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The temperature rise on the rear side of protected carbon fiber composite (CFC) panels caused by lightning continuing currents was determined. Painted CFC-panels with a thickness of 1, 2 and 3 mm were tested. Rectangular currents with an amplitude of 400 A and 800 A were used. The duration of the currents was varied from 20 ms to 50 ms representing the typical dwell time expected for zone 2A. Additional experiments with an exponential decaying current were carried out for comparison purposes. The temperature on the rear side of the panels was determined with a thermograph based on an infrared (IR) camera system. Arc movement and delamination at the arc root was observed with a high speed camera.

The flashover voltage characteristics of different types of segmented diverter strips were determined. Especially the resistive layer on the rear side of the strip, which protect the strip from electrostatic discharges, has a major influence on the flashover characteristics. The voltage waveform A defined in many aircraft standards with a voltage steepness of 1000 kV/μs ± 50% does not lead to the highest flashover voltages. With a lower voltage steepness, typically between 1 and 10 kV/μs, the flash-over voltages can increase by a factor of four. Analytical investigations can give explanations for this behaviour. The voltage distribution along the segmented diverter strips changes from a capacitive controlled voltage distribution to a resistive controlled voltage distribution when reducing the voltage steepness.