A year ago we had news of the Stratolaunch launch system. After numerous delays and changes in strategy, the company announced that it was moving ahead with its intention to build the largest aircraft in the world and use it as a satellite launch pad. Recently, at last, we were able to see the first images of the gigantic Roc plane almost complete. The company has decided to take the giant to walk for the first tests of refueling and, incidentally, so that the press does not forget the project.
The Roc plane of Stratolaunch Systems – its technical name is Scaled Composites Model 351- was built from the fuselage of two former Boeing 747s of United Airlines. It has a mass of almost 325 tons (including one hundred tons of fuel), a length of 73 meters and a wingspan of about 117 meters, making it the largest airplane in the world in terms of wingspan, although the Boeing 747, Airbus A380 or the Antonov An-225 are longer. Roc is capable of carrying up to 250 tonnes of external payload thanks to six Pratt & Whitney PW4056 engines. As we see in the images, Roc still has a lot to be complete, but at least it is already in one piece.
The Stratolaunch project was born in 2011 by millionaire Paul Allen with the aim of launching a version of Falcon 5 of SpaceX capable of placing 6.1 tons in low orbit, something never seen in an aerial launch system. SpaceX quickly withdrew from the project and was replaced by Orbital Sciences, which wanted to use Roc as a platform for the Pegasus 2 rocket, later named Thunderbolt. Orbital also retired in 2014 and for a time the future of the company was in a limbo, although it was played with the idea of using the Stratolaunch aircraft to launch a small version – a 75% – of the winged Dream Chaser.
Finally, in June of last year Stratolaunch joined forces again with Orbital, now Orbital ATK, to launch small rockets Pegasus XL. The decision was a real surprise considering that using such a plane to launch such a small rocket is at least a bit disproportionate. Of course, not to lose the load capacity will be launched three Pegasus rockets in a single mission (each with a mass of 25 tons). Is this enough to justify the profitability of Stratolaunch? No one knows, but no one misses that the business model is somewhat peculiar, especially before the competition of Virgin Galactic. This company plans to use a Boeing 747 to launch its Launcher One rocket. Launcher One will be able to put 400 kg in orbit in LEO, a figure comparable to a single Pegasus, but in return it is assumed that the maintenance costs and the associated infrastructures will be much smaller than in the case of Stratolaunch.
Stratolaunch will use the runway of California's Mojave Air and Space Port or the former Kennedy Space Center shuttle runway as a base of operations. He later hopes to be able to use other tracks around the world if the demand for releases is high enough. Will Stratolaunch gain a foothold in the competitive international launch market?