Special Conditions: Boeing Model 747-2G4B Series Airplanes; High-Intensity Radiated Fields (HIRF)

These special conditions are issued for Boeing Model 747-2G4B series airplanes modified by Boeing Airplane Services. These modified airplanes will have novel or unusual design features when compared to the state of technology envisioned in the airworthiness standards for transport category airplanes. The modification incorporates the installation of new Electronic Flight Instrument System (EFIS) displays. The EFIS displays will utilize electrical and electronic 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.