TechSat-21 (Technology Satellite of the 21st Century) was a small spacecraft developed by the U.S.

Air Force Research Laboratory The Air Force Research Laboratory (AFRL) is a scientific research organization operated by the United States Air Force Materiel Command dedicated to leading the discovery, development, and integration of aerospace warfighting technologies, pl ...

's Space Vehicles Directorate to test technology for formation flight of spacecraft which can rapidly change formation based on mission requirements. The project was canceled in 2003 due to numerous cost overruns.

References

Cancelled spacecraft Technology demonstration satellites Satellites of the United States Air Force {{US-spacecraft-stub