Scaled Composites White Knight Two
|White Knight Two|
|Designer||Robert Morgan, James Tighe|
|First flight||December 21, 2008|
|Developed from||Scaled Composites White Knight|
The Scaled Composites Model 348 White Knight Two (WK2) is a jet-powered cargo aircraft which is used to lift the SpaceShipTwo spacecraft to release altitude. It was developed by Scaled Composites in 2007-2010 as the first stage of Tier 1b, a two-stage to suborbital-space manned launch system. WK2 is based on the successful mothership to SpaceShipOne, White Knight, which itself is based on Proteus.
With an "open architecture" design and explicit plans for multi-purpose use, the aircraft could also operate as a zero-g aircraft for passenger training or microgravity science flights, handle missions in high-altitude testing more generally, or be used to launch payloads other than SpaceShipTwo. A study to look at using the aircraft as a forest fire water bomber has also been mentioned, one that would utilize a large carbon composite water tank that could be quickly replenished to make repeat runs over fires.
Virgin Galactic has ordered two White Knight Twos. Together WK2 and SS2 form the basis for Virgin Galactic's fleet of suborbital spaceplanes. Virgin Galactic is also looking into making WhiteKnightTwo the air-launch platform for a new two-stage liquid-fueled rocket small satellite launcher called LauncherOne.
As of November 2010[update], The Spaceship Company has announced that it plans to build at least three additional White Knight Two aircraft and an additional five SpaceShipTwo rocket planes. These are the aircraft to be built after the initial prototypes of each craft are built by Scaled Composites.
The first White Knight Two is named VMS Eve after Richard Branson's mother; it was officially unveiled on July 28, 2008, and flew for the first time on December 21, 2008. The second is expected to be named VMS ''Spirit of Steve Fossett'' after Branson's close friend Steve Fossett, who died in an aircraft accident in 2007.
White Knight Two is roughly three times larger than White Knight, in order to perform a captive flight with the larger SpaceShipTwo spacecraft. The WK2 is similar in wingspan to a Boeing B-29 Superfortress. White Knight Two is a very modern aircraft, as even the flight control cables are constructed of carbon fiber, using a new patented design.
WK2 will provide preview flights offering several seconds of weightlessness, before the suborbital event. It is intended to have a service ceiling of about 60,000 ft (18 km), offering a dark blue sky to passengers. This will allow tourists to practice before the real flight.
White Knight Two consists of a twin boom with two jet engines per hull. One hull is an exact replica of that of SpaceShipTwo (to allow tourist training), and the other will carry 'cut-rate' day-trippers into the stratosphere.
The design is quite different from the White Knight, both in size, use of tail, engine configuration and placement of cockpit(s). The White Knight uses two T-tails, but the White Knight Two uses two cruciform tails. Engine configuration is also very different. White Knight Two has four engines hung underneath the wings on pylons while White Knight's pair of engines are on either side of its single fuselage.
Timeline of commercial introduction 
- On January 23, 2008 the White Knight Two design was revealed.
- On July 28, 2008 the completion and rollout of the first aircraft, Eve, (Tail Number: N348MS) occurred at Scaled's Mojave headquarters. Branson predicted that the maiden space voyage would take place in 18 months: "It represents... the chance for our ever-growing group of future astronauts and other scientists to see our world in a completely new light."
- On March 22, 2010 the VSS Enterprise completed its captive maiden voyage of 2 hours and 54 minutes, ascending to an altitude of 45,000 feet (13716 meters).
The launch customer of White Knight Two is Virgin Galactic, which will have the first two units, and exclusive rights to the craft for the first few years.
Flight test program 
An extensive flight test program of VMS Eve, with nearly twenty flights between December 2008 and August 2009, was undertaken to validate the design and gradually expand the aircraft operating envelope. The flight tests were complete by September 2009, and testing with SpaceShipTwo began in early 2010.
Aircraft specifications 
Data from Virgin Galactic Presentation 2007
- Crew: 2 (flight crew) + spaceship launch crew
- Capacity: payload 17,000 kg (37,000 lb) to 50,000 ft (15,000 m).; 200 kg satellite to LEO when carrying a LauncherOne orbital launch vehicle.
- Length: 78 ft 9 in (24 m)
- Wingspan: 141 ft 1 in (43 m)
- Powerplant: 4 × Pratt & Whitney Canada PW308 turbofan engines, 6,900 lbf (30.69 kN) thrust each
- Service ceiling: 70,000 ft (21,000 m) 
- US patent D612791, Tighe, James, "U.S. Design Patent 612,719 for the ornamental design for an aircraft", issued 2010-03-30
- "WK2 Rollout Audio Clips (parts 4 & 6)". Movaje Skies. 2008-07-30. Retrieved 2009-03-10.
- Leonard David (June 6, 2008). "Virgin Galactic Spaceline: Mega-Mothership Set for Rollout Debut". SPACE.com. Retrieved 2008-06-10.
- Malik, Tariq (2008-01-23). "Virgin Galactic Unveils Suborbital Spaceliner Design". SPACE.com. Retrieved 2008-01-25.
- Rob Coppinger (11 July 2012). "Virgin Galactic Unveils LauncherOne Rocket for Private Satellite Launches". Space.com.
- Spacecraft factory to break ground in Mojave, Los Angeles Times, 2010-11-08, accessed 2010-11-09.
- Burack, Ari (10 October 2007). "Sir Richard Branson...". San Francisco Sentinel. Retrieved 2008-02-28.
- "Spaceship Company unveils design of SpaceShipTwo". Pravda Online. 2008-01-23. Retrieved 2008-01-25.
- "Something dangerous and new". thespacereview.com. August 28, 2007. Retrieved 2007-08-28.
- Leonard David (11 August 2006). "Burt Rutan on Civilian Spaceflight, Breakthroughs, and Inside SpaceShipTwo". Space.com. Retrieved 2007-08-25.
- Kenny Kemp (March 2007). Destination Space. Virgin Books.
- Spencer Reiss (May 22, 2007). "Burt Rutan and Richard Branson Want You to Hit Space in High Style". Wired.com. Retrieved 2007-08-25.
- bbc.co.uk, Branson unveils space tourism jet
- space.newscientist.com, Virgin Galactic rolls out SpaceShipTwo's 'mothership'
- New Scientist Space and Reuters (23 January 2008). "Virgin Galactic unveils model of SpaceShipTwo". New Scientist. Retrieved 8 December 2009.
- "FAA N Number Registration for "Eve"". Retrieved 2008-07-28.
- "First flight for SpaceShipTwo". Retrieved 2010-03-22.
- Scaled Composites, "White Knight Two Flight Test Summaries" (accessed 2009-10-01)
- "Scaled plans 50,000ft WhiteKnight Two flight by September". Flight International (Reed Business Information). 30 April 2009. Retrieved 8 December 2009.
- Will Whitehorn and Alex Tai (2007-07-22). "Virgin Galactic presentation Oshkosh Theater in the Woods 2007". BrightCove.TV. Retrieved 2007-09-22.
- Rob Coppinger (9 December 2008). "Virgin Galactic in SpaceShipThree talks". Flightglobal. Retrieved 2008-12-09.
- Will Whitehorn (2009-10-27). International Astronautical Congress 2009: Civilian Access to Space (video, comments at c. 9:00). Daejeon, Korea: Flightglobal Hyperbola, Rob Coppinger.
|Wikimedia Commons has media related to: White Knight Two|
- BBC - In pictures: Space tourism jet
- Video of White Knight Two being unveiled
- Photos of Virgin Galactic’s White Knight Two unveiling
- Photos of cockpit and interior of White Knight Two
See also 
- Scaled Composites Proteus, predecessor to WhiteKnightOne
- Mojave Aerospace WhiteKnightOne, predecessor to WhiteKnightTwo
- StratoLaunch Systems Roc, derivative of WhiteKnightTwo
- The Spaceship Company SpaceShipTwo, payload for WhiteKnightTwo
- Virgin Galactic LauncherOne, payload for WhiteKnightTwo