2017 US Code
Title 42 - The Public Health and Welfare
Chapter 159 - Space Exploration, Technology, and Science
Subchapter II - Expansion of Human Space Flight Beyond the International Space Station and Low-Earth Orbit
Sec. 18322 - Space Launch System as follow-on launch vehicle to the Space Shuttle

The Administrator shall, as soon as practicable after October 11, 2010, initiate development of a Space Launch System meeting the minimum capabilities requirements specified in subsection (c).

In order to limit NASA's termination liability costs and support critical capabilities, the Administrator shall, to the extent practicable, extend or modify existing vehicle development and associated contracts necessary to meet the requirements in paragraph (1), including contracts for ground testing of solid rocket motors, if necessary, to ensure their availability for development of the Space Launch System.

(1) In general.—The Space Launch System developed pursuant to subsection (b) shall be designed to have, at a minimum, the following:

(2) Flexibility.—The Space Launch System shall be designed from inception as a fully-integrated vehicle capable of carrying a total payload of 130 tons or more into low-Earth orbit in preparation for transit for missions beyond low-Earth orbit. The Space Launch System shall, to the extent practicable, incorporate capabilities for evolutionary growth to carry heavier payloads. Developmental work and testing of the core elements and the upper stage should proceed in parallel subject to appropriations. Priority should be placed on the core elements with the goal for operational capability for the core elements not later than December 31, 2016.

(3) Transition needs.—The Administrator shall ensure critical skills and capabilities are retained, modified, and developed, as appropriate, in areas related to solid and liquid engines, large diameter fuel tanks, rocket propulsion, and other ground test capabilities for an effective transition to the follow-on Space Launch System.

(4) The capacity for efficient and timely evolution, including the incorporation of new technologies, competition of sub-elements, and commercial operations.