The SAE, at the request of the FAA, established the AE4R Subcommittee for the purpose of evaluating the hazard to airborne electronic systems produced by the electromagnetic environment.This task involves determining the intensity of the electromagnetic environment, proper design procedures, and the establishment of test techniques. The task of panel one, the data accuracy panel, is to determine the level of the electromagnetic environment to which an aircraft could be exposed. A list of detailed assumptions was produced. These assumptions were applied to the known emitter population. Then, a set of histograms was derived which depicts the electromagnetic environment that an aircraft may experience under various conditions of operation.