This research examines Cost Growth Factors (CGF) at various program stages for 30 Department of Defense aircraft programs. From Milestone (MS) B, the authors determine CGFs at the Critical Design Review (CDR), First Flight (FF), Development Test and Evaluation End, Initial Operational Capability (IOC), and Full Operational Capability. They find development CGFs are significantly larger than procurement CGFs. Additionally, cost growth primarily occurs early in the program. At CDR, which occurs on average at the 12 percent completion point of a program, aircraft programs had already experienced on average 15 percent of their total program cost growth. The first spike in percent of total cost growth occurs at FF, 35 months or ~3 years after MS B. Lastly, the analysis shows that by IOC (approximately 6.5 years after MS B or 48 percent of program completion), an aircraft program realizes 91 percent of its total cost growth.
Defense Acquisition Research Journal
Kozlak, S. J., White, E. D., Ritschel, J. D. Lucas, B., & Seibel, M. J. (2017). Analyzing cost growth at program stages for DoD aircraft. Defense Acquisition Research Journal, 24(3), 386–407.