MotivationWith the rapid development of the low-altitude economy, increasing attention has been paid to the radiation environment safety of low-altitude aircraft such as drones and electric vertical take-off and landing (eVTOL) aircraft. Traditional views hold that the dense lower atmosphere is an effective barrier against cosmic radiation, but the shrinking feature sizes of modern integrated circuits (ICs) have significantly increased their susceptibility to single-event effects (SEEs). Most conventional studies have focused on the effects of particles such as neutrons and protons, while systematic evaluations of the risks induced by muons — the most abundant charged particles at sea level—remain scarce, particularly during extreme solar events. Therefore, this study quantitatively evaluates the muon-induced SEE risks of low-altitude aircraft in different regions of China under both static cosmic ray backgrounds and Ground Level Enhancements (GLEs), aiming to provide critical insights for the operational safety of next-generation low-altitude aviation platforms.

MethodsThis study employs city-specific atmospheric models and simulates atmospheric shower processes over different cities within the CORSIKA framework, yielding reliable energy spectra of low-energy muons (10–100 MeV) across diverse regions. Drawing on electrical simulation data from other research groups, this study estimates muon-induced SEE cross sections in transistors with different process nodes, covering Bulk, FD-SOI, and FinFET processes. Subsequently, by integrating solar energetic particle (SEP) energy spectra associated with Ground Level Enhancement (GLE) events, we evaluate muon-induced SEE risks for systems of varying sizes under both static conditions (only cosmic-ray injection) and GLE event scenarios.

ResultsOur results indicate that under static conditions, flight control systems (with 1 MB of memory) incorporating advanced process-node ( \leqslant 45 \;\mathrmnm) Bulk transistors are exposed to non-negligible muon-induced SEE risks across all cities in China. In contrast, systems utilizing FD-SOI transistors can effectively alleviate such risks. For systems with large memory capacities (1 GB), irrespective of the process technology employed, redundancy and other radiation-hardening measures must be adopted. Regarding GLE events, this study innovatively introduces the concept of muon hazard levels to evaluate regional variations in risk. Specifically, during GLEs, the aggravation of muon-induced SEE risks in mid-to-low latitude regions is negligible, whereas high-latitude regions experience a significant rise in such risk.