Engine development entails about equal measures of performance testing and durability, or life testing. The differing requirements of these two types of testing have resulted in separate data acquisition systems. For performance work the system design reflects the needs for flexibility, accuracy, considerable calculation of data, and for the printing and plotting of results. For a durability facility, where the output is test hours instead of data, the data system design stresses test monitoring and control. This system has not yet gone on line, although a hand wired system has been in service for ten years.