The plane, called Roc, which has a wingspan the length of an American football field and is powered by six engines on a twin fuselage, took to the air in the morning and stayed aloft for more than two hours before landing safely back at the Mojave Air and Space Port as a crowd of hundreds cheered. “What a fantastic first flight,” said Stratolaunch chief executive Jean Floyd said.
“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 Northrop Grumman’s Scaled Composites and the Mojave Air and Space Port.”
The plane is designed to drop rockets and other space vehicles weighing up to 500 000 pounds (226 796kg) at an altitude of 35 000 feet and has been billed by the company as making satellite deployment as “easy as booking an airline flight”.
Saturday’s flight, which saw the plane reach a maximum speed of 304km/* and altitudes of 17 000 feet, was meant to test its performance and handling qualities, according to Stratolaunch.
Allen, who co-founded Microsoft with Bill Gates in 1975, announced in 2011 that he had formed the privately funded Stratolaunch.
The company seeks to cash in on higher demand in coming years for vessels that can put satellites in orbit, competing in the US with other space entrepreneurs such as Elon Musk’s SpaceX and United Launch Alliance - a partnership between Boeing and Lockheed Martin.
Stratolaunch has said it intended to launch its first rockets from the Roc in 2020 at the earliest.
Allen died in October last year while suffering from non-Hodgkins’ lymphoma, just months after the plane’s development was unveiled.
Jody Allen, chair of Vulcan Inc and trustee of the Paul G Allen Trust, said: “The aircraft is a remarkable engineering achievement and we congratulate everyone involved.”