|Published: April 2019|
The World’s largest aircraft took off for its first flight over the Mojave Desert in California April 13. The carbon-composite air-launch carrier plane built by Stratolaunch Systems Corporation’s has been years in development before soaring on its debut flight lasting 2:30 hours without issue. Stratolaunch Systems was started by late Microsoft co-founder Paul Allen in a bid to enter the lucrative private space market by offering an alternative and cost-effective air-launch system to put satellites into orbits.
The white airplane called ‘Roc’ – named after the enormous mythological bird of prey – with a wingspan the length of an Americal football field, sporting six engines of size that power the Boeing 747 ‘Jumbo’ airliners and twin fuselages landed back at the Mojave Air and Space Port amid cheers from hundreds of people gathered to witness the great aeronautical event.
“What a fantastic first flight. Today’s flight furthers our mission to provide a flexible alternative to ground-launched systems”, Stratolaunch CEO Jean Floyd said in a statement posted to the company’s website.
The plane is designed to launch rockets and other space vehicles weighing up to 500,000 lb at an altitude of 35,000 ft and has been claimed by the company as making satellite deployment as easy as booking an airline flight.
The company seeks to cash in on demand for vessels that can put satellites in orbit, while competing with other US space entrepreneurs and industry leaders such as Elon Musk’s SpaceX and United Launch Alliance – a partnership between Boeing and Lockheed Martin.
Initially, Stratolaunch had planned to work with SpaceX to develop a launch vehicle, notionally called the Falcon 5. The goal was to build a four or five engine variant of the Falcon rocket designed for air-launch. However, work between the companies ended in 2012, after SpaceX determined that too many modifications were required.
As a result, Orbital Sciences (now Northrop Grumman) was selected to replace SpaceX. Unlike SpaceX, Orbital already had a proven air-launch vehicle in the Pegasus – a rocket with 29 successful launches in a row.
As a starter ‘Roc’ will be used to launch up to three Pegasus rockets in a sinlge launch – two of which are already being assembled at Vandenberg Air Force Base – perhaps as early as in 2020.
Interestingly, While both fuselages of Roc have windows, the three-person crew will fly in the right fuselage. The left fuselage is not human rated and thus will only house electronics. As mentioned earlier, the plane is propelled by six jet engines which have been salvaged from two 747s. Additional components from the 747s were also utilised, including landing gear, windows, avionics, and actuators.
The wingspan of the carrier aircraft is a world record breaking 385 feet (117 meters) – long enough for the Wright brothers to complete their historic flight three times. Additionally, it also makes the carrier wider than the Saturn V rocket is tall.
In addition to the massive wingspan and a carrying capacity of 549,290 pounds (249,153 kilograms), the carrier has a 1,000 nautical mile mission radius. These metrics also create the potential for larger launch vehicles to be launched from the aircraft, as the plane is not exclusively designed for Pegasus.
These launch architectures differ from traditional vertically launched rockets in that they are carried above the densest part of the atmosphere by a carrier aircraft, before being released to launch to space.
This lowers the cost needed to escape Earth’s atmosphere by utilisng less costly jet fuel and a reusable carrier aircraft. It also avoids many weather restrictions present in lower parts of the atmosphere and offers more flexibility for launch inclinations than fixed launch pads.