TYPE: Technology demonstrator.

PROGRAMME: Design concepts for 'Tier One' suborbital manned spacecraft inaugurated 1996; SpaceShipOne development programme began with award of customer contract in April 2001; aircraft registered N328KF (signifying non-metric equivalent of 100,000 m) on 20 March 2003 and existence revealed 18 April 2003. Initial two sorties (first unmanned, second manned) on 20 May and 29 July 2003 were captive-carry flights under company's White Knight aircraft; followed by first manned glide 7 August 2003; first 'feather' conversion made on fourth flight, 27 August 2003. Pitch-up problem encountered during third gliding flight on 23 September; rectified, and flying resumed, 17 October 2003. First Supersonic flight, reaching almost M1.2 and 20,725 m (68,000 ft) was made on the 17 December 2003 Wright brothers centennial anniversary, after release from White Knight at 14,630 m (48,000 ft). On same date, telecommunications and entertainments businessman Paul G Allen identified as project's sponsor.

DESIGN FEATURES: Rocket-powered research aircraft, designed primarily using CFD and intended for suborbital flights to 100 km (62 miles) altitude following air launch from White Knight at approximately 15,240 m (50,000 ft). Unique configuration enables aircraft-like qualities for boost, glide and landing phases. Craft converts, via pneumatically actuated 'feather' of control surfaces, to a stable, high-drag shape to re-enter atmosphere, allowing 'hands off' re-entry and greatly reduced aerodynamic and thermal loads.

FLYING CONTROLS: Three flight control systems: manual subsonic, electric supersonic, and cold-gas remote control system. Each vertical tail surface has a manual upper rudder for subsonic flight and an electrically actuated lower rudder for trim and supersonic control; upper rudders deflect outward only. Horizontal tail surfaces, outboard of each vertical fin, comprise an electric, all-flying stabiliser for trim and supersonic control, with a manual elevon for subsonic pitch and roll. Beyond Earth atmosphere, roll, pitch and yaw are controlled by redundant pneumatic attitude thrusters at outer ends of wing leading-edges (roll) and at front of cabin (pitch and yaw).
Wings have no control surfaces as such; instead, entire one-third of wing trailing-edge, plus adjacent booms and tail surfaces, are hinged to 'feather' 65° upwards by pneumatic addition, creating a high-drag configuration which decelerates craft for re-entry and permits a high AoA steep descent before 'defeathering' the configuration for a glide landing.
Craft enters shallow glide-climb after release from White Knight before igniting rocket and rotating into near-vertical climb for 65 seconds until rocket burnout, when it continues in zero-g climb for about 3½ minutes to reach 100 km altitude before starting free fall back towards Earth.

STRUCTURE: Monocoque structure; construction as described for White Knight. NO2 tank attached to rear fuselage walls by silicone rubber. Suspended from White Knight by fore and aft hooks with spring release.

LANDING GEAR: Rearward-retracting 'tricycle', comprising twin mainwheels and nose skid.

POWER PLANT: Specially developed hybrid rocket propulsion system, using non-toxic liquid nitrous oxide (NO2) and hydroxy-terminated polybutadiene (HTPB) fuel. Development of fuel, bulkhead, controller, valve, injector, igniter and ground test programme was completed by Environmental Aeroscience Corporation of Miami and SpaceDev of San Diego; first firing November 2002; latter's system selected in September 2003. Composites NO2 tank and case, throat and nozzle components developed by Scaled; tank's filament-wound carbon fibre over-wrap provided by Thiokol; ablative nozzle supplied by AAE Aerospace.

ACCOMMODATION; Three-place cabin, with space-qualified environmental control system; otherwise as described for White Knight. Cabin can be heated by engine bleed air while attached to White Knight.

SYSTEMS: Pneumatic system, pressure 414 bar (6,000 lb/sq in), actuates wing/tail 'feather', spaceflight attitude control thrusters, cabin pressurisation and window demisting. Hydraulic system for wheel brakes only. Lithium batteries for electrical power. Bottled oxygen system for emergency use.

AVIONICS: Flight: New INS-GPS nav/flight director developed jointly by Scaled Composites and Fundamental Technology Systems of Orlando, Florida, provides pilot with precise guidance information needed to fly SpaceShipOne manually during boost and re-entry, and for approach and landing; it also monitors vehicle health. Unit stores flight test data and telemeters data to mission control station.