Special Condition: Bell Helicopter Textron Canada Limited Model 429 Helicopters, High Intensity Radiated Fields

This special condition is issued for the Bell Helicopter Model 429 helicopters. These helicopters will have novel or unusual design features associated with installing electrical and electronic systems that perform critical functions, including an Electronic Flight Instrument System (EFIS) and a Full Authority Digital Engine Control (FADEC). The applicable airworthiness regulations do not contain adequate or appropriate safety standards to protect systems that perform critical control functions, or provide critical displays, from the effects of high-intensity radiated fields (HIRF). This special condition contains the additional safety standards that the Administrator considers necessary to ensure that critical functions of systems will be maintained when exposed to HIRF.