Unmanned aircraft have been around since the early 1900s, mainly for military purposes. Not long after the Wright brothers flew at Kill Devil Hills, the British and American aircraft industries became interested in unmanned aviation as a weapon of war.
Drone is a military term that dates back to the early 1930s, when a naval officer used it to refer to an unmanned aerial-targeting vehicle. The military later disowned it, as did the industry that builds [drones] today. But the media love the term.
We first applied the iconic Predator drone in the Bosnian war in 1995, but it really came to the forefront after September 11. Only in the last few years have small drones become a commercial phenomenon.
A lot of it has to do with the miniaturization of electronics and battery chemistry. All of these consumer and smaller commercial drones operate on lithium polymer batteries. The advancement and evolution of GPS, software, and flight controls resulted in very sophisticated machines that you can even get at Best Buy.
The signature small drone that we think of these days is the DJI Phantom, a quadcopter manufactured by a Chinese company. Recreational small drones are good for aerial photography. They now have "follow me" and selfie functions, so you can set the drone to trail you as you walk. On the commercial side, they're very big in the movie industry. They're also used for construction, power line inspection, and by law enforcement.
Privacy is a big issue that hasn't been settled. There are various state laws, but no national regulation that speaks to privacy. The Federal Aviation Administration (FAA) does not allow you to shoot down a drone, even if it's over your property. That is a violation of federal law. Right now, recreational drones are not regulated by the FAA, although you do have to register as an owner for any drone weighing over half a pound. The FAA reported in March that 770,000 drone hobbyists had signed up. It projects the small-model hobbyist UAS (unmanned aircraft system) fleet [will] triple, from an estimated 1.1 million to more than 3.5 million, by 2021.
Last August, the FAA's Part 107 regulation, which pertains to the commercial operation of drones weighing from a half pound to 55 pounds, went into effect. It permits drones to fly up to 400 feet aboveground and requires the drone to remain within your line of sight. You're not supposed to operate over people, and you're not supposed to operate at night, although waivers are available.
There's a lot of buzz around Amazon and drone "package" delivery. I think that's 5 to 10 years off at best, because there are so many issues associated with it. One is collision avoidance. These things have to be able to avoid midair collisions with other aircraft and avoid hitting people on the ground. That's a technology problem that's being addressed. But in terms of having packages delivered to your home, it's a ways off.