Reverse engineering & re-engineering of avionics legacy components

The average age of US military aircraft is 20+ years and the avionics systems on these aircraft are becoming increasingly more expensive to maintain and operate. Typically, the root of the problem can be traced to a few "bad actor" components within legacy avionics systems. These bad actor components are characterized by low reliability and high repair costs. The high repair costs are due to the age of the components (multiple past repairs make new repairs more difficult) and high cost or non-availability of replacement parts. These reliability and maintainability (R and M) problems lead to high and increasing cost of ownership. The objective of a re-engineering effort is to replace old technology components to "fix" a system level R and M problem to maximize life cycle cost savings for the remainder of the system life. Many times data is insufficient to re-engineer a system component without first reverse engineering the existing component. This paper details some reverse engineering and re-engineering techniques to replace low R and M legacy components. The reengineering of an A-10 armament control system is provided as an example of the process of developing a replacement system where data is not available for the existing system.