Special Conditions: Gulfstream Aerospace Corporation Model G-1159B; High-Intensity Radiated Fields (HIRF)

These special conditions are issued for Gulfstream Aerospace Corporation Model G-1159B airplanes modified by ElectroSonics. These modified airplanes will have a novel or unusual design feature when compared to the state of technology envisioned in the airworthiness standards for transport category airplanes. The modification incorporates the installation of a Honeywell Dual Airdata Computer System that performs critical functions. The applicable airworthiness regulations do not contain adequate or appropriate safety standards for the protection of these systems from the effects of high-intensity- radiated fields (HIRF). These special conditions contain the additional safety standards that the Administrator considers necessary to establish a level of safety equivalent to that established by the existing airworthiness standards.