The U.S. Army’s Common Avionics Architecture System (CAAS) Product Line: A Case Study

This report is one in a series of Carnegie Mellon Software Engineering Institute case studies of organizations that have adopted a software product line approach for developing a family of software-intensive systems. The U.S. Army's Technical Applications Program Office (TAPO) has adopted a product line approach for the avionics software used for the Army's special operations helicopters. That software is based on Rockwell Collins' Common Avionics Architecture System (CAAS). The product line has evolved beyond its original scope and is now being adopted to include other Army aviation platforms such as cargo and utility helicopters. This case study describes the acquisition context and organizations involved in the product line, the history behind the development and evolution of the product line, its application to the mission of the Army's special operations helicopters, the Army's motivation for adopting a product line, specifics of the product line approach, and the underlying CAAS system and software architecture. The case study also highlights the software product line accomplishments, examines the results and lessons learned from TAPO's and Rockwell Collins' perspective, and discusses future considerations.