It is not uncommon that, for one reason or another, drones are mentioned (more or less correctly) in the media, on social networks and even in our everyday conversations as an example of technological progress, as a platform for a potential future application and even as protagonists in films or video games. However, we use the term without knowing what it really means and without paying attention to more precise designations that exist for unmanned aircraft today.
You may also, on more than one occasion, have heard or used other terms such as RPAS, RPA, UAS, UAV, ART, UAV, UAV or some other similar term to denote an RPAS, RPA, UAS, UAV, ART, UAV or other similar term. unmanned aircraft and the system of which it forms part, i.e. everything that goes with it.
Everyone will understand when you use the word «drone», but if you want to convey a technical, modern and concise message, it is better to use more appropriate terms such as RPAS.
But what is the correct term? In this article, we will try to clarify in a simple way how an unmanned aircraft is defined and what is the difference between drone, UAV, UAS and RPAS?.
Characteristics of an unmanned aircraft
The definition of an unmanned aircraft is obvious: an unmanned aircraft is a air vehicle capable of flying without a pilot on board. Unmanned aircraft or UAVs can fly autonomously thanks to a computer installed in them or, in the most common case, they may be controlled remotely by a pilot.
In any case, for an unmanned aircraft to function, has to be part of a system, a UAS, which is composed of at least three fundamental parts: the aircraft itself, a ground control centre and the communications link between the two (including sensors, electrical connections, GPS, cameras, etc.).
Unmanned aircraft have multiple applications, These range from surveillance and observation, to solutions to improve connectivity in rural areas or efficiency in agriculture.
To understand the origin of these unmanned aerial vehicles or drones, three preliminary notes must be made:
- Drones have a military origin.
It is only since the recent democratisation of drone technology that drones have also found a place in the civilian sector. For this reason, the designation used is often of military origin.
- There are differences between the type of control of most civil or industrial drones and most military or security drones.
The drones for civil or industrial use The most common are tools with the sole task of tirelessly collecting data in an automated way. This task is programmed in advance with a clear objective: to make an efficient flight pattern in order to accomplish it in the shortest time possible. Anything that deviates from its programmed flight plan is a waste of time and therefore efficiency. This machine is continuously supervised by a human, but active human intervention (i.e. taking the machine out of the automated execution of its programme to control it manually) during this type of flight is considered detrimental, as it loses efficiency. It is therefore a remotely supervised aircraft with a rigid and perfectly established objective. It is a scheduled and continuously monitored flight. The operator does not normally need to fly the aircraft, although some operators do need to fly the aircraft during take-off and landing.
On the other hand, the military drones and in general all surveillance/security related uses are the opposite of the above. The objective of the flight is developed during the flight itself. as expected events arise (or not) (e.g. the detection of an intruder and its subsequent tracking requires modifying the flight plan to adapt to this new circumstance). Therefore, this type of flight requires a human pilot who not only supervises the flight, but also manually modifies it according to the needs of the mission. It is, therefore, a remotely piloted aircraft with a variable and flexible objective that is configured according to the development of the mission. It is a manually controlled flight and is continuously monitored and piloted by a human. Obviously there are cases where the two types of control are mixed, but it is normal for most of the flight to be of one type or the other (programmed or manual control).
- Drones for specific and recreational work.
It is necessary to clearly differentiate drones which are aerial devices that perform a specific job for a specific mission (commercial, security, support or other in the civil and military sector or even intelligence in the defence sector) from all those recreational or hobby flying devices which do not really fulfil any function other than the entertainment of their users (model aircraft and toys).
Differences between drone, UAV, UAS and RPAS
Having seen these principles, let's look at the main denominations one by one:
Dron:
If we look up the definition of ‘drone’, we will see that it is indeed, according to the RAE (Royal Spanish Academy of the language), an “unmanned aircraft”.
It is the most common and widespread name, But it is also the most generalising, least technical and least liked by professionals in the sector.
Drone literally means “drone” in English and although there are many people who attribute this origin to the possible similarity between the flight of the insect and the machine, the reality is that the word has a second meaning which means “buzzing”. It is this meaning that is most likely to have come to be used to designate these machines, as they are normally only detectable by their persistent “buzzing”.
This term encompasses anything that moves through the air with a minimum of steering capability and no other criteria than having a pilot on board. It is a term especially used to saturation point in films. For this reason, it is massively transferred to the general population and is also used indiscriminately. If you work in the industry, you will probably shy away from this term because it is not very technical.
Try not to use it, as there are much more technical expressions such as the ones below.
This expression is often used in reference to multicopters and toys.. For this reason, users and manufacturers of larger and more complex systems are not very likely to use it.
If possible, do not use this term, unless you are addressing a general audience with little knowledge of this technology.
UAV: Unmanned Aerial Vehicle
Literally means Unmanned Aerial Vehicle. UAV “Unmanned Aerial Vehicle” is also used in many Latin American countries, but curiously, not in Spain.
This term was one of the first to be used for unmanned aircraft and since it originated in the military sector, it is still a term that is deeply rooted in that environment.
This term was intended to clearly differentiate between those aircraft that had a pilot inside and those that did not. This is particularly relevant when working in operational scenarios and transmitting commands in environments that include UAVs and manned aircraft. In an operational scenario, UAVs needed to be well identified so that pilots working with them would know what to expect from them, both in terms of responses and behaviour.
This term implies that the aircraft is not manned by a human.. In fact, it implies that the aircraft may be unmanned in any way and, therefore, this term is particularly associated with scheduled flight aircraft. This means that the aircraft is self-controlled and controlled by a programme already established and loaded into its memory prior to flight (continuously supervised flight).
This programmed and continuously supervised pattern of action is often flown by, above all, small aircraft engaged in civilian data collection work such as topographic surveys.
This term is still widely used, although it is considered somewhat old and not very descriptive, and is losing ground in favour of the term RPA, which will be discussed later. It defines industrial civil aircraft very well, but these are also covered by the term RPAS for regulatory reasons, as the regulation today makes no distinction between remotely piloted and remotely supervised aircraft.
It is correct to use this term when referring to scheduled aircraft. It can also be used colloquially and generically in defence environments (although less and less accepted) or with veteran aerospace people who still use it.
As a special derivative of this term there is the term UCAV (Unmanned Combat Aerial Vehicle). It is the same as a UAV, but with the particularity that the aircraft is only intended for aerial combat. These aircraft are still under development and although they have even taken off and landed on aircraft carriers (such as the X-47 model), their limited ability to make autonomous decisions combined with the difficulty of having good situational awareness (situational awareness) means that they still depend on a human pilot on the ground to fly them. In parallel, manned fighters (such as the F-16) are being tested as an equally viable technology, but with less need for development, incorporating all the electronics and communications to be piloted remotely.
UAS: Unmanned Aircraft System (unmanned aircraft system)
It is a refinement of the term UAV that covers all elements of the system (the term UAV only refers to the aircraft), i.e. ground station, sensors, communication antennas, etc.
This term is more appropriate than UAV when one refers to the whole (which is usually the norm) and not strictly to the aircraft.
Use this term to refer to the complete system (aircraft and everything around it) when talking to someone in the same cases as with UAV. Like UAV it is a term in progressive disuse.
RPA: Remotely Piloted Aircraft (remotely piloted aircraft)
This is the most current definition. ART, “Aeronave Remotamente Tripulada” (Remotely Manned Aircraft) is also used in many Latin American countries, but curiously, not in Spain.
Its origin is due, in large part, to the need to convey the positive idea that there is a human supervising or performing the actions behind the machine, as opposed to the term UAV which somehow does not give clarity in that sense.
Use this term when you want to refer in a technical and accurate way to an aircraft that is normally being actively manned/piloted (not only monitored) from its ground control centre.
RPAS: Remotely Piloted Aircraft System (remotely piloted aircraft system)
This is the most widely used and most widely accepted technical term today for all systems containing a continuously piloted and monitored aircraft. As a further development of the term RPA, it is used when referring to the complete system, i.e, not only includes the aircraft, but also all subsystems accompanying it such as ground station, communications, etc.
Some experts believe that the definition RPAS is actually a subclass of UAS because they consider that all drones fulfil the characteristic of having no crew on the aircraft and RPAS simply denotes that, in addition to not having a human on board, it is also actively piloted remotely. However, to be strict, no drone is unmanned, as the crew is either acting remotely or supervising the mission.
Use this term when you are in a technical and professional environment. You can use it for all airborne systems both continuously supervised and continuously piloted indifferently, although it is appropriate to use it only for continuously piloted and not for continuously supervised... But for that we will have to wait for the definitions to be updated again with new ones. In the meantime, we have to work with the existing ones.
In short, you can use any term you want to talk about an unmanned aircraft, drone, UAV, UAS or RPAS; there is no limitation to it (not even at a legal level). Everyone will understand you when you use the word drone and the important thing is that you make yourself understood to your audience. But if you want to convey a technical, modern and concise message It is better to use more appropriate terms such as RPAS.
