C H A P T E R

N ° 31

Autonomous Aircraft

Activities occurring on the Sun (i.e., solar activity) can create space weather influencing the performance and reliability of space-borne, air-borne, and ground-based technological systems. Additionally, in some instances, it can even endanger human life and health. The future indicates an ever-growing dependency on advanced technologies to enable a plethora of services and capabilities. This is especially within critical infrastructures like the aviation industry, which is on a trajectory to provide fully autonomous air vehicles (aircraft) in the future.

Some aircraft are already close to being semi-autonomous. Modern aircraft, particularly long-haul airliners, utilize semi-autonomous systems. These systems are used for much of the routine flight tasks, allowing pilots to focus on more complex aspects of flight and contingency management. While fully autonomous flights are still in development for commercial aircraft, the technology for semi-autonomous and even fully autonomous flight already exists. 

In Hoplon’ articles; C H A P T E R  N ° 27-30, we provide an introduction to the relation between space weather and the aviation industry, exploring the interaction between space weather and the Earth’s natural planetary defence systems, avionics, and aircrews. Additionally, we discuss the associated risks of financial losses caused by space weather impact and some of the currently available mitigation measures. Lastly, we discuss the effectiveness of radiation protection measures for aircrews and aircraft.

Today’s article will be the first of four articles focused on exploring the topic of autonomous aircraft and how space weather may affect them. Throughout this mini-series, we will look closer at how autonomous aircraft are classified and how they work. Additionally, we will discuss the risks and vulnerabilities of such inventions starting by looking at how space weather interacts with the data transferring process from satellites to receivers on ground and in air. Moreover, we will look at specific space weather impacts on aircraft comparing modern and autonomous air vehicles, and provide examples. Lastly, we will look closer at some of the currently available mitigation measures and the complexity of mitigation measure for autonomous vehicles.

Image Credit: Freethink; Droneliner.

Autonomous Aircraft

Modern aircraft rely heavily on automation and autopilot systems, allowing for significant portions of flight to be handled without constant pilot input. Autonomous aircraft, on the other hand, are designed to operate with a higher degree of independence, potentially reducing the need for human pilots in the cockpit. While both types of aircraft utilize advanced technology, autonomous aircraft represent a step further in automation, potentially leading to increased efficiency and cost savings. 

Autonomous aircraft are airplanes, helicopters, or other flying vehicles that can operate without direct human control (i.e., a pilot onboard the aircraft). They utilize advanced technologies relying on sophisticated software and algorithms, like Artificial Intelligence (AI), machine learning, and sophisticated sensors to navigate and make decisions independently, making them capable of avoiding hazards and responding to changing conditions. 

The key technologies used are: Artificial intelligence (AI) algorithms, machine learning, sensors, and navigation systems. Artificial intelligence (AI) algorithms are used to analyze data, make decisions, and control the aircraft’s systems. Machine learning allows the aircraft to learn from incoming data and improve its performance over time. Multiple sensors are used, such as cameras, radar, and lidar, to provide the aircraft with a view of its surrounding environment enabling it to navigate safely. Lastly, advanced navigation systems, including the Global Positioning System (GPS) and other sensors, are used to determine the aircraft’s position and guide it along its planned route.

Classification of autonomous air vehicles

Autonomous aircraft comprise a set of technologies to partially or entirely replace the human pilot in navigating an air vehicle, while avoiding airborne hazards and responding to traffic conditions.

Currently, there is no international standard for determining the level of automation of Unmanned Aircraft Systems (UAS) (i.e., autonomous air vehicles). The European Cockpit Association has, however, tried to provide a potential classification list with six stages of automation in air vehicles going from 0-5. In the automation-level 0-3 there must be a ‘pilot-in-command’ with traditional piloting-skills, whereas in automation-level 4-5 there is no requirements for a pilot-in-command but there must be a ‘Mission-commander’ with appropriate skills and competencies.

At all levels, a human is to retain command, meaning that a pilot has or is exercising direct authority, however, the pilot does not necessarily directly control the aircraft. From level 0-3, the pilot is the fallback option in the event of failures or issues. The pilot is, therefore, still required to have a pilot license and is referred to as the ‘Pilot-in-Command’ by the European Cockpit Association. In contrast, there is no requirement for a pilot-in-command in the automation-level 4-5. Here, the authority of the pilot is limited to the parameters of the mission to be flown, such as technical, regulatory, or legal considerations. This type of role within the aircraft is referred to as the ‘Mission-commander’ by the European Cockpit Association.

The ultimate difference between the automation-level 4 and 5 is within the Operational Design Domain (ODD). The Operational Design Domain (ODD) defines the specific conditions under which an automated driving system (ADS) or feature is designed to operate safely. It essentially outlines the "where" and "when" of an autonomous vehicle's safe operation, encompassing factors like road type, weather, time of day, and other relevant environmental and operational parameters. In the automation-level 4, the operational design domain (ODD) is limited, consequently requiring the Mission-commander to have sufficient knowledge regarding these limitations in order to be able to understand and execute their command authority. The operational design domain (ODD) limitations include things such as background knowledge on navigation, flight performance, and aviation law. The Mission-commander at level 4, thus, must have airmanship skills (i.e., encompass the knowledge, skills, and attitude required for safe and proficient aircraft operations).

In the last automation-level, stage 5, the aircraft operates fully autonomously. This means that the operational design domain (ODD) becomes unlimited, and the Mission-commander may no longer require any aviation knowledge or skills to execute their command authority. The European Cockpit Association explains, that in a highly automated system, the ‘command-authority’ could simply be to turn the aircraft on or off. However, the association do go on to furtherly explain that the Mission-commander is required to be sufficiently informed about the implications of the decision. This includes any consequences and liabilities.

The functionality and sufficiency of an aircraft, regardless of whether the air vehicle is partially or fully automated, depend on the well-functioning of satellites (i.e., critical space infrastructure). As explained earlier, autonomous transportation systems rely on a vast array of technologies which are all dependent on the data exchange process between satellites and receivers. This furtherly implies a dependency on the conditions of the activities happening on the Sun.

The foundational elements of fully autonomous air vehicle systems are machine learning and artificial intelligence (AI). Yet, these depend on and are enabled by satellites. Machine learning is used to train aircraft to learn from the complex data that they receive to improve the algorithms that they operate under, and to expand their ability to navigate in air. They, thus, rely on the data transmission and exchange capabilities enabled by for example satellites providing 5G networks. Artificial intelligence (AI) enables the aircraft’ systems to make instant operational decisions without needing specific instructions for each potential situation encountered while flying. It uses connected vehicle technology to communicate with other aircraft and infrastructure in order to detect close-by objects and map its surrounding environment.

Powerful computer systems process the collected data, wherefrom discissions about vehicle operations are made, continuously adjusting things such as steering. This is all done through a continuous communication between the aircraft’s sensors constantly collecting information about its surroundings and sending it back to its computer system, wherefrom it is processed and decisions are made. This computer system is operated by artificial intelligence (AI) that continuously depend and runs on services provided by satellites. Furthermore, the entire vehicle system depends on the 5G network for quick response and communication between the vehicles’ systems. Thus, the aircraft depend on telecommunication satellite services and the Global Navigation Satellite System (GNSS).

The aviation industry is becoming more aware of the impact of space weather on flight operations due to the increase of cross-polar traffic. Currently, the primary concern is the risks during high-latitude (>50°N) and polar operations (>78°N), due to the South Atlantic Anomaly (SAA). However, with a goal of creating fully autonomous aircraft for multiple services, it demands more research and communication between industry and academia, and establishments specialized in space weather and Disaster Risk Reduction (DRR) and resilience.

Image Credit: Global Aerospace: C2 Link System (simplified schematic).C2 links are essential in drone operations where the aircraft is being remotely piloted by a human or is programmed to fly autonomously.

Services enabled by autonomous air vehicles

While fully autonomous commercial airliners may still be some years away, the technology is rapidly advancing in other areas like private jets, cargo delivery, and urban air mobility. 

Autonomous aircraft are used for numerous purposes. They are being developed for cargo transportation to revolutionize logistics and delivery services (e.g., drones), and for military purposes for things such as surveillance, reconnaissance, and combat. Additionally, future goals are to enable: 1) Urban air mobility (UAM), providing autonomous air taxis; 2) Electrically powered vertical take-off and landing aircraft (i.e., ‘eVTOL’ (vertical take-off and landing)) for urban transportation to reduce traffic congestion and commute times, and; 3) Private jets, potentially offering increased efficiency and convenience.

Furthermore, autonomous aircraft are also being used for various other tasks, including aerial photography, agricultural applications, and infrastructure inspection.

Benefits of autonomous air vehicles

The benefits of autonomous aircraft are generally assumed to be enhanced safety due to its ability to process a vast amount of data, enabling it to make quick and precise decisions in emergency situations, and increased efficiency due to its ability to optimize flight paths, consequently reducing fuel consumption and streamline operations. Additionally, it can potentially reduce operating costs, making air travel more affordable, and increase accessibility to people living in remote areas and reduce congestion in urban centers.

Risks and vulnerabilities

Before these advanced air vehicles are made and fully integrated into society, the industry has to consider the challenges and the associated risks and vulnerabilities created with the implementation of autonomous aircraft. Some of these are ensuring the safety and reliability of autonomous systems and the protection of autonomous aircraft from cyberattacks.

Autonomous transportation systems rely on a vast array of technologies, such as satellites and receivers enabling navigation, cellular networks for communication, and onboard functioning computers. It is these technologies that enables the autonomation of transportation systems.

Space weather impact on modern aircraft is to some extent known, and, due to the increased air traffic around the polar routes and the experienced financial losses caused by space weather, this natural hazard is recognized within the aviation industry. Yet, this does not apply to the autonomous transportation systems. The effects and the potential disruption caused on the autonomous transportation systems that the autonomous air vehicles would rely on are currently still not well known. In order to obtain the safety certification of autonomous aircraft, the industry has to acknowledge the risks and vulnerabilities associated with space weather impact on the whole system of autonomous air vehicles.

Source

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