Virgin Galactic's manned spaceplane has hit another milestone, breaking Mach 2 as it roared into the mesosphere. With test pilots Dave Mackay and Mike "Sooch" Masucci at the controls, VSS Unity was released from the mothership VMS Eve at an altitude of 46,500 ft (14,200 m) before firing its hybrid rocket engine for 42 seconds to power it to 170,800 ft (32.3 mi, 52 km) and a speed of Mach 2.47 (1,832 mph, 2,948 km/h).

The July 26 morning flight over the Mojave Air and Space Port is the third powered flight in four months of the Unity as Virgin Galactic ramps up to eventual commercial flights to carry passengers and payloads into space on suborbital trajectories before returning to land like a glider. It's also the first flight of the experimental spaceplane to reach the lower reaches of the mesosphere – the region of the atmosphere above the stratosphere ranging from 31 to 62 mi (50 to 100 km).

According to Virgin Galactic, the mesosphere is an under-explored layer of the atmosphere that it hopes to help gather more data on by its flights. In the meantime, the onboard telemetry for the tests continue to record temperature, pressure, humidity, acoustics, thermal response, vibration, acceleration and radiation to better understand the craft and its aerodynamics. In addition, today's flight included a "passenger" in the form of a test dummy.

"It was a thrill from start to finish," Mackay said after the flight. "Unity's rocket motor performed magnificently again and Sooch pulled off a smooth landing. This was a new altitude record for both of us in the cockpit, not to mention our mannequin in the back, and the views of Earth from the black sky were magnificent."

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