Methodology for determination of circuit safety margins for MIL-E-6051 EMC system test

The MIL-E-6051 electromagnetic compatibility (EMC) system test is concerned with the establishment of safety margins for avionics mission critical circuits. The safety margin (SM) of a circuit is the comparison of the circuit thereshold to the electromagnetic (EM) energy coupled into that circuit. In the case of the B-1B Avionics system certain difficulties were related to the complexity of the system with over 100 subsystem elements called line replaceable units (LRUs). A description is provided of the approaches taken and the analyses performed in selection of B-1B Avionics mission critical circuits to be sensitized or instrumented for test. Attention is given to aspects of methodology, mission critical LRU identification, interface circuit identification, circuit analysis, and wire-to-wire coupling analysis.