Thực đơn
X-42 Pop-Up Upper StageThực đơn
X-42 Pop-Up Upper StageLiên quan
X-42 Pop-Up Upper Stage X-41 Common Aero Vehicle X-47A Pegasus X-20 Dyna-Soar X-44 MANTA X-26 Frigate X-4 Bantam XB-42 MixmasterTài liệu tham khảo
WikiPedia: X-42 Pop-Up Upper Stage http://www.fas.org/spp/military/program/launch/x-4... http://www.globalsecurity.org/space/systems/x-42.h...