The document discusses those aspects of airworthiness certification that pertain to the production of software for airborne systems and equipment used on aircraft or engines.

DO-178B Safety Levels

• Level A Catastrophic: prevents continued safe flight or landing, many fatal injuries
• Level B: Hazardous/Severe: potential fatal injuries to a small number of occupants
• Level C: Major: impairs crew efficiency, discomfort or possible injuries to occupants
• Level D: Minor: reduced aircraft safety margins, but well within crew capabilities
• Level E: No Effect: does not effect the safety of the aircraft at all

These relate to the criticality of the airborne system. Flight control, navigation, and all fly-by-wire systems are flight critical and require DO-178B Level A certification. Entertainment systems fall at the other end of the criticality spectrum and would be Level E systems (except for the crew’s ability to override it when making public announcements “PA”).

DO-178B Documentation Requirements

DO-178B requires a thorough definition and documentation of the software development process. The base set of required documentation and life cycle artifacts include:

• Plan for Software Aspects of Certification (PSAC)
• Software Quality Assurance Plan
• Software Configuration Management Plan
• Configuration Control Procedures
• Software Code Standard For Ada
• Software Design Standard
• Software Requirements Standard
• Software Development Plan
• Software Verification Plan
• Source, Executable Object Code, SCI and SECI
• Software Design Document
• Software Requirements Document
• Traceability
• Test Cases and Procedures
• Verification Results
• Quality Assurance Records
• Configuration Management Records
• Problem Reports
• Software Accomplishments Summary