Are you working in an aeronautical engineering area? From my limited knowledge of practices at Boeing and Airbus industries, your post suggests are lack of compliant design and documentation in terms of the many international standards for avionics and related equipment.
My experience is in fields of instrumentation and control for electrical power generation and transmission, and steelworks automation. The projects I have worked on use IEEE SWEBOK and OMG SYSML as a minimum. The management have traditional engineering background (mechanical, electrical, civil and chemical) so design documentation is extensive and then updated to "as built" status when commissioned. Generally we create models and perform extensive validation and scenario testing before committing to production code.
My experience is in fields of instrumentation and control for electrical power generation and transmission, and steelworks automation. The projects I have worked on use IEEE SWEBOK and OMG SYSML as a minimum. The management have traditional engineering background (mechanical, electrical, civil and chemical) so design documentation is extensive and then updated to "as built" status when commissioned. Generally we create models and perform extensive validation and scenario testing before committing to production code.