Founded in 2011 by the late Paul G. Allen, a co-founder of Microsoft, the company has from the very start been working to develop the gigantic flying launch pad. The plane has been designed to carry satellites into low-Earth orbit - achieved by launching vehicles to a cruising altitude of 36,000 feet (11,000 meters), reports Geek Wire.
Comment: Or so they say. There are far less expensive projects already way ahead of the curve on this.
At this point, the aircraft - called Roc - becomes a mobile launch pad, and it will release the satellites and their launchers into orbit. On completing the task, the aircraft is designed to land back on Earth. The plane needs a runway at least 3,700 meters (12,000 ft) long to take off and land.
The massive plane which incorporates parts from two Boeing 747 jumbo jets is powered by six huge Pratt & Whitney turbofan engines and can carry a payload of over 230,000 kg (500,000 lb).
Comment: Which isn't enough for most space deliveries.
Stratolaunch has been designed to have a range of 2,200 km (1,200 miles) at 35,000 feet when flying an air launch mission, according to Digital Journal.
Stratolaunch Services is close to being in a position to offer satellite launch services to the military, private companies and even NASA itself as a more economical way to get into space. "Whatever the payload, whatever the orbit, getting your satellite into space will soon be as easy as booking an airline flight," said CEO Jean Floyd in 2018, reports CNN.
Comment: More economical? The project has already cost a fortune! And it can't carry anything near the payloads rockets carry.
Jack Beyer, an aerospace and launch photographer for NASASpaceFlight.com, told CNN last week the plane was "so big it seems like it shouldn't be able to fly." But the plane has generated a great amount of interest. Photographers and industry bloggers were already gathered at the site Saturday morning to see history being made.
"People are interested in the first flight of Stratolaunch because they want to see the future," Beyer said. "It's the same reason why people tune in each year to watch the Apple keynotes. People want to see what's next."
In an emailed statement in January, Stratolaunch told Geek Wire it was discontinuing its programs to develop a new type of rocket engine and a new line of rockets, but will continue to work on its huge, double-bodied plane designed to serve as a flying launch pad for rockets.
"We are streamlining operations, focusing on the aircraft and our ability to support a demonstration launch of the Northrop Grumman Pegasus XL air-launch vehicle. We are immensely proud of what we have accomplished and look forward to a first flight in 2019," read the email.
To date, the heaviest payload sent to LEO is the one carried by Saturn V (moon landers with their own rockets and cargo) which was 140 t. But the whole rocket weighed ~2970 t. The advantage of Stratolaunch, at least in theory, is clear. Of course it's projected to carry much smaller weight in normal operations, for example three Pegasuses XL (3x23.1 t), but there is a room for upgrade, if everything works. It may also be used for some unsavoury means, but which of space launching systems cannot?