[RinaseaofDs]

The thing about GPS guided drones is that it is pretty simple to build such a thing.

The vulnerability of GPS in the past was in the accuracy, and so they offered to flavors, one to the military accurate to within 5m, and the other to civiians which would be accurate to within 20m.

Those were the days when people thought you'd use GPS to guide in some sort of missle.

With chem/bio weapons, how accurate do you have to be? Coding a chip to fly a pattern of GPS waypoints and then instaling it in some sort of automated control system is literally a bachelor program project in electrical engineering, third year. We did something very similar with sailboats.

Tougher is finding a UAV with a payload big enough to handle both the fuel and the agent here in the US. Even putting something like that together, you'd have to test it somehow before you use it. This is desperation on SH's part.

Even a Loran C based system would be accurate enough for something like this.

[adx]

Any idea on how fast these drones are? IIRC, don't commercial GPSs cut out if the receiver is moving too quickly (built in to prevent the use of commercial GPS for this very thing?)? Also, I'd probably use more than one means of getting positional data (like RinaseaofDs wrote, use Loran C or a similar radio direction-finding method). The skill level needed to do systems integration is pretty much EE undergrad/entry-level BSEE stuff.

[Amerigomag]

Tougher is finding a UAV with a payload big enough to handle both the fuel and the agent here in the US

If you knew that the "fuel" is 6 to 8 lithium polymer batteries (cell phone batteries) and the "payload" is a 12 to 24 oz. aerosol can, the problem becomes a bit simpler to resolve.

Don't you think?

[Myrddin]

Even a Loran C based system would be accurate enough for something like this.

I worked with lobster fisheren in the late 70's that claimed Loran C was so good that if they simply matched the values on the display where they originally dropped their lobster pots, they could toss the hook over the side and retrieve the pots reliably. It was much easier with the digital displays vs the old Loran A CRTs where you had to mess with matching rep rates and analog waveforms.