Thing is, it has to work over atlantic/pacific/cross north pole routes, etc. We're talking multiple hours and long distance, possibly with a lot of turbulence (

Thing is, it has to work over atlantic/pacific/cross north pole routes, etc. We're talking multiple hours and long distance, possibly with a lot of turbulence (even for GA, which actually gets less steady flight so...). And then it needs to provide guarantees about said navigation, guarantees that those drones do not need.