Commercial Orbital Transportation Services program
Commercial Orbital Transportation Services program or COTS is a NASA program to coordinate the delivery of cew and cargo to the International Space Station though private companies. COTS is primarily related to the development of vehicles which would be able to engage in Commercial Resupply Services missions, mainly though non-binding contracts as well as Space Act Agreements. These are often based around NASA providing milestone-based payments to companies participating in the program.
The program consists of four "parts", or capabilities that are sought to be developed:
- Capability level A: External unpressurized cargo delivery and disposal
- Capability level B: Internal pressurized cargo delivery and disposal
- Capability level C: Internal pressurized cargo delivery, return and recovery
- Capability level D: Crew Transportation.
In participating for the money for the program, NASA initially selected six semifinalists in Phase I of the COTS program in May 2006. These companies included Andrews Space, Rocketplane Kistler, SpaceDev, Space Exploration Technologies, SpaceHab, and Transformational Space Corporation. Later in 2006, NASA narrowed down the field to SpaceX and Rocketplane Kistler. By the end of 2007, NASA had terminated Rocketplane Kistler's COTS agreement due to the company failing to raise sufficient private funding. This resulted in a second round of funding, resulting in Orbital Sciences Corporation being selected for the remaining funding.
As of the beginning of 2011, the COTS-D option has yet to be funded, with companies such as SpaceX making public announcements and requests for the option to be funded.