Seattle-based aerospace company Stratolaunch announced on Sunday that its Roc carrier plane had successfully flown with a fully-fueled-up Talon-A hypersonic vehicle slung under its massive central fuselage for the first time.
“Talon-A’s propulsion system supports a liquid-propellant rocket engine that provides the thrust needed for Talon-A to reach hypersonic speeds. While we have conducted several successful ground tests fueling and igniting the system, we needed to evaluate how the system performs in the flight environment prior to release,” Stratolaunch CEO Zachary Krevor said in a news release.
“Initial results from today’s flight show that the system has performed as predicted, and we will determine our next steps pending the full data review of the test.”
The flight lasted three hours and 22 minutes, during which the Talon-A’s rocket engine "performed as predicted" although still attached to the Roc mothership. It was Stratolaunch’s 12th test of the two aircraft, with its most recent being a drop test in May.
The Roc is the world’s largest still-flying manned aircraft and one of the largest of any type of flying machine ever constructed by humans, sporting a colossal 385-foot wingspan. It has the largest wingspan of any aircraft in history, which is 20 feet longer than a Saturn V rocket was tall, but it is still only about half the length of the massive lighter-than-air dirigibles used for transportation in the late 19th and early 20th centuries, such as the Hindenburg.
The design of the mothership and test vehicle somewhat resemble VirginGalactic’s White Knight Two motherships and the SpaceShipTwo suborbital spaceplane that it hoists for high-altitude launches.
However, such a test would not be the first-ever manned hypersonic vehicle flight: the North American X-15 rocket plane reached Mach 6.7 during a 1967 test flight, which launched from a B-52 Stratofortress carrier plane. In addition, the NASA Space Shuttles regularly reached Mach 25 during atmospheric reentry before the last spaceplane was retired in 2011.
Stratolaunch said it is also pushing ahead on construction of the Talon-2 and Talon-3 vehicles, and that it had signed flight contracts with the US Air Force Research Laboratory and the US Navy’s Multiservice Advanced Capability Test Bed (MACH-TB) program as a subcontractor for Leidos and Dynetics.
The Pentagon has struggled to develop a viable hypersonic weapon or vehicle, having fallen years behind rivals like China and Russia, both of which have multiple Mach 5-plus weapons in service. Because of their speed and maneuverability, hypersonic weapons are nearly impossible to intercept or track using present methods.