Special Conditions: Cessna Aircraft Company Model 500, 550, S550, and 560 Series Airplanes; High-Intensity Radiated Fields (HIRF)

These special conditions are issued for Cessna Aircraft Company Model 500, 550, S550, and 560 series airplanes modified by ElectroSonics. These modified airplanes will have a novel or unusual design feature associated with the installation of new dual air data display unit systems that perform 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.