The software development process encounters several challenges due to the increasingly functional, complex, expensive, and condensed development cycles of civil aircraft avionics systems, including inaccurate requirements, overly coupled architecture design, and difficult tracing process outputs. We propose a solution to the difficult software development issues for civil aircraft avionics systems based on research into digital development, process development, continuous integration, cloud development environments, and other cutting-edge technologies and methods. The research paper demonstrates how the solution for civil aviation software development is used in the process of developing avionics systems software. The findings demonstrate the viability of the complex avionics system software development and management method for civil aircraft proposed in this paper. To increase the effectiveness and caliber of software development, the method has been used in the development of the C919 civil aircraft display system.