4 ms·

Any drone with over 8 propellers already has amazing redundancy today using off the shelf consumer products. Loss of multiple rotors is perfectly manageable.

Any drone with over 8 propellers already has amazing redundancy today using off the shelf consumer products. Loss of multiple rotors is perfectly manageable. Add variable pitch blades and you get autorotation ability to handle total power loss. Worrying about the threats posed is silly. A truck driven by a maniac still can do far more damage. No one is proposing a truck ban.

SlowBro 9y ago
Many drones available today, some of them costing less than USD $1000, could become the kind of flying weapon jra_samba worries about. I just don't think this is a very big concern.
- ShorsHammer 9y ago
  Department13 is where it's at for anyone interested in counterdrone tech. Bigup to dotslash et al. https://department13.com https://department13.com
- jra_samba 9y ago
  Drones don't weigh enough to be a kinetic energy weapon. You'd have to strap a bomb to them (which I believe is getting very popular in certain parts of the world already). A 'flying car' is heavy enough to do large amounts damage just by falling out of the sky. Doesn't have to have anyone riding in it to blow themselves up at the right time, a cell-phone triggered bomb will do just as well.
  - SlowBro 9y ago
    Many drones can carry many kg of load. Any number of heavy (e.g. kinetic) or explosive payloads are an option. Molotov cocktail delivery vehicle? Why not? Requires a remote control lighter and remote release. How about dropping steel rebar? Needs tail fins for directional stability and some testing but that would be plenty troublesome. Drone mounted pistols are already here. (YouTube them.) And yet the skies are considered safe enough today. I just think there are bigger concerns out there.
nradov 9y ago
You're never going to get auto-rotation ability out of an aircraft like that. Even with variable pitch the rotors have insufficient mass. The only practical option is independent dual redundant power systems so that one failure can't take out more than half the propellers. Plus a rocket assisted ballistic recovery parachute to allow a (mostly) survivable crash landing in case of a catastrophic failure. Of course there will still be some rare failure modes where a parachute won't be sufficient.
- ShorsHammer 9y ago
  Autorotation is an immutable property of variable pitch rotors. Whether it can land properly without hurting a person is a physics/biology problem 3rd answer down :) https://aviation.stackexchange.com/questions/37360/can-a-passenger-drone-perform-auto-rotation https://aviation.stackexchange.com/questions/37360/can-a-pas...
908087 9y ago
Being fixed-pitch isn't the only thing that makes autorotation on these impossible. Rotor system inertia is incredibly important in autorotation, and this fact will pretty much make autorotation in quad+-rotor aircraft a no-go. The only option here is a ballistic parachute / BRS, and personally that's not a system I'd stake my life on.

SlowBro 9y ago

Many drones available today, some of them costing less than USD $1000, could become the kind of flying weapon jra_samba worries about. I just don't think this is a very big concern.

ShorsHammer 9y ago
Department13 is where it's at for anyone interested in counterdrone tech. Bigup to dotslash et al. https://department13.com https://department13.com
jra_samba 9y ago
Drones don't weigh enough to be a kinetic energy weapon. You'd have to strap a bomb to them (which I believe is getting very popular in certain parts of the world already). A 'flying car' is heavy enough to do large amounts damage just by falling out of the sky. Doesn't have to have anyone riding in it to blow themselves up at the right time, a cell-phone triggered bomb will do just as well.
- SlowBro 9y ago
  Many drones can carry many kg of load. Any number of heavy (e.g. kinetic) or explosive payloads are an option. Molotov cocktail delivery vehicle? Why not? Requires a remote control lighter and remote release. How about dropping steel rebar? Needs tail fins for directional stability and some testing but that would be plenty troublesome. Drone mounted pistols are already here. (YouTube them.) And yet the skies are considered safe enough today. I just think there are bigger concerns out there.

nradov 9y ago

You're never going to get auto-rotation ability out of an aircraft like that. Even with variable pitch the rotors have insufficient mass. The only practical option is independent dual redundant power systems so that one failure can't take out more than half the propellers. Plus a rocket assisted ballistic recovery parachute to allow a (mostly) survivable crash landing in case of a catastrophic failure. Of course there will still be some rare failure modes where a parachute won't be sufficient.

ShorsHammer 9y ago
Autorotation is an immutable property of variable pitch rotors. Whether it can land properly without hurting a person is a physics/biology problem 3rd answer down :) https://aviation.stackexchange.com/questions/37360/can-a-passenger-drone-perform-auto-rotation https://aviation.stackexchange.com/questions/37360/can-a-pas...

908087 9y ago

Being fixed-pitch isn't the only thing that makes autorotation on these impossible. Rotor system inertia is incredibly important in autorotation, and this fact will pretty much make autorotation in quad+-rotor aircraft a no-go. The only option here is a ballistic parachute / BRS, and personally that's not a system I'd stake my life on.