Stratolaunch, the air-launch company founded by the late Seattle software billionaire Paul Allen, today conducted its second captive-carry test flight with the world’s largest airplane and a piggyback payload. The six-hour outing from California’s Mojave Air and Space Port marked further progress toward the first launch of the Talon-A hypersonic flight vehicle.

Today’s flight gave Stratolaunch’s team a chance to rehearse procedures for releasing a separation test vehicle from the 385-foot-wide Roc aircraft in midflight — and eventually launching rocket-powered Talon-A vehicles for government and commercial applications. “We are excited for what’s ahead this year as we bring out hypersonic flight test service online for our customers and the nation,” Stratolaunch CEO Zachary Krevor said in a news release.

Allen’s holding company, Vulcan Inc., transferred ownership of Stratolaunch to Cerberus Capital Management in 2019.

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