See, now this is what’s so great about GeekDad: even our advice questions are geeky. Several people have asked about the legality of DIY drones. This is a reasonable question, given that the Aircraft Owners and Pilots Association is complaining about even the police using small drones (such as the CyberScouts, on the left of the picture).
The simple answer is that it’s a bit of a gray area, but the current assumption is that if you stay within the FAA model airplane guidelines (which require you to stay below 400ft and within line-of-sight), you should be okay. But as the technology matures, the number of UAVs in the skies is exploding (we saw a military one cruising at low altitude down the shoreline at Laguna Beach on Friday night), and the FAA is trying to figure out what to do to avoid collisions with other aircraft. In February it published a policy document laying out its current thinking.
The FAA has undertaken a safety review that will examine the feasibility
of creating a different category of unmanned ``vehicles'' that may be
defined by the operator's visual line of sight and are also small and
slow enough to adequately mitigate hazards to other aircraft and persons
on the ground. The end product of this analysis may be a new flight
authorization instrument similar to AC 91-57 [the 1981 rule that allowed
model airplanes to fly lower than 400 ft], but focused on operations which
do not qualify as sport and recreation, but also may not require a
certificate of airworthiness. They will, however, require compliance with
applicable FAA regulations and guidance developed for this category.
Meanwhile, over at FCC there are also regulations on backchannel radio equipment (such as for video feeds). This is easier: anything under 1 watt in open access spectrum such as 2.4 ghz is fine. That can take you as much as three miles if you’ve got a directional antenna on the ground.
As far as our own project goes, we should be well within the 400ft altitude ceiling. We’re also fine on the 1 watt bit for the video backchannel (we’re using 200 milliwatt system from Black Widow AV). Where we might run into to trouble is on line-of-sight control. The current plan is to have an onboard cellphone with bluetooth relaying GPS coordinates as text messages to the Lego Mindstorms NXT controller for waypoint navigation. That means that we can technically fly anywhere that GPS and/or cellphone networks extend. For now, we’ll just restrict the GPS coordinates to line-of-sight locations, but it would be just as easy to fly further and no doubt others will do so.
I hope the FAA allows this. Staying below 400 ft makes sense to avoid conflict with commercial aviation, and there are already restricted areas (such as around airports) that limit flying below that. But for small and light UAVs such as the ones we’re building, I think it’s going to be hard to regulate them much more than that. Many are little more than foam wings, albeit with sophisticated brains, and ours is just balsa wood, steered by an educational toy. If the FBI wants to come after us for weaponizing Lego, that’s a blog post I can’t wait to write.