The Space Launch Initiative (SLI) was a NASA and U.S. Department of Defense joint research and technology project to determine the requirements to meet all the nation's hypersonics, space launch and space technology needs. It was also known as the "2nd Generation Reusable Launch Vehicle (RLV) program.".[1] The program began with the award of RLV study contracts in 2000.[1]
The primary goal of the research was to increase safety and reliability and to reduce overall costs associated with building, flying and maintaining the nation's next generation of space launch vehicles. NASA anticipated that these advances would revitalize the nation's space transportation capabilities, and dramatically improve NASA's ability to conduct science and exploration missions in space.[2] This program was evolved into the Orbital Space Plane Program and the Next Generation Launch Technology program in November 2002.[3]
In 2004 NASA moved on to the Constellation Program, part of the Vision for Space Exploration, after the Columbia disaster.