Sir Richard Branson's Virgin Orbit is set to conduct its first orbital rocket launch as early as Saturday, in the final test of its Boeing 747 aircraft-based system.
Virgin Orbit's modified aircraft is scheduled to take off from the Mojave Air and Space Port in California at 1 p.m. EDT and fly out over the Pacific Ocean. If all the company's systems are ready, the aircraft will release the LauncherOne rocket, which will then fire its engine and head for space.
The company plans to use the rocket to launch satellites, with the "air launch" system giving a schedule flexibility that Virgin Orbit touts over more common ground-based launch systems like those of SpaceX and Rocket Lab.
Virgin Orbit is a spin-off of Branson's Virgin Galactic space tourism company. While both of the companies launch spacecraft from the air – rather than the ground – that's where the similarities end. Virgin Orbit uses a former commercial jet and will launch satellites the size of refrigerators to orbit, while Virgin Galactic has a one-of-a-kind aircraft and plans to send paying tourists on rides at the edge of space.
Last year the company conducted a drop test of a rocket from the 747, in a final key test before this first launch.
Virgin Orbit told CNBC on Wednesday that last week it conducted a wet dress rehearsal in preparation for this launch, fueling up the rocket and flying with it to verify it's ready.
The company has a four-hour window in which to launch on Saturday, as well as Sunday and Monday. The company has yet to make the final decision on which day it plans to launch, although the back-up launch windows are for similar times of the day.
Once done testing, Virgin Orbit has over a dozen launches lined. Virgin Orbit CEO Dan Hart told CNBC last year that the majority of those launches are for spacecraft from private companies, with only one for NASA and another for the Pentagon's Defense Innovation Unit. But Virgin Orbit has been regularly speaking with the U.S. military about the applications of its technology. Branson met with Air Force leadership last year to discuss Virgin Orbit's capabilities. Following the meeting, Air Force acquisitions head Dr. Will Roper said he was "very excited about small launch," because "if you lose a satellite" you can "put another one up at the time you need it."
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