Steidle noted that the Office of Exploration Systems is reliant on other NASA program offices for significant activities that are critical to achieving the complete vision. The Office of Space Science plans several lunar and Mars precursor projects that intend to accomplish important science objectives and gain engineering data needed to support design decisions for human spaceflight to both destinations. Additionally, one role of the Office of Biological and Physical Research will be to conduct life science research to help understand and mitigate the health hazards associated with human spaceflight to deep space destinations.

Steidle expects to bring his past Department of Defense acquisition experience in spiral development6 to bear on the acquisition of hardware elements necessary to achieve the exploration vision. A Project Constellation timeline has been established to reflect the initial spiral phase to achieve the first flight of the unmanned crew exploration vehicle (CEV) in the 2011 time frame and the second spiral phase to achieve the first manned CEV flight in the 2014 time frame. Follow-on spirals will be needed to achieve crewed flights to Mars in the far-term.

Steidle presented the new Office of Exploration Systems, which consists of three divisions: the business operations division, the requirements division, and the development programs division. The business operations division will focus on acquisition strategy and business management, program assessment, resource management, and information management and dissemination. The requirements division will be responsible for requirements formulation, systems integration, and exploration analysis. The development programs division has responsibility for human and robotic technology, exploration transportation systems (Project Constellation), and nuclear systems development (Project Prometheus). The divisions will coordinate their work with a hand-off from requirements to development. Level 0 and Level 1 requirements are formulated within the requirements division with the help of an embryonic project team, and later the project teams are transitioned and discipline engineers added to carry projects through remaining development cycles.

Steidle stressed the need to provide competitive incentives and opportunities to come up with the technology development necessary for the new vision. Centennial Challenges is a feature of the new Exploration Vision that will use cash awards to stimulate innovation and competition in technical areas of interest to civil space and aeronautics. Specifically, the Centennial Challenges is a low risk program designed to (1) encourage innovation in ways that standard federal procurement cannot, (2) enrich NASA research by reaching new communities, (3) help address technology pitfalls, (4) promote returns that outweigh the investment, and (5) educate, inspire, and motivate the public.


The spiral model of development was a term coined in 1988 by Barry Boehm, a member of the software community, in response to software development failures. Boehm formally defines the spiral development model in a 2000 report (Spiral Development—Experience and Implementation Challenges, CMU/SEI-2000-SR-006, February 9-11, 2000, p. 9); however, the DOD commonly uses the following definition: An iterative process for developing a defined set of capabilities within one increment. This process provides the opportunity for interaction between the used, tester, and developer. In this process, the requirements are refined through experimentation and risk management, there is continuous feedback, and the user is provided the best possible capability within the increment. Each increment may include a number of spirals. (USD(AT&L), memorandum dated April 12, 2002)

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