The guidance material in this document was developed in the context of Federal Aviation Regulations (FAR) and Joint Airworthiness Requirements (JAR) Part 25. It may be applicable to other regulations, such as Parts 23, 27, 29 and 33. In general, this material is also applicable to engine systems and related equipment. Final regulatory approval of all systems is assumed to be accomplished in conjunction with an aircraft certification.
This document has been prepared primarily fo relectronic systems which, by their nature, may be complex and are readily adaptable to high levels of integration. However, the guidance provided in this document may be considered for other aircraft systems.
This document addresses the total life cycle for systems that implement aircraft-level functions. It excludes specific coverage of detailed systems, software and hardware design processes beyond those of significance in establishing the safety of the implemented system. More detailed coverage of the software aspects of design are dealt with in RTCA document DO-178B and its EUROCAE counterpart, ED-12B. Coverage of complex hardware aspects of design are dealt with in RTCA document DO-xxx, (working title: "Design Assurance Guidance for Airborne Electronic Hardware,") currently under development by RTCA special Committee SC-180. Methodologies for safety assessment processes are outlined in ARP4761. Figure 1 outlines the relationships between the various documents which provide guidance for system development, safety assessment, and the hardware and software life-cycle processes.
This document is intended to be a guide for both the certification authorities and applicants for certification of highly-integrated or complex systems, particularly those with significant software elements. As such, the focus is toward ensuring that safety is adequately assured through the development process and substantiating the safety of the implemented system. Specific guidance on how to do the substantiation work is beyond the scope of this document, though references are provided where applicable.