Scope 1.1 This specification provides a process for performing system level verification of aircraft systems and equipment. It provides a means of compliance that can be used for systems and equipment with software and Airborne Electronic Hardware (AEH) that have not been addressed by traditional development assurance methods. 1.2 This process can be used to show compliance to regulations that require a demonstration that functionality was implemented as intended, including safety mitigations that address failure conditions for software and AEH aspects for aircraft systems and equipment. 1.3 While this specification was developed with systems and equipment installed on aircraft certification level 1 and 2 (or class I and II in accordance with Advisory Circular (AC) 23.1309-1) normal category aeroplanes in mind, the content may be more broadly applicable. It is the responsibility of the Applicant to substantiate broader applicability as a specific means of compliance and obtain concurrence for its use from the applicable Civil Aviation Authority (CAA). 1.4 When using this specification, regulations that govern system safety requirements applicable to the aircraft still apply. In complying with those regulations, additional architectural mitigations such as redundancy, independence, separation, system monitors, etc., may be required in addition to the verification process specified in this specification. 1.5 The system level verification activities expected by this specification increase as the severity of the failure conditions applicable to or affected by the function increase. Those functions, which have hazardous and catastrophic failure conditions, receive additional activities through this process to provide detailed scrutiny. For normal category aircraft, refer to Practice F3309, Practice F3230, or AC 23.1309-1 for more information on the identification and classification of system failure conditions. Involvement of the applicable CAA personnel or their designees in this system verification process should be discussed early in the project. 1.6 This verification process specifically addresses definition, identification, and verification of system functions. Processes conducted under this specification may not satisfy all applicable external requirements; additional review on the part of the system developer, integrator, or installer may be required to meet specific requirements or the specified mission of the aircraft, or both. 1.7 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard. 1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
