How Unmanned Aircraft Systems (UAS) and Drones Are Different

The growing aviation sector has spawned a curious alphabet soup of acronyms to describe the various types of unmanned, or remotely-controlled aircraft that grace our skies. News reports describe military drones carrying out surveillance or airstrikes against terrorists around of the world. Companies like Amazon are experimenting with deliveries via drones. And high-tech drones of all shapes and sizes are available to consumers in hobby shops and department stores across the country.

They can’t all be called by the same name can they?

As it turns out, there’s quite a bit of controversy when it comes to terms like drone, UAV (unmanned aircraft vehicle), RPA (remotely-piloted aircraft), and UAS (unmanned aircraft system). So today, we’re taking a look at some of these acronyms to try to make sense of it all.


According to Scientific American, “a drone is an unmanned aircraft that can fly autonomously – that is, without human control.” Yet, the term drone can also be used to describe a variety of vehicles including submarines or even land-based vehicles that operate remotely or autonomously.

The most common use of the term drone, though, according to IoT Agenda is “a flying robot that can be remotely controlled or fly autonomously through software-controlled flight plans in their embedded systems, working in conjunction with onboard sensors and GPS.”

In a nutshell, the term drone is a very generic term that is often used interchangeably with other terminology such as UAV, UAS, or RPA. So anything from a small, remotely-controlled hobby craft to high-tech weaponry used on the military battlefield might be referred to as a drone.

Unmanned Aircraft Vehicle (UAV)

While the terms UAV and drone are often used interchangeably, the term unmanned aircraft vehicle is most often used to describe unmanned remotely-controlled or autonomous vehicles used by the U.S. military or in the commercial sector.

Unmanned aircraft vehicles are typically larger than the drones we’ve seen flying over our favorite beach vacation spot. Most UAVs are piloted by extremely skilled aviators who possess the same skill as those who fly traditional aircraft. In fact many aircraft pilots take exception to the term drone, which fails to communicate the skill involved in flying an unmanned aircraft. The cockpit of many UAVs is laid out in a similar fashion to those of commercial airliners and UAV pilots often take years to master the skills to fly them.

UAVs of various types and sizes are used in a variety of applications in the commercial sector from surveillance and delivery to search and rescue operations, disaster response, wildlife monitoring, fire protection, communications, agriculture, and even healthcare.

Education in unmanned aviation is expanding to meet the demand for these specialized aircraft. Embry-Riddle Aeronautical University, a well-known training ground for the aviation industry, now offers a variety of degree training programs for unmanned systems applications.

Remotely Piloted Aircraft (RPA)

A term preferred by many pilots, RPAs are essentially the same as UAVs. However the term remotely piloted aircraft better communicates the skill level needed to fly most unmanned aircraft. The term RPA was coined by the U.S. Air Force in the latter part of the 2000s to clear up any confusion about the fact that an actual pilot was in control of an unmanned aircraft.

Unmanned Aircraft System (UAS)

The term unmanned aircraft system (UAS) refers to the three components required for any unmanned flight to occur – a remote pilot, an unmanned aircraft, and the connection made between them. Basically, a UAV is a component of a UAS system, which can include a ground station, software, GPS navigation, and communications capabilities. The FAA currently defines UASs as a subset of all aircraft (manned or unmanned). Small unmanned aircraft systems are referred to as sUAS. Unmanned model aircraft that are flown for hobby and recreation are a further subset of sUAS.

FAA Classifications for Pilots

Another way to dispel the confusion surrounding the various terminology is to take a look at how the Federal Aviation Administration (FAA) classifies pilots and the rules regarding how various unmanned aircraft can be flown.

Recreational Users

According the Federal Aviation Administration (FAA), “You are considered a recreational user if you fly your drone for fun, as a hobby.” Drones that weigh more than 0.55 pounds are required to be registered with the FAA. Generally, anyone at least 13 years of age can register a drone for recreational use.

The basic rules include flying at or below 400 feet within a visual-line-of-site (VLOS). This means that you must use your own eyes (with the aid of glasses or contacts if needed) to ensure your drone is in view at all times. See the FAA published guide for complete recreational flight rules.

Commercial Operators

In order to fly a drone or UAV for commercial use, operators must register their drone and become an FAA-certified drone pilot. Regulations regarding commercial flights for drones that weigh less than 55 pounds follow Part 107 of the FAA guidelines for Unmanned Aircraft Systems.

Generally, commercial drone operators must follow many of the same rules as recreational users, keeping a visual-line-of-sight with their unmanned aircraft at all times and operating during daylight hours. Both commercial and recreational drones are typically limited to a maximum altitude of 400 feet and a maximum ground speed of 100 mph (87 knots). Commercial drones may carry payload, but cannot carry hazardous materials.

Advanced Unmanned Aircraft Systems (UAS)

Unmanned aircraft over 55 pounds generally use advanced UAS systems that require years of training to master. Advanced UAS systems are typically used in military drones.

The Future of Unmanned Aircraft

While many experts still aren’t sure of the proper terminology for the growing sector of unmanned aircraft, there’s no doubt that drones, UAVs, and UASs will have a significant impact on our future. In fact, The Association for Unmanned Vehicle Systems International (AUVSI) predicts that the drone industry will generate more than 100,000 U.S. jobs and add $82 billion to the U.S. economy by 2025. Let’s hope that by then, the terminology we use to describe them will be a lot less confusing.

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