The Stratolaunch, the world’s largest all-composite aircraft, successfully completed its first flight on April 13. The plane is designed to be used as a stratospheric launch platform for space rockets, with the first launch expected to happen next year.
The six-engine aircraft has a wingspan of 117 meters (385 feet), three times as long as the distance of the Wright brothers' first flight. Stratolaunch flew for 2.5 hours over the Mojave Desert, achieving a maximum speed of 304 kilometers (189 miles) per hour and an altitude of 5,181 meters (17,000 feet).
During this maiden voyage, a variety of maneuvers were tested out to calibrate speed and test the plane's flight control systems. The engineers also conducted some simulated landing exercises before the plane came back down and landed at the Mojave Air and Space Port.
“What a fantastic first flight,” Jean Floyd, CEO of Stratolaunch, said in a statement. “Today’s flight furthers our mission to provide a flexible alternative to ground-launched systems. We are incredibly proud of the Stratolaunch team, today’s flight crew, our partners at Northrup Grumman’s Scaled Composites and the Mojave Air and Space Port.”
The vehicle’s center wing is reinforced and designed to hold multiple launch vehicles with a combined weight of up to 230,000 kilograms (500,000 pounds). The Stratolaunch is expected to be used to deliver Northrop Grumman’s Pegasus XL rocket to a suitable altitude to then shoot out of the atmosphere. It has an available payload of 370 kilograms (816 pounds). The rocket has had over 35 successful launches so the team is confident that it will successfully reach orbit.
The company, Stratolaunch Systems Corporation, was started by the late Paul G. Allen, co-founder of Microsoft. Stratolaunch originally had plans to develop a line of in-house space vehicles, including crewed crafts. Those plans were halted after the death of Allen, who passed away last October.
“We all know Paul would have been proud to witness today’s historic achievement,” said Jody Allen, Chair of Vulcan Inc. and Trustee of the Paul G. Allen Trust. “The aircraft is a remarkable engineering achievement and we congratulate everyone involved.”
The launch of a Pegasus XL rocket is expected to take place at some point in 2020 from double the altitude achieved in this first flight.