Sources of Weapon System Cost Growth: Analysis of 35 Major Defense Acquisition Programs

Abstract : Previous RAND Project AIR FORCE work has concluded that the Department of Defense (DoD) and the military departments historically have underestimated the cost of new weapon systems. Analysis of the data in Selected Acquisition Reports (SARs) for a sample of 68 completed programs showed that the average total cost growth (after adjusting for procurement-quantity changes) was 46 percent over the baseline estimate made at Milestone B (MS B) and 16 percent over the baseline estimate made at MS C. The cost growth typically continued for about 75 percent of the time between the initiation of major development and the expending of 90 percent of program funding. Most of the cost growth occurred early in the acquisition phase, and the magnitude of development cost growth at completion for programs initiated in the 1970s, 1980s, and 1990s remained relatively steady. Although quantifying cost growth is important, the larger issue is why cost growth occurs. To answer that question, this analysis examines 35 mature, but not necessarily complete, major defense acquisition programs (MDAPs) from the database of SARs that document the development and procurement of a variety of systems, including aircraft, missiles, electronics systems, launch vehicles, munitions, vehicles, and satellites. The programs were similar in type and complexity to those conducted by the Air Force. We analyzed a relatively small number of programs because of the labor-intensive nature of the work. We first examined the programs as a complete set and then analyzed Air Force and non Air Force programs separately to determine whether the causes of cost growth in the two groups differed.