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"There is a lack of clarity regarding what the Certifying Official is actually addressing."

"Neither view was the intent of the original certification plan. The intent was a partnership that leveraged the commercial practices and experience of SpaceX and decades of Air Force experience to meet the needs of the Air Force for confidence in the capability and reliability of the SpaceX launch system. In particular, it was never envisioned that the Air Force would drive changes in design, processes, and organization to achieve certification. Neither was it expected the Falcon 9 launch experience would suffice to provide the needed confidence in Falcon 9 v1.1 for national security payloads. Instead, it was expected there would be a manageable set of issues requiring resolution, some requiring resolution at the top level."


  • [Paper] [Presentation] Edgar Zapata, Carey McCleskey, "An Analysis and Review of Measures and Relationships in Space Transportation Affordability," 50th AIAA / SAE / ASEE Joint Propulsion Conference, 2014.



"On May 2, 2007, the Air Force waived the requirement for Boeing to provide certified cost or pricing data for a significant amount of hardware associated with the production contract. The hardware is still being used, and the waiver, while officials believe it afforded DOD a reduced price, has limited government insight into cost or pricing data on a large lot of launch vehicle hardware, including engines, purchased at that time. The lack of certified cost or pricing data for this hardware has contributed to years of Defense Contract Audit Agency (DCAA) reports that consistently find ULA proposals inadequate for government evaluation and contract negotiation."



"As shown in Figure 5.1, the Project Budget showed that peak funding would occur in the same year as the Project PDR and that Project costs would go down by 16% in FY 2009 and 58% in FY 2011. Historically, the cost profiles of projects continue to increase after PDR. Based on the technical status of the Project, the prior deferral of spacecraft development, and the complexity of the integration and testing phase, this was a highly suspect budget profile."


"This type of error is not the exception - but the rule. The paradox that remains to be solved can be framed into the following question: How do we estimate something we don't yet know we need? A variation of this question is: How do we estimate requirements which management is not yet prepared to acknowledge? When "deferred or unrecognized requirements" are finally clear enough to deal with, the Change Requests (CR's) initiated inevitably affect cost and schedule in a problematic way. Too often (by the end of the project) final costs incurred were not based on the initial BOE, thus making it impossible to reconcile final costs with initial estimates. When the real costs eventually come home to roost and the full extent of project growth can be clearly seen, the estimator rightfully states that what was actually built - was NOT what was originally estimated."


"Affordable and sustainable space exploration remains an elusive goal. We explore the competitive advantages of evolving towards independent operators for space transportation in our economy. We consider the pros and cons of evolving business organizations that operate and maintain space transportation system assets independently from flight system manufacturers and from host spaceports."


"Designers of space launch systems should be cognizant of the impact of their design assumptions on operational characteristics. Operational metrics such as turnaround time, recurring cost, and headcount are critical factors for the future viability of such systems. The results presented here are from a study that seeks to determine in what manner design approaches can improve the operability of future space launch systems. This is accomplished by applying such operational approaches at the start of the concept design process."



  • "Alternate Trajectories - Options for Competitive Sourcing of the Space Shuttle Program" Report of the Space Shuttle Competitive Sourcing Task Force, RAND, 2002.







From pp.10, one of the more unique cost analysis of the entire Shuttle program.


"The history of the certification principles for these engines is confusing and difficult to explain. Initially the rule seems to have been that two sample engines must each have had twice the time operating without failure as the operating time of the engine to be certified (rule of 2x). At least that is the FAA practice, and NASA seems to have adopted it, originally expecting the certified time to be 10 missions (hence 20 missions for each sample). Obviously the best engines to use for comparison would be those of greatest total (flight plus test) operating time -- the so-called "fleet leaders." But what if a third sample and several others fail in a short time? Surely we will not be safe because two were unusual in lasting longer. The short time might be more representative of the real possibilities, and in the spirit of the safety factor of 2, we should only operate at half the time of the short-lived samples."


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Website Contact: Edgar Zapata, NASA Kennedy Space Center