Computation of locations of possible stepped leader attachment points on an aircraft flying under thunderstorm conditions

Abstract

In case of flight in a thunderstorm region, a lightning strike on the aircraft might occur. For better lightning protection, the locations of points on the aircraft skin where a stepped leader can be attached should be delimited. In this paper, the areas of the skin of an aircraft where a stepped leader might be attached are defined through an approach based on the fact that electrostatics and potential flow theory have the same mathematical background. This is done by computing the distribution of the electrostatic field on the metallic parts of the skin of the aircraft due to the ambient electric field. In any area of the skin, where the electric field resulting from the combination of the ambient electric field and the local electric field can ionize the air, attachment points of a stepped leader might exist. The advantage of this approach is a decreased computational time and computer memory needed, as compared to a full Computational Physics approach. The areas of the skin of a generic airliner delimited through this approach, at least qualitatively, are in agreement with photos taken under real thunderstorm conditions.