Maximum Altitude: 62 km (203,000 ft)[16] Primary Internal Payload: 120 kg (260 lb)[19] Secondary payload spaces include a small area inside the cockpit behind the pilot or outside the vehicle in two areas in the aft fuselage fairing.[19] Aluminum LOX tank Mach 2 (1,522 mph) speed of ascent[20] 4G re-entry loading[20]