allows it to use ex-gone -- oxygen in the atmost fear to care -- to carry fuel rather than tanks. >> the ultimate vision is paying pay load into space at a much more affordable cost. >> the x51 traveled 170 miles in 200 seconds, opening the door to all sorts of military and commercial applicables. >> that would get you from l.a. to new york in about 44 minutes, if cue fly that duration. >> without the need to carry its own oxygen, this so-called scram jet engine can go tpa*ers and further while burning less fuel. the first person to know it worked, the b52 pilot who launch thunderstorm. >> we're looking out the window and looking for it and you see something out of nowhere, this rocket screams by about a bright plume. >> we saw the vig, it was on profile, and people started screaming. it was really exciting, in the control room. >> and the -- and the aircraft itself is made out