page_title: Scaled Composites White Knight Two
section_title: Design
hierarchical_section_title: Scaled Composites White Knight Two / Design
caption_attribution_description: Pratt &amp; Whitney PW308, the engine used on the Scaled Composites / Virgin Galactic White Knight Two
context_page_description: The Scaled Composites Model 348 White Knight Two is a quadjet cargo aircraft that is used to lift the SpaceShipTwo spacecraft to release altitude. It was developed by Scaled Composites from 2007 to 2010 as the first stage of Tier 1b, a two-stage to suborbital-space crewed 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 of use of 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.
  The first White Knight Two is named VMS Eve after Richard Branson's mother Eve Branson; it was officially unveiled on July 28, 2008, and flew for the first time on December 21, 2008.
context_section_description: 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 is of twin fuselage design with four jet engines mounted two on each wing. One fuselage is an exact replica of that of SpaceShipTwo (to allow tourist training), and the other will offer 'cut-rate' trips to 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.
caption: PW308 used on the White Knight Two
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