Numerical simulation of initial lightning attachment points on helicopter based on stream-leader discharge theory

The first step to the design of aircrafts is to determinate the initial lightning attachment points. In this paper, a fast numerical simulation method based on the stream-leader discharge theory is presented to simulate the initial lighting attachment point on the helicopter. Firstly, the size of the electrode, the distance between the helicopter and the boundary and other parameters are determined according to the test methods of the lightning attachment points in the SAE-ARP 5416A standard. Then, upward leader inception based on Beccera-Cooray criterion is used to analyze the tip of the main rotor and tail rotor , the head, and the horizontal tail of the UH-60 helicopter. Finally, finding the minimum electric field sustains the positive leader inception by continuously changing the potential of the electrode, which can provide basis to the analysis of the initial lightning attachment points. The simulation results show that the main rotor is most likely to be the lightning initial attachment point and the head is hard to be the lightning initial attachment point.