I wonder how many that have commented on this thread and expressed an opinion have any experience or knowledge of "drones"
Seems to me folks are getting a bit mixed up between security forces type drones (basically remote controlled planes in size) and a hobby type quad/multi copter.
Speaking as someone that owns several Quad/multi copters i can say with a fair amount of confidence that the days of one of these following a backpacker is a longgggggggggggggggg way off.
You'd be lucky to get 20 mins out of a battery as it is, start loading it up with weight and you'll be lucky if one takes off never mind follows you carrying your kit.
It's not like you can use a "throw batteries at it" solution either as the more battery capacity you install the heavier it is, the heavier it is the larger the props and motors, the larger the props and motors the more current draw and so on.
It's not they can glide either, if they're in the air then they are drawing a fair amount of current.
For a quadcopter to lift say 20kg for say 1 hour you are going to need a tremendous amount of super light weight battery power.
No such battery technology exists or is even on the foreseeable horizon.
A plane could at least glide, but again making a plane that can carry 20kg and have enough fuel to spend hours flying just isn't feasible right now.
Plus if you used a plane where would you land it on the side of a mountain?
I've been flying and driving radio controlled devices for the last 30 years, it's rare to go to a club meet and not see a plane, copter, quadcopter fail and/or crash.
So even IF there was some magical battery technology released tomorrow these craft are complex machines with a high failure rate, so they still wouldn't be viable.
So if folks look into the technology rather than the sensationalist media they'll see it really is just a storm in a tea cup

