This summer, the SpaceShipTwo (SS2) spacecraft and its WhiteKnightTwo (WK2) carrier is expected to begin initial tests to "shakedown" the spaceflight system designed by aerospace pioneer Burt Rutan and his firm Scaled Composites.

According to an announcement from Virgin Galactic yesterday, the construction of the WK2 carrier aircraft — the world's largest, all-carbon-composite aircraft — is now very close to completion at Scaled Composites in Mojave, Calif.

The WK2 mothership looks like two aircraft joined at the wing tip except for the pairs of jet engines located under the opposite, non-joined wings. The carrier aircraft is now 23.7 m (78 ft.)-long, still has a wingspan of 42.7 m (140 ft.), with a tail height of 7.62 m (25 ft.).

Its integration is now 80 percent complete — with the assembly of the wing underway in preparation for its mating with the twin fuselages.

According to the Virgin Galactic press statement:

The WK2 mothership is powered by four Pratt and Whitney PW308A engines which are amongst the most powerful, economic and efficient engines available. The WK2 mothership has also been designed to be capable of lifting other payload and launching it into space.

The joint wing between two fuselages will carry the SS2, which will hang underneath.

An artist's interpretation of how SpaceShipTwo will be carried between the two fuselages of White Knight II
Credit: Virgin Galactic

SS2, looking like a large fat cigar with a jet engine at the aft end and small changeable wings, is now nearly 60 percent complete. Unlike SpaceShipOne (SS1), which launched from underneath its single-cabin WhiteKnight (WK1) carrier, the new craft will drop from a twin-cabin high-altitude jet that can double as a space-tourist training craft. Equipped with four Pratt & Whitney Canada's PW308 engines, the WK2 launch aircraft will take off like an airplane with the manned SS2 attached underneath. It will launch SS2 into suborbital space from about 50,000 feet.

FlightGlobal.com reports:

The SS2 is 18.3 m (60 ft.) long, has a wingspan of 12.8 m (42 ft.), a tail height of 4.5 m (14.7 ft.) with a passenger cabin that is 3.66 m (12 ft.) long and 2.28 m (7.48 ft.) in diameter. Despite being so much larger than SS1, SS2 will still use a front nose skid, and not nose gear. Released at 50,000 ft. (15,200 m) by WK2, the rocket glider's apogee is expected to be up to 110 km (68 miles).

SS2 incorporates both the lessons learned from the SS1 program and market research conducted by Virgin Galactic into the requirements future astronauts have for their space flight experience. It also has built-in flexibility to encompass future requirements for other scientific and commercial applications

The engines, coupled with the light weight gained through the use of a high percentage of composite made by Scaled Composites, provide "sufficient lifting capability to launch unmanned vehicles designed to carry small satellites and other scientific payload into low earth orbit," according to Virgin Galactic and Scaled Composites.

In addition to flights originating from Spaceport America located near the White Sands Missile Area, Sierra County, in southwestern New Mexico, Virgin Galactic plans to offer "additional trips through the aurora borealis to launch from Kiruna, Sweden, Space.com says.

Approximately 85,000 people have registered as interested in flying.

The current 200+ customers cannot yet schedule their flights precisely until the aircraft have met safety regulations set by authorities. Although, WK2 pilot training has already begun — ahead of schedule — commercial operations are expected to begin in 2010.

Astronaut orientation for spaceflight is progressing well, and, already 80 of SS2's first passengers have been through medical assessment and centrifuge training at the National Spaceship Training & Research Center (NASTAR) in Philadelphia, according to Virgin Galactic.

For those of you who don't have a spare $200,000 laying around, the price may come down later. The deposit now is $20,000.

Earlier Transporting Space Tourists at 4x the Speed of Sound

Resources

Virgin Galactic Heralds 'The Year of the Spaceship' with the Unveiling of the Designs of SpaceShipTwo and WhiteKnightTwo
Virgin Galactic

Pratt & Whitney Canada Joins Virgin Galactic to Celebrate Unveiling of SpaceshipTwo and WhiteKnightTwo Models
Pratt & Whitney, Jan. 23, 2008

Virgin Galactic Unveils Suborbital Spaceliner Design
by Tariq Malik
Space.com, Jan. 23, 2007

Virgin Galactic Unveils Dyna-Soar Style SpaceShipTwo Design and Twin-Fuselage White Knight II Configuration
by Rob Coppinger
FlightGlobal.com, Jan. 23, 2008