New Methodology for Determining the Extension of Lightning Swept Stroke Zones on Airborne Vehicles

During the lightning strike to an aircraft in flight, the lightning channel gets deformed in the aerodynamic flow and displaced along the aircraft, a so-called swept stroke. To be able to correctly determine the different levels of hazards on an aircraft (zoning), the physical behaviour of the lightning swept stroke must be understood. This behavour is outlined in the paper and a model for numerical simulations of the swept stroke process is presented together with examples of 3D simulations. The overall objective to include this model within the frame of an operational code for zoning computations is discussed in conclusion.