Wire bundle currents for High Intensity Radiated Fields (HIRF) and Indirect Effects of Lightning (IEL) with focus on Bulk Current Injection (BCI) test

The operating environment of aircraft is characterised by relevant Radio Frequency (RF)-fields. The potential RF exposure of aircraft is commonly called the High Intensity Radiated Fields (HIRF) environment. Aircraft functionality in the HIRF environment is a necessity to reach certification. One effect when operating in the HIRF environment are RF cable bundle and wire currents inside the aircraft. Prior to installation of avionics inside an aircraft this potential threat is tested on equipment and system level via the Bulk Current Injection (BCI) technique. The BCI technique is a substitution method. The conducted injection is used to generate the RF currents on the cable bundles and wires directly. The development of the BCI technique and associated test levels over the last years are discussed in the present paper. In particular the RF current generated with the BCI technique is compared to the one during RF field exposure. A comparison to results for Indirect Effects of Lightning (IEL) is provided.