RC helicopters are an amazing class of remote-controlled vehicles. They have an interesting history. RC helicopters began as tools for testing new helicopter design. They then moved into the retail market for model aircraft enthusiasts. Today, they are mainstream as toys and are used by some armed forces as drones. Throughout this transformation, RC helicopters have been experiments for engineers, toys for the public, and weapons for armies. In their first creations, RC helicopters were used by engineers to test new experimental designs. Before remote control equipment was practical for sale to the public, many engineers test their designs in the form of scaled models. Early remote controls for these aircraft would fill the back of an entire truck. They were far too bulky and expensive, even for the most hardcore enthusiasts. The early RC helicopters were expensive as well; the aircraft was not that small, because the receiver equipment and receivers could not be built very small in the 1950s. These aircraft paved the way for the first RC helicopters built for hobbyists and enthusiasts. In the early 1980s, RC helicopters began to be designed for model aircraft enthusiasts. The first models were extremely expensive. These early aircraft were in fact just small productions of late test models. The cost was approximately the cost of a new car. Early retail RC helicopters were gas driven and were quite large; some having a rotor span more than six feet. These RC aircraft paved the way for later toys and weapons. In the last ten years, RC helicopters have become both economical toys and military tools. Today, for 40 US dollars, small battery powered RC helicopters can be purchased. These small battery powered toys are not very fast and cannot fly very long, but they are cheap. There are also a wide range of helicopters for enthusiasts with any size wallet. Some of the more expensive models can travel more than 120 miles per hour and fly for over forty-five minutes. Modern remote controls for these aircraft are small enough to carry in the hands of an average person, a far cry from the oldest remote controls. Modern recreational RC helicopters are wonderful machines. The military has also begun to use RC helicopters as a form of drones. Military drone RC helicopters can be piloted by soldiers at computer terminals halfway around the world. Such drones may carry highly advanced optical equipment and scientific measuring equipment. It has even been rumored that there are armed military RC helicopters. These aircraft could be used for surveillance, spying, and possibly attacks. RC helicopters have come from large machines piloted from controls that fill trucks to toys. They have transformed from simple designs to advanced military machines. They come as small as an egg and nearly as fast as sports cars. They can be bought as cheap toys or expensive enthusiast models. RC helicopters have a future in recreation and war. They are amazing machines.