Hollow armed drone 2 fight fires in swarm.bushfires and chemical fires are hard to extinguish. we humans are usually too low in numbers to effectively fight such fires. airplanes go down because they have to fly over at low altitudes in order to drop the water. In hot-cold-air zones. and more then once crash, with painfull loss of the pilots and the costly plane. helicopters are no picknick either.... they have to haul water underneath, as a big weight, wich steers the heli. So i decided thats a too dangerous strategy to extinguish fires.. i started thinking about tanker trucks, wich have bulkheads in the tanks, to reduce the braking weight. apply the same logic to a water-filled drone arm, of wich u need at least 4 to fly. u have now 4 tanker-truck-derived drone arms in your head, Excisting drone designs prove folding is an option. so large scale printing, and towing it behind a firetruck is an option too. So far, we have a neat drone design. but to extinguish a fat fire, u need a lot of water... and flying one drone time after time.. could be quite useless... even if they are bigscale. So thats the point where i introduced triangulation. the tech used to make some drones follow your phone? welll, its arduino, ... so everythings possible... started a year ago,, printed three prototypes allready. none of them float enouh to lift back up after landing on water and filling itself up :( Prototype 4 has hollow drone-arm walls as floats... i will post pics as soon as i have a prototype that actually does what its supposed too :)