Cosmic Girl has been modified to carry a 31-tonne rocket, the Launcher One, under its wing and on the day will take off at around midnight and head out to a point over the Atlantic Ocean off the southwest tip of Ireland.
At this point, it will fly laps in a “racetrack”-shaped flight path while the engineers get the rocket ready for ignition and make the final checks before they give a “go” for launch signal and initiate a 16-minute countdown.
After the countdown, the pilot will detach the rocket from beneath the wing at about 36,000ft, which will freefall for a few seconds before the plane maneuvers away.
Then, the rocket will then ignite and accelerate at up to 22 times the speed of sound, storming south-southwest over the Atlantic before leaving the Earth’s atmosphere and entering into orbit at a staggering speed of 17,200mph. At this point, it will drop off the collection of small satellites as it enters into low-Earth orbit.
Article source: https://www.express.co.uk/news/science/1681932/uk-space-launch-virgin-orbit-spaceport-cornwall-cosmic-girl