One of the first things that confuses people about unmanned aircraft is that there can be so many names and acronyms. How is someone supposed to understand anything about unmanned aircraft and the benefits they provide if it’s not even clear what they are called?
So to make things more clear, here are a few of the most common terms and what they mean:
Perhaps the most recognized and popular term for unmanned aircraft, the name “Drone” has been used for years to apply to a variety of different types of land, sea, or airborne devices. Traditionally the term “Drone” has implied some amount of autonomous control, which means it is not controlled by a pilot but rather by its own decisions or programming. However increasingly the term is being used to apply to remotely piloted aircraft as well.
“RPA – Remotely Piloted Aircraft”
A “Remotely Piloted Aircraft” is an aircraft that is controlled by a pilot not onboard the aircraft. It is not autonomous, and it requires a control link between the pilot and aircraft. This term is more commonly used in Europe and elsewhere around the world than in the United States.
“UAV – Unmanned Aerial Vehicle”
This term was used widely in reference to unmanned aircraft used for military purposes in the 1990’s and early 2000’s. “UAV” is a broad term that can include a wide variety of piloted or autonomous aircraft of any size and design. (One distinction some tried to make was that if these are not called “aircraft”, then some regulations written using the term “aircraft” would not apply.)
“UA – Unmanned Aircraft”
For most professional, government or other legal purposes, the term “Unmanned Aircraft” (UA) has largely replaced UAV. Technically, “UA” refers only to the aircraft itself, and does not include the payload or ground control station.
“UAS – Unmanned Aircraft System”
An “Unmanned Aircraft System” includes all of the components that work together in the operation of an unmanned aircraft. This includes the aircraft itself, its payload (for example, a camera and gimbal), radio transmitters and receivers, and a ground control station.
“sUAS – small UAS”
This term was created to differentiate small unmanned aircraft systems commonly designed and built at the private or hobbyist level from larger UAS (such as those built by aerospace companies or defense contractors). One primary characteristic that usually defines a UAS as “sUAS” is that the total All-Up-Weight of its airborne components not exceed 55 lbs (25kg). Often this is combined with limitations on speed and altitude as well (i.e. 400 feet above ground level).
“Multirotor Helicopter / Multicopter / Quadcopter”
Multirotor helicopters are one type of unmanned aircraft that have become extremely popular to individual hobbyists in recent years due to their capabilities and low cost. They use sensors and microprocessors to independently control multiple horizontal rotors for stable flight, and are usually powered with high-capacity lightweight Lithium Polymer batteries.