Named Roc, the twin-fuselage aircraft has a wingspan of 385 feet (117 meters). It was developed by Microsoft co-founder Paul G. Allen, who died just months before it flew for the first time in April 2019.
Allen intended to use it as a carrier aircraft for space launches, carrying satellite-laden rockets beneath the center of the wing and releasing them at high altitude.
The new owners initially plan to use it as a carrier aircraft for launches of reusable hypersonic flight research vehicles.
Hypersonic describes flights at speeds of at least Mach 5, or five times the speed of sound.