California-based Stratolaunch, the venture created by the late Microsoft co-founder Paul Allen, released a separation test vehicle for the first time this weekend during an experimental flight of the world’s largest airplane.

The event marked a significant milestone in Stratolaunch’s quest to create an air-launch system for rocket-powered hypersonic vehicles.

Saturday’s outing was the 11th flight test for Stratolaunch’s flying launch pad — a twin-fuselage, six-engine airplane with a record-setting 385-foot wingspan. The plane is nicknamed Roc in honor of a giant bird in Middle East mythology.

Roc carried the Talon-A separation test vehicle, known as TA-0, during three previous test flights. But this was the first time TA-0 was released from Roc’s center-wing pylon to fly free. The release took place during a four-hour, eight-minute flight that involved operations in Vandenberg Space Force Base’s Western Range, off California’s central coast.

“Today’s test was exceptional,” Stratolaunch’s CEO and president, Zachary Krevor, said in a news release. He said the “hardware and data collection systems performed as anticipated, and we now stand at the precipice of achieving hypersonic flight.”

Stratolaunch says it’s planning to launch its rocket-powered, expendable TA-1 hypersonic test vehicle from Roc in late summer. The U.S. Air Force Research Laboratory has signed up to support that test — and Stratolaunch anticipates providing hypersonic test services to AFRL and other customers with future Talon vehicles that will be reusable.

When Allen founded the company in 2011, he envisioned using Roc to send payloads and people into low Earth orbit. After the software billionaire died in 2018, Allen’s estate transferred ownership of Stratolaunch to Cerberus Capital Management, and the company pivoted to focus on hypersonic testing.

We have separation: Stratolaunch reaches milestone with release of test payload

Stratolaunch, the aerospace venture founded by Microsoft co-founder Paul Allen, successfully completed a test flight where it released its Talon-A separation test vehicle (TA-0) from the world’s largest airplane, Roc, for the first time. The flight, conducted at Vandenberg Space Force Base in California, marked a key step toward developing an air-launch system for hypersonic vehicles. The company, now owned by Cerberus Capital Management, plans to launch its rocket-powered TA-1 hypersonic test vehicle in late summer, with support from the U.S. Air Force Research Laboratory for future hypersonic testing services.