As the functional and nonfunctional requirements of defence systems become more complex and precise, concerning about the systematic development of software embedded into the defence systems has become surged up. In order to develop more reliable and correct software, and to extend the life cycle of the developing software, adoption of some engineering technologies such as development process, methodology, CASE tools and documentation is essentially required. This paper introduce an approach to technical information management in embedded software development process, with an instance, airborne ECM system development project. Particularly, we suggest and explain how to guide the software development according to process and methodology, and how to generate technical documents using CASE tool.