system is supersonic. if this were full of air, we would get a sonic boom on every single revolution. you can hear a little bit. can you hear it? just a little bit? a little bit of vibration, too. arming system. here we go. so he's doing the launch sequence now. ten. nine, here we go. seven, six, five, four, three, two, one... launching. whoa! that was it. applause. yeah! decelerating system. in my mind, this has gone from nonsense to plausible in the space of a few hours. and in october last year, the first test launch in new mexico proved that the carbon fibre dart could not only launch, but also survive a landing in which it buried itself in the desert.