Reviewing these documents will permit the PO a look at how the program is progressing long before the first software build. 

## 5.3 Approval Authority 

The approval authority is responsible for approving the safety aspects of the project by leveraging the work done by the applicant. The approval authority does not approve only the software, but the entire system, which includes software, hardware, procedures, and processes. To address the safety requirements related to software development assurance, the approval authority must: 

• Review and approve the PSP to ensure that the proposed processes will be sufficient for generating evidence of compliance with RTCA DO-278A, 

• Review the evidence of compliance submitted by the applicant, 

• Perform audits on the project, and 

• Make a finding of compliance with evidence supporting that the RTCA DO-278A standard has been followed. 

The approval authority does not review the entire project; they only spot check the evidence to ensure the applicant is fulfilling their responsibilities. It is possible for the approval authority to make a finding of compliance to a program that is not fully compliant. Only the applicant has the visibility and responsibility to ensure the developer’s compliance. 

The ATO Chief Safety Engineer, as the safety approval authority, allows the PO to review all RTCA DO-278A (or equivalent) deliverables and submit evidence of their compliance reviews. The ATO Chief Safety Engineer will base his/her approval on the evidence of compliance presented and will, as needed, ask to see specific documents as part of the evaluation. The PSP must document the details of this relationship. 

## 6 Software Review Process 

The software review process is the vehicle for establishing communication and understanding between the applicant and the approval authority. The review process includes inspection and examination of the software lifecycle data, software project progress and records, and other evidence to assess compliance with RTCA DO-278A objectives. This process may consist of a combination of reading documents, interviewing project personnel, witnessing activities, sampling data, and participating in briefings. RTCA DO-278A, Section 10, states that the approval authority may review the software lifecycle processes and data to assess compliance with RTCA DO-278A. This appendix does not change the intent of RTCA DO-278A but clarifies its application. 

## 6.1 Objectives of the Software Review Process 

The approval authority may review the software lifecycle processes and associated data at his or her discretion to confirm that a software product complies with the approval basis and the objectives of RTCA DO-278A. The software review process assists both the approval authority and the applicant in determining whether a project will meet the approval requirements and RTCA DO-278A objectives by providing: 

• Timely technical interpretation of the approval basis, RTCA DO-278A objectives, approval authority policy, issue papers, and other applicable approval requirements; 

