C H A P T E R
N ° 34
Autonomous Aircraft and Mitigation Measures
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 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 ° 27-33, 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 fourth, and last, 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: Natilus.
Mitigation measures
The significant difference between space weather impact on modern aircraft and future autonomous air vehicles can be found in the mitigation strategies.
To mitigate space weather impact on current modern aircraft, airlines traditionally make measures such as canceling flights, lowering altitudes, or rerouting, at the cost of more fuel consumption or economic losses. This is mostly during enhanced radiation exposure risks, especially to aircrews. Similar mitigation strategies can be utilized for autonomous air vehicles.
However, the current mitigation measures used in modern aircraft may not be adequate enough. Certain strategies can simply not be utilized, whereas others provide a certain level of risk when utilized.
Navigation and the Global Navigation Satellite System (GNSS)
When satellite navigation systems are compromised, there are alternative ways for modern aircraft to navigate in air. Although satellite navigation services like the Global Positioning System (GPS) and Galileo make a significant difference for flight operations, pilots do currently not rely on this service. Alternative ground-based navigation systems like Very High-Frequency Omnidirectional Range (VOR), Distance Measuring Equipment (DME), and Non-Directional Beacon (NDB) can be utilized in case of satellite navigation system failures.
* A Very High Frequency Omnidirectional Range (VOR) is a type of short-range radio navigation system for aircraft that uses Very High Frequency radio waves to transmit signals allowing pilots to determine their bearing (i.e., direction) relative to a ground station. It is widely used in aviation for en-route navigation and non-precision approaches to runways. *
* Distance Measuring Equipment (DME) is a radio navigation technology used in aviation to determine the distance between an aircraft and a ground-based transponder station. It is often paired with Very High Frequency Omnidirectional Range (VOR) systems, enhancing navigation accuracy. *
* A Non-Directional Beacon (NDB) is a low or medium frequency radio transmitter used as a navigational aid for aircraft. It emits signals in all directions, allowing pilots to determine their bearing (i.e., direction) relative to the beacon (a light or radio transmitter used as a navigational aid or to indicate the presence of an airport or other important location) using an Automatic Direction Finder (ADF). It is often used for en-route navigation, instrument approaches, and as a backup for other navigation systems. *
However, using these systems could potentially reduce airspace capacity and cause imbalances between flight demand and airport capacity. Additionally, these back-up systems are expensive to maintain.
If a ground station lacks navigation capabilities in a case of autonomous air vehicles, it would be unable to guide an autonomous aircraft using traditional methods like the Global Positioning System (GPS) or other satellite-based navigation systems, consequently leading to several issues:
First, without accurate navigation data, the autonomous aircraft’s operational range and coverage aera would be significantly restricted. Ground stations rely on precise location data to guide the aircraft, and without it, they cannot effectively manage the aircraft's flight path. This is especially over longer distances. Thus, a lack of accurate navigation would limit the aircraft’s range and coverage.
In a case where there is no space weather event occurring, autonomous aircraft could use alternative navigation systems to determine their position and orientation. This could, however, cause limitations in accuracy, reliability, and the type of environments where the aircraft can operate. Yet, in cases of a space weather event occurring, autonomous air vehicles could be unable to fly, due to the high risks of data inaccuracies and complete or partial loss of situational awareness with the aircraft.
Without accurate navigation, the risk of collisions with obstacles, terrain, or other aircraft increases. In the absence of precise positioning information, the aircraft's autonomous flight control systems may struggle to make safe decisions, potentially leading to accidents. A loss of navigation capabilities, thus, increase the risk of accidents.
Secondly, managing multiple autonomous aircraft from a ground station lacking navigation capabilities would be incredibly complex. The ground station operator would need to rely on other means of tracking the aircraft's position, such as visual observation, external tracking systems or using multi-sensor fusion combining data from multiple sensors (e.g., camera and Lidar). Yet, any system compromised during a space weather event has the risk of providing inaccurate data and, thus, inaccurate information.
Lastly, autonomous aircraft could be limited to simpler missions with shorter flight times and lower payloads due to the challenges of navigating without precise position information. However, this is in a case of a compromise of only the navigation capabilities.
While autonomous aircraft can operate without a traditional ground station, doing so presents significant challenges and limitations. The absence of navigation capabilities at the ground station would require reliance on alternative navigation systems, potentially impacting range, accuracy, safety, and mission capabilities.
Communication delays and failures
A lack of communication capabilities in traditional modern aviation involves proactive measures and procedures to maintain situational awareness and safety during communication outages. This includes the use of backup communication methods, ensuring proper transponder settings, and adhering to established procedures for managing loss of communication scenarios.
However, the same does not apply for fully autonomous aircraft. Autonomous aircraft rely on real-time data exchange with ground control for tasks like navigation, obstacle avoidance, and emergency response. Delays or complete communication blackouts can lead to incorrect decisions, potentially causing accidents or system malfunctions. Whereas a pilot can navigate using established procedures when experiencing a loss of communication within modern aircraft, this will not necessarily be the case for autonomous vehicles.
Autonomous vehicles may only be provided with a button to start and turn-off the engines of the aircraft. In a case like this, no one onboard the aircraft would be able to manually control it out of safety risks. If this will be the future design of autonomous aircraft, a loss of communication with such air vehicles would seriously increase the risk of catastrophes from occurring.
Situational Awareness
In aviation, situational awareness refers to a pilot's understanding of the factors and conditions affecting the flight, encompassing the aircraft, environment, and other relevant elements, allowing for informed decision-making and proactive responses. It is not limited to only knowing about what is currently happening, but also anticipating what might happen next.
In autonomous aircraft, situational awareness refers to the system's ability to perceive its environment, understand the meaning of its observations, and project future states, enabling safe and effective operation. It is the equivalent of a human pilot's understanding of the aircraft's position, surrounding airspace, potential hazards, and the overall flight situation. Essentially, the autonomous system needs to know ‘what is happening’ and ‘what is likely to happen’ to make appropriate decisions.
The possible capability of obtaining situational awareness differs between modern and fully autonomous air vehicles due to the human component. In modern aircraft, pilots can take over when certain systems are failing. A mitigation strategy that can be utilized is, therefore, operating manually. Yet, this is not the case of fully autonomous aircraft. In this case, the safety regarding situational awareness capabilities of autonomous air vehicles is, therefore, easier compromised during space weather events.
Sensors and Control System failures
In air vehicles, sensor and control system failures can significantly impact flight safety and performance. Sensor and control system failures in modern and autonomous aircraft are mitigated similarly through a combination of redundancy, fault detection, and robust control strategies.
Redundancy involves using multiple sensors and control systems to perform the same function, so that if one fails, others can take over. Fault detection systems identify when a sensor or system is malfunctioning, and robust control algorithms can compensate for these failures, ensuring the aircraft continues to operate safely.
Mitigation measures to explore
Mitigation measures for fully autonomous air vehicles are extremely complex. Although there will always be a level of risk with anything, the risks associated with autonomous aircraft are many and concerning. This is especially in regards to space weather and its interaction with the aviation industry and the critical infrastructures that it depends on. In order to enable a certain level of resilience from space weather impact on autonomous air vehicles, the following areas could be explored:
Space weather monitoring and improved space weather forecasting: Implementing real-time monitoring of space weather conditions and providing accurate space weather forecasts to aviation operators. Enhanced space weather forecasting and prediction capabilities are crucial for providing timely warnings to the aviation industry, allowing for proactive measures to be taken. In the future, these mitigation measure have to be much more advanced and quicker in order to reduce the risks and vulnerabilities associated with the use of fully autonomous aircraft. However, it is important to acknowledge that space weather forecast and warning systems is only one mitigation strategy and should be used in combination with a long list of other mitigation measures. Thus, it should be a part of the mitigation strategy rather than being the only implemented mitigation measure against space weather.
Enhanced system redundancy and resilient system design: Building redundancy into autonomous systems and incorporating fail-safe mechanisms can help mitigate the impact of space weather events. It is a crucial strategy to mitigate the impacts of space weather on the aviation industry and, generally all critical infrastructure and technologies. This involves implementing backup systems or alternative pathways to ensure continued operation during disruptions caused by space weather. Redundancy can be achieved through various methods, including using multiple Global Navigation Satellite System (GNSS) constellations, integrating internal sensors that measure acceleration and rotation, which is crucial for satellite navigation and stabilization, and employing shielding and hardening techniques for electronic components. Using redundant systems for critical functions can ensure functionality in case of space weather-related disruptions.
Radiation shielding: Implementing radiation shielding measures on autonomous aircraft is crucial in order to protect onboard electronics and aircrew from excessive radiation exposure.
Advanced monitoring systems: Developing and implementing advanced monitoring systems, such as those that integrate Automatic Dependent Surveillance-Broadcast (ADS-B) data with space weather information, can improve situational awareness and enable more precise space weather predictions.
Collaboration and Research: Continued collaboration between scientists, engineers, the disaster risk reduction and resilience community, and the aviation industry is essential for developing mitigation strategies to address the challenges posed by space weather, and to ensure the safe and reliable operation of autonomous aircraft.
Future Outlook
Image Credit: Freethink; Droneliner.
Overall, understanding and mitigating the impact of space weather on autonomous aircraft is crucial for ensuring the safe and reliable operation of these increasingly important technologies.
Autonomous aircraft are expected to play an increasingly significant role in the future of aviation. While fully autonomous commercial airliners may still be some years away, advancements in autonomy are expected to continue in other areas of aviation. The development of autonomous aircraft is likely to be an incremental process, with increasing levels of autonomy being introduced over time. It is important that during the research and development process of these future air vehicles, space weather mitigation measures are incorporated.
The risk of incorrect information or a temporary blackout of communication increases safety risks for the passengers onboard the autonomous aircraft and their surroundings. The interaction and potential effects of space weather on autonomous air vehicles, therefore, must be taken into account when creating such advanced inventions.
An aircraft like a fully ‘self-flying’/autonomous aircraft depending on satellite services is more vulnerable to the effects of space weather impact compared to current non or partially autonomous air vehicles. This means, that the risk of an emergency or disaster occurring caused by space weather is higher for fully autonomous air vehicles. This is because the main difference in space weather impact on modern vs. autonomous aircraft is the human component.
As soon as a human-being cannot control something manually, the risks of the effects caused by space weather increases, which furtherly increases the risk of emergencies and potential disasters. The current and future changes in the aviation industry’s way of designing and constructing air vehicles will, therefore, determine the overall level of risk and vulnerabilities posed on future air vehicles and their passengers – not to mention terrestrial infrastructure and people on ground - when discussing space weather impact.
Current knowledge on the relation between space weather and autonomous air vehicles is sparse. Moreover, current mitigation measures for space weather impact on the aviation industry in general is limited. The need for research and development of space weather impact on the aviation industry and novel mitigation measures, therefore, remains.
Source
European Cockpit Association (ECA) Piloting Safety (2020): “Unmanned aircraft systems and the concepts of automation and autonomy”. ECA Briefing Paper. https://www.eurocockpit.eu/positions-publications/unmanned-aircraft-systems-and-concepts-automation-and-autonomy
ESA (2012): “ESA safety information bulletin”. ESA SIB No. 2012-09. https://skybrary.aero/sites/default/files/bookshelf/1803.pdf
ESA (2012): “ESA safety information bulletin”. ESA SIB No. 2012-10. https://skybrary.aero/sites/default/files/bookshelf/1802.pdf
ESA (2011): “Ionospheric delay”. https://gssc.esa.int/navipedia/index.php?title=Ionospheric_Delay
ESA (2011): “GNSS receivers general introduction”. https://gssc.esa.int/navipedia/index.php/GNSS_Receivers_General_Introduction
ESA (2011): “SBAS general introduction”. https://gssc.esa.int/navipedia/index.php?title=SBAS_General_Introduction
ESA (2011): “GBAS systems”. https://gssc.esa.int/navipedia/index.php?title=GBAS_Systems
ESA (2011): “WAAS general introduction”. https://gssc.esa.int/navipedia/index.php?title=WAAS_General_Introduction
ESA (2011): “Surveying, mapping and GIS applications”. https://gssc.esa.int/navipedia/index.php?title=Surveying,_Mapping_and_GIS_Applications
ICAO (2012): “Concept of operations (ConOps) for the provision of space weather information in support of international air navigation”. Draft versions 2.2. IAVWOPSG/7-WP/19. https://www2023.icao.int/safety/meteorology/iavwopsg/Space%20Weather/Forms/AllItems.aspx#InplviewHashe0eb8c3a-a779-477b-a928-9be9ad6fbfaf=SortField%3DTitle-SortDir%3DDesc
Royal Academy of Engineering (2013): “ Extreme space weather impacts on engineered systems and infrastructure”. ISBN 1-903496-95-0. https://www.raeng.org.uk/media/lz2fs5ql/space_weather_full_report_final.pdf
Global Aerospace (2024): ”The future of autonomous aircraft: insights from a leading authority”. https://www.global-aero.com/the-future-of-autonomous-aircraft-insights-from-a-leading-authority/
UK Civil Aviation Authority (2020): “Impacts of space weather on aviation”. https://www.caa.co.uk/publication/download/15787
Jones, J. B. L. et al. (2005): ”Space weather and commercial airlines”. ELSEVIER. Advances in Space Research. Vol. 36. Iss. 12. Pp. 2258-2267.
Erik, Schmölter et al. (2025): “Should we monitor space weather effects on surveillance technologies used in air traffic management? – First results”. AGU. Vol. 23, Iss. 4. DOI: https://doi.org/10.1029/2025SW004352
Xue, Dabin et al. (2024): “Space weather effects on trasportaiton systems: A review of current understanding and future outlook”. AGU. Vol. 22, Iss. 12. DOI: https://doi.org/10.1029/2024SW004055
Xue, Dabin et al. (2022): “Potential impact of GNSS positioning errors on the satellite-navigation-based air traffic management”. AGU. Vol. 20, Iss. 7. DOI: https://doi.org/10.1029/2022SW003144
NOAA (n.d.): ”Ionospheric scintillation”. https://www.swpc.noaa.gov/phenomena/ionospheric-scintillation
NASA (2024): ”Sun emits X6.3 flare on February 22, 2024”. Produced by Scott Wiessinger. https://svs.gsfc.nasa.gov/14535/
Ishii, Mamoru et al. (2024): ”Space weather impact on radio communication and navigaiton”. ELSEVIER. Advances in Space Research. DOI: https://doi.org/10.1016/j.asr.2024.01.043
Koops, L. (2017): “Cosmic radiation exposure of future hypersonic flight missions”. Radiation Protection Dosimetry. Vol. 175, Iss. 2, Pp. 267–278. DOI: https://doi.org/10.1093/rpd/ncw298
