the plane's weight. And it does not have huge wings.)
      • PhasmaFelis 13y ago
        The hypothetical craft with the 250lb payload has a wingspan almost as wide as a 747's.
      • marvin 13y ago
        Aerodynamic lift (in Newtons) is proportional to airspeed and invesely proportional to air pressure. So is aerodynamic drag. This holds true up to the transsonic region; ~800 kph of true airspeed. As long as you're subsonic, it's sufficient to have the same amount of thrust as at low altitudes, and you'll keep flying at the speed required for lift >= aircraft weight. Granted, this will require proportionally higher propeller RPM, but with electric engines this is unproblematic. You'd get in trouble with hydrocarbon engines though, since you need the same amount of oxygen to generate power. So at altitude, you'd need a turbocharger or similar machinery.
    • mik4el 13y ago
      Cool, thx =)