Guest Post: This article published with permission from our friends at DroneII, Drone Industry Insights. Article authored by Kay Wackwitz.
Air taxis, flying cars and eVTOLs are just a number of the popular names currently being used to refer to unmanned vehicles which are being designed to carry humans in the future. With all these names being thrown around it’s becoming difficult to distinguish between what an air taxi is versus a flying car, whether there can be one name for all of these devices and if so, why all these different names are being used interchangeably? The answer, as always, lies in the details. All of these platforms have one main thing in common: they are designed to carry humans. Therefore, the term that most accurately describes them under one umbrella and without any specification limitations (e.g. regarding energy sources, configuration etc.) is passenger drones.
To help explain why and how this is the case, we’ve built a framework that segments passenger drones according to their features in order to show the different varieties which are available.
What Defines a Passenger Drone?
There are several levels at which it is possible to distinguish between different aerial platforms being designed to carry humans. The very first level is whether they are piloted/manned or unpiloted/unmanned. Looking at our framework all drones which are designed to carry humans but not be piloted are passenger drones.
Important to note here is that even though many platforms aim to fly unpiloted in the future, today they are still manned. In order for this to change, full automation is key. Once truly autonomous solutions are made available and once these are certified according to aviation standards, passenger drones will be able to fly humans with no pilot involvement.
As the industry grows and a private market develops, any passenger drone will also have the option of becoming a private flying device, depending on what market the manufacturer seeks out for their platform. However, given how young the industry still is, this is not yet the case.
Varieties of Passenger Drones
To break down the broad group of passenger drones further we need to look at their energy sources. Almost all unpiloted platforms are powered by electric motors. However, electric energy can either be stored in a battery, or generated by hydrogen (in combination with a fuel cell) or by gasoline/kerosene (in combination with a combustion engine/turbine and a generator).
Finally, in order to break down passenger drones even further the third criteria we need to look at is configuration. These platforms come in three variations: Vertical Takeoff and Landing (VTOL), Short Takeoff and Landing (STOL) and Conventional Takeoff and Landing (CTOL). Each configuration is designed to fit a certain purpose, be it for a longer flight, a heavier load or a more urban operation that lacks a regular runway.
Excluded from this are electrically powered platforms that might utilize the same technology as a passenger drone (e.g. multi-rotor configuration), but require a pilot (e.g. hover bikes, electric aircrafts). There are many examples of hydrogen or gasoline/kerosene powered aircrafts and it’s important to highlight this path towards renewable energy sources. But as they are not unmanned, they should not be mistaken for passenger drones.
What Do All These Other Terms Mean Then?
The more specific terms that often appear in the news, like flying cars, eVTOLs and air taxis are being used because they refer to very specific features and purposes which some passenger drones have.
Air taxis, for example, highlight a specific purpose of a passenger drone: their commercial use to transport passengers in city centers to avoid traffic. Therefore an air taxi cannot at the same time be a personal flying device.
Flying cars highlight a specific feature, that is an aircraft being able to double up as a road-legal car. Due to the major technological and certification hurdles that such a platform must overcome, these designs are thus far very few in number and even those that do exist are all piloted for now. Even though some platforms today may have wheels, these are only used to move the platform around on the ground/airport – not for driving on the street.
Finally, an eVTOL passenger drone represents the group of drones, which are electrically powered and have vertical takeoff and landing capabilities. The term eVTOL describes not just a certain ability of the platform but also that it in order to reduce its ecological footprint in urban areas the eVTOL draws its power directly form an energy storage (battery) without previous transformation.
These key terms are certainly important to being able to understand the differences between the 200+ passenger drone solution designs which already exist. It is also important to stay on top of them, as many more specific terms will likely emerge as more specific uses of passenger drones develop, like for example flying ambulances, airport shuttles and more. In the meantime, this adaptable classification framework is designed to serve as a reference point for understanding this evolving industry.