Safety and Security Considerations on the Airbus Wake Energy Retrieval Program "fello'fly"

Faced with climate change and global warming, the reduction of greenhouse gas emissions, such as carbon dioxide, is a modern day focus of politics, industry and society. The aviation industry, responsible for about 3.5% of worldwide greenhouse gas emissions, is currently heavily depending on fossil fuels. As such, efforts are made to move towards a sustainable green aviation and carbon neutrality. Projects undertaken by authorities, airlines or manufacturers vary from new technologies like electric propulsion or Sustainable Aviation Fuel (SAF), to adjustments of operating procedures such as the retrieval of wake energy. [22] One already tested Wake Energy Retrieval (WER) technology is Airbus' fello'fly project.Hereby, different aircraft are positioned closely together on intercontinental flights, such that the succeeding aircraft can benefit from upward air movement within the wake created by the preceding one. Flight trials conducted in 2021 have shown a significant opportunity to reduce fuel consumption and therefore the carbon dioxide emissions and costs on long-range flights. However, to benefit from wake energy requires a reduction in currently established safety distances between aircraft. As introduction into service is envisioned as early as 2025, the fello'fly system will be based on already existing technologies.This paper focuses on possible safety and security implications created by this combination of reduced safety distances and reliance on legacy communication, navigation and surveillance technologies. First, regulations governing aircraft separation will be introduced, followed by an introduction to the concept of fello'fly. Furthermore, the paper offers an overview of the employed technologies and underscores their known cybersecurity vulnerabilities. The implications of using these systems alongside reduced separation in an evolving threat landscape are examined. The paper concludes by proposing necessary enhancements for a secure implementation of wake energy retrieval.