Hazards to Aircraft Crews, Passengers, and Equipment from Thunderstorm-Generated X-rays and Gamma-Rays

Both observational and theoretical research in the area of atmospheric high-energy physics since about 1980 has revealed that thunderstorms produce X-rays and gamma-rays into the MeV region by a number of mechanisms. While the nature of these mechanisms is still an area of active research, enough observational and theoretical data exists to permit an evaluation of hazards presented by ionizing radiation from thunderstorms to aircraft crew, passengers, and equipment. In this paper, we use data from existing studies to evaluate these hazards in a quantitative way. We find that hazards to humans are generally low, although with the possibility of an isolated rare incident giving rise to enough radiation dose to produce noticeable symptoms. On the other hand, unshielded computer memory chips in avionics systems stand a small but non-zero chance of severe damage from thunderstorm-generated radiation and would not leave easily detectable traces of the occurrence. Should a rare phenomenon called ball lightning occur near or within an aircraft, the possibility exists of substantial damage to both equipment and personnel. Overall, radiation hazards from thunderstorms appear to be low, but should be considered and investigated with radiation monitoring equipment on sample flights