Special Conditions; Premier Avionics Design Ltd., EFIS on the Cessna 441; Protection of Systems for High Intensity Radiated Fields (HIRF)

These special conditions are issued to Premier Avionics Design Ltd., 12002 Warfield, Suite 250, San Antonio, TX 78216, for a Supplemental Type Certificate for the Cessna 441 Conquest. This airplane will have novel and unusual design features when compared to the state of technology envisaged in the applicable airworthiness standards. These novel and unusual design features include the installation of an electronic flight instrument system (EFIS) in the form of two digital altimeters. The digital altimeters will be Thommen Model AD32E, one on the pilot side and one on the copilot side, for which the applicable regulations do not contain adequate or appropriate airworthiness 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 the airworthiness standards applicable to these airplanes.