The Scaled Composites Model 348 White Knight Two (WK2) is a

quadjet A four-engined jet, sometimes called a quadjet, is a jet aircraft powered by four Jet engine, engines. The presence of four engines offers increased power, allowing such aircraft to be used as airliners, Cargo aircraft, freighters, and military a ...

cargo aircraft A cargo aircraft (also known as freight aircraft, freighter, airlifter or cargo jet) is a fixed-wing aircraft that is designed or converted for the carriage of air cargo, cargo rather than passenger aircraft, passengers. Such aircraft usually ...

that is used to lift the

SpaceShipTwo The Scaled Composites Model 339 SpaceShipTwo (SS2) is an air-launched suborbital spaceplane type designed for space tourism. It is manufactured by The Spaceship Company, a California-based company owned by Virgin Galactic. SpaceShipTwo is car ...

spacecraft A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, p ...

to release altitude. It was developed by

Scaled Composites Scaled Composites (often called simply Scaled) is an American aerospace company founded by Burt Rutan and currently owned by Northrop Grumman. It is located at the Mojave Air and Space Port in Mojave, California, United States. Founded to develo ...

from 2007 to 2010 as the first stage of

Tier 1b Tier may refer to: Groupings * Organizational, a ranking relationship involving order in a collective and its subordinate components *Ranking, a relationship involving order between a set of observations or variables * Data center tiers, Telecom ...

, a two-stage to suborbital-space crewed launch system. WK2 is based on the successful mothership to

SpaceShipOne SpaceShipOne is an experimental air-launched rocket-powered aircraft with sub-orbital spaceflight capability at speeds of up to 3,000 ft/s (900 m/s, 3240 km/h), using a hybrid rocket motor. The design features a unique "feathering" a ...

White Knight A white knight is a mythological figure and literary stock character. They are portrayed alongside a black knight as diametric opposites. A white knight usually represents a heroic warrior fighting against evil, with the role in medieval literatu ...

, which itself is based on

Proteus In Greek mythology, Proteus (; Ancient Greek: Πρωτεύς, ''Prōteus'') is an early prophetic sea-god or god of rivers and oceanic bodies of water, one of several deities whom Homer calls the "Old Man of the Sea" ''(hálios gérôn)''. ...

. With an "

open architecture Open architecture is a type of computer architecture or software architecture intended to make adding, upgrading, and swapping components with other computers easy. For example, the IBM PC, Amiga 500 and Apple IIe have an open architecture support ...

" design and explicit plans for multi-purpose use, the aircraft could also operate as a

zero-g Weightlessness is the complete or near-complete absence of the sensation of weight. It is also termed zero gravity, zero G-force, or zero-G. Weight is a measurement of the force on an object at rest in a relatively strong gravitational fie ...

aircraft for passenger training or

microgravity The term micro-g environment (also μg, often referred to by the term microgravity) is more or less synonymous with the terms ''weightlessness'' and ''zero-g'', but emphasising that g-forces are never exactly zero—just very small (on the I ...

science flights, handle missions in

high-altitude Altitude or height (also sometimes known as depth) is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context ...

testing more generally, or be used to launch payloads other than SpaceShipTwo. A study of use of the aircraft as a

forest fire A wildfire, forest fire, bushfire, wildland fire or rural fire is an unplanned, uncontrolled and unpredictable fire in an area of Combustibility and flammability, combustible vegetation. Depending on the type of vegetation present, a wildfire ...

water bomber Water (chemical formula ) is an inorganic, transparent, tasteless, odorless, and nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known living organisms (in which it acts as a ...

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 Sir Richard Charles Nicholas Branson (born 18 July 1950) is a British billionaire, entrepreneur, and business magnate. In the 1970s he founded the Virgin Group, which today controls more than 400 companies in various fields. Branson expressed ...

's mother

Eve Branson Evette Huntley Branson (née Flindt; 12 July 1924 – 8 January 2021) was a British philanthropist, child welfare advocate, and the mother of Richard Branson. Life and career Branson was born in Edmonton, Middlesex, England, the daughter of Dor ...

; 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 James Stephen Fossett (April 22, 1944 – September 3, 2007) was an American businessman and a record-setting aviator, sailor, and adventurer. He was the first person to fly solo nonstop around the world in a balloon and in a fixed-wing aircraf ...

, who died in an aircraft accident in 2007. , it is not clear how many SS2 and WK2 vehicles will actually be built.

History

In 2008, Virgin Galactic ordered two White Knight Two vehicles. Together, WK2 and SS2 form the basis for

Virgin Galactic Virgin Galactic is an American spaceflight company founded by Richard Branson and his British Virgin Group retains an 11.9% stake through Virgin Investments Limited. It is headquartered in California, and operates from New Mexico. The company i ...

's fleet of suborbital spaceplanes. In November 2010,

The Spaceship Company The Spaceship Company (TSC) is a British/American spacecraft manufacturing company that was founded by Burt Rutan and Richard Branson in mid-2005 and was jointly owned by Virgin Group (70%) and Scaled Composites (30%) until 2012 when Virgin Gal ...

had announced that it planned to build at least three additional White Knight Two aircraft and an additional five

rocket planes, the aircraft to be built by Virgin after the initial prototypes of each craft are built by

. Spacecraft factory to break ground in Mojave
''

Los Angeles Times The ''Los Angeles Times'' (abbreviated as ''LA Times'') is a daily newspaper that started publishing in Los Angeles in 1881. Based in the LA-adjacent suburb of El Segundo since 2018, it is the sixth-largest newspaper by circulation in the Un ...

'', 2010-11-08, accessed 2010-11-09. During 2012–2014, Virgin Galactic was also considering use of the WhiteKnightTwo as the air-launch platform for a new two-stage liquid-fueled rocket small satellite launcher called

LauncherOne LauncherOne is a two-stage orbital launch vehicle developed and flown by Virgin Orbit that began operational flights in 2021, after being in development from 2007 to 2020. It is an air-launched rocket, designed to carry smallsat payloads of u ...

. In the event—by late 2015—they decided to use a larger carrier aircraft for the job.

Design

White Knight Two is roughly three times larger than

in order to perform a captive flight with the larger

spacecraft. The WK2 is similar in

wingspan The wingspan (or just span) of a bird or an airplane is the distance from one wingtip to the other wingtip. For example, the Boeing 777–200 has a wingspan of , and a wandering albatross (''Diomedea exulans'') caught in 1965 had a wingspan of ...

to a

Boeing B-29 Superfortress The Boeing B-29 Superfortress is an American four-engined propeller-driven heavy bomber, designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to its predecessor, the B-17 Fl ...

. 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 Weightlessness is the complete or near-complete absence of the sensation of weight. It is also termed zero gravity, zero G-force, or zero-G. Weight is a measurement of the force on an object at rest in a relatively strong gravitational fi ...

before the suborbital event. It is intended to have a

service ceiling With respect to aircraft performance, a ceiling is the maximum density altitude an aircraft can reach under a set of conditions, as determined by its flight envelope. Service ceiling Service ceiling is where the rate of climb drops below a pres ...

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 engine A jet engine is a type of reaction engine discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include rocket, Pump-jet, water jet, and hybrid propulsion, the term ...

s 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-tail A T-tail is an empennage configuration in which the tailplane is mounted to the top of the fin. The arrangement looks like the capital letter T, hence the name. The T-tail differs from the standard configuration in which the tailplane is ...

s, but the White Knight Two uses two

cruciform tail __NOTOC__ The cruciform tail is an aircraft empennage configuration which, when viewed from the aircraft's front or rear, looks much like a cross. The usual arrangement is to have the horizontal stabilizer intersect the vertical tail somewhere ...

s. 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 introduction

Virgin Galactic contracted aerospace designer

Burt Rutan Elbert Leander "Burt" Rutan (; born June 17, 1943) is a retired American aerospace engineer and entrepreneur noted for his originality in designing light, strong, unusual-looking, and energy-efficient air and space craft. He designed the record- ...

to build the mothership and spacecraft. On January 23, 2008 the White Knight Two design was revealed. On July 28, 2008 the completion and rollout of the first aircraft, ''

Eve Eve (; ; ar, حَوَّاء, Ḥawwāʾ; el, Εὕα, Heúa; la, Eva, Heva; Syriac: romanized: ) is a figure in the Book of Genesis in the Hebrew Bible. According to the origin story, "Creation myths are symbolic stories describing how the ...

'', ( 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 VMS ''Eve'' completed its 25th flight, the first occasion it carried the SpaceShipTwo, VSS ''Enterprise''. In a flight of 2 hours 54 minutes, it ascended to an altitude of . The launch customer of White Knight Two is

, 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

began in early 2010.

Aircraft specifications

References

External links

BBC - In pictures: Space tourism jet

Video of White Knight Two being unveiled

Photos of Virgin Galactic’s White Knight Two unveiling

{{DEFAULTSORT:Scaled Composites Whiteknighttwo WK2 VMS WhiteKnightTwo

White Knight Two The Scaled Composites Model 348 White Knight Two (WK2) 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 tw ...

WhiteKnightTwo Space tourism 2000s United States airliners Twin-fuselage aircraft 2000s United States special-purpose aircraft Rutan aircraft Quadjets Cruciform tail aircraft Aircraft first flown in 2008 Aircraft related to spaceflight