DO-178B, Software Considerations in Airborne Systems and Equipment Certification is a guidance for software development published by RTCA, Incorporated. The standard was developed by RTCA and EUROCAE. The FAA accepts use of DO-178B as a means of certifying software in avionics.

The DO-178B guidelines specify:

• Objectives for software life-cycle processes.
• Description of activities and design considerations for achieving those objectives.
• Description of the evidence indicating that the objectives have been satisfied.

DO-178B defines five Development Assurance Levels:

• Level A: Catastrophic failure condition for the aircraft (e.g., aircraft crash).
• Level B: Hazardous/severe failure condition for the aircraft (e.g., several persons could be injured).
• Level C: Major failure condition for the aircraft (e.g., flight management system could be down, the pilot would have to do it manually).
• Level D: Minor failure condition for the aircraft (e.g., some pilot-ground communications could have to be done manually).
• Level E: No effect on aircraft operation or pilot workload (e.g., entertainment features may be down).