20-115C - Airborne Software Assurance

Date Issued
July 19, 2013
Responsible Office
AIR-120,  Aviation Safety - Aircraft Certification Service, Aircraft Engineering Division

a. This AC describes an acceptable means, but not the only means, for showing compliance with the applicable airworthiness regulations for the software aspects of airborne systems and equipment certification. This AC is not mandatory and is not a regulation. Other ACs may describe alternate means.

b. We, the Federal Aviation Administration (FAA), wrote this AC to recognize the following RTCA, Inc. documents (RTCA DO):

 (1) RTCA DO-178C, Software Considerations in Airborne Systems and Equipment Certification, dated December 13, 2011.

(2) RTCA DO-330, Software Tool Qualification Considerations, dated December 13, 2011.

(3) RTCA DO-331, Model-Based Development and Verification Supplement to DO­178C and DO-278A, dated December 13, 2011.

(4) RTCA DO-332, Object-Oriented Technology and Related Techniques Supplement to DO-178C and DO-278A, dated December 13, 2011.

(5) RTCA DO-333, Formal Methods Supplement to DO-178C and DO-278A, dated December 13, 2011.

Note: RTCA DO is hereafter referred to as DO.

c. References to use of DO-178C in this AC include use of supplements and DO-330 as applicable.

d. This AC also establishes guidance for transitioning to DO-178C when making modifications to software previously approved using DO-178, DO-178A, or DO-178B.

07/19/2013 AC 20-115C


e. This AC also explains the use of DO-178C for Technical Standard Order (TSO) authorizations.

f. This AC does not obligate the FAA to approve any data or perform any activities as specified within the referenced RTCA documents.


g. If you use the means in this AC as a means of compliance, you must follow it entirely.