Abstract : The purpose of this study was to estimate the costs and benefits of Pre-Planned Product Improvements (P3Is) to the Consolidated Automated Support System (CASS). CASS was designed in the late 1980s to early 1990s to eventually become the Navy's single tester for avionics, and is presently the most comprehensive general-purpose automatic test equipment in the Department of Defense. There is now interest in the Navy, OSD, and the Congress in further expanding the capability of CASS to test the new, emerging avionics systems, and also in applying CASS to Navy shipboard electronics, as well as electronics for the Marine Corps, Army, and Air Force. This study contributes to the improvement effort by constructing and analyzing a list of candidate P3Is that appear worthy of follow-on detailed engineering analysis. The costs of the improvements are estimated by the expenses of procuring the equipment (and supporting software), integrating the system into the CASS, and operating and supporting the new capability at operational sites. The benefits of the P3Is are estimated by their ability to test the emerging avionics systems that are being designed for new Navy and Air Force aircraft (F/A-18E/F, F-22, and A/F-X).