Before revision: The Advisory Circular AC 20-152 , Design Assurance Guidance for Airborne Electronic Hardware, identifies the RTCA-published standard DO-254 as defining "an acceptable means, but not the only means" to secure FAA approval of complex custom micro-coded components within aircraft systems with Item Design Assurance Levels (IDAL) of A, B, or C.AC 20-152, FAA, Office AIR-100, 2007.
After revision: The Advisory Circular AC 20-152a , Design Assurance Guidance for Airborne Electronic Hardware, identifies the RTCA-published standard DO-254 as defining "an acceptable means, but not the only means" to secure FAA approval of complex custom micro-coded components within aircraft systems with Item Design Assurance Levels (IDAL) of A, B, or C.AC 20-152, FAA, Office AIR-100, 2007.