商業軌道輸送サービス
The Dream Chaser spacecraft is based on the HL-20 lifting-body design. It was developed by SpaceDev for the 2004 Commercial Orbital Transportation Services competition and was being developed by Sierra Nevada Corporation for the Commercial Crew Development program (CCDev). The crewed Dream Chaser was not selected by NASA for the final phase of development of commercial crew (CCtCap). However, the cargo Dream Chaser was selected by NASA for its Commercial Resupply Services 2 (CRS2) program.