• Psythik@lemmy.world
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        10 months ago

        Next time you’re on a flight, download a GPS speedometer app and launch it right before takeoff. You’ll notice that it’ll accurately measure the plane’s speed up to around 500 MPH, before it suddenly stops giving you a speed readout.

        Like the other person said, this is to prevent your average dude building a guided missile using an old phone they have lying around.

          • deur@feddit.nl
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            10 months ago

            Probably would just use an IMU exactly as the plane itself already does for its own navigation.

            They get a lock on the ground, synchronize the IMU with the Earth’s orbit, and they keep track of where they’ve moved from the origin, supplemented by GPS.

    • kent_eh@lemmy.ca
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      10 months ago

      But even if there’s no signal, mobile phone will try to find tower. If it doesn’t find one it will try increasing transmission power.

      Thus draining the phone’s battery much faster.

      Same thing happens if you are camping in a remote location with weak or non-existent coverage.

    • spongebue@lemmy.world
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      10 months ago

      What? Every smartphone I can remember owning has gotten a GPS signal if I hold it up to the window. Plenty of planes have GPS on board too. If there is a speed lockout, a 737 isn’t enough to break that threshold.