Smaller and smaller
The amazing variety of drone shapes, sizes and capabilities reflects the diversity of the missions they are designed to carry out. Some are engineered primarily to provide surveillance, whereas others are armed. There are jet-powered drones nearly as large and fast as commercial airplanes that can be quickly deployed to locations hundreds or even thousands of kilometers away, and large blimps that can sit in the sky for months on end surveying hundreds of square kilometers at a time. But it is the small drones that have the greatest potential to impact national security and privacy, because they can be easily acquired and transported and can be almost undetectable when they fly.
Small drones are already a military operational reality. The Raven drone used by the U.S. military weighs less than two kilograms and is hand-launched by a soldier who simply throws it into the air. Once aloft, it flies to its destination and acquires both conventional color video and night vision–capable infrared video of a target. At the end of a mission it returns and automatically lands itself, after which it can be recovered and readied for its next task. During the summer of 2011, Libyan rebels conducted aerial surveillance using Scout, a 1.4 kilogram, helicopter-like drone made by Canadian company Aeryon Labs.
"Micro-drones" in the laboratory are even smaller. The prototype Nano Hummingbird developed with DARPA support by California-based AeroVironment weighs about 18 grams, has a wingspan of just over 15 centimeters, and has video capability. And Air Force researchers at an Ohio air base have built a "micro-aviary"—an indoor flight laboratory for testing drones being developed there that fly by flapping their wings in the manner of insects.
As technology continues to advance, it will become easier and less expensive to build ever-smaller drones. Small drones can help keep soldiers in the field safe, provide law enforcement officials with an important tool for monitoring crime scenes, and offer search-and-rescue teams a way to rapidly survey an area hit by a natural disaster. If they fall into the wrong hands, however, they can be used for malicious purposes as well.
For most of the history of warfare, getting close enough to carefully scrutinize a target has often meant incurring the risk of becoming one. Armed drones upend this axiom by bringing weaponry close to a target while simultaneously providing high-resolution, real-time video to an operator kilometers away. In the hands of a responsible military this capability is a game-changing asset; in the hands of a rogue group it is a chilling threat.
Much of the security infrastructure that exists today to limit access to sensitive locations has little effect against drones. UAVs can fly over fences and walls and can escape detection by traditional radar systems designed to track larger, passenger-bearing aircraft. Because they can be transported in the trunk of a car or in a backpack, they can be launched from any publicly accessible park, parking lot, city street, river or highway. Once airborne, a drone can arrive within minutes at any location within a few kilometers of the launch site. In short, there is no city, neighborhood or building on the planet that is beyond their reach.