Teams preparing for the UK’s first orbital rocket launch were “excited” but “very sharp” when it came to final checks, the mission chief said.
The Start Me Up mission departs from Spaceport Cornwall at Newquay Airport, with the launch window now starting at around 9.40pm on Monday.
It will be the first launch from orbit in the UK mainland – or anywhere in Western Europe – and comes after technical problems delayed it from just before Christmas.
“Space launches are a very serious business, and we’re going to look at integrating all the information about systems, weather and range,” said Virgin Orbit boss Dan Hart.
However, there won’t be the flare and noise of a NASA launch.
Instead, a modified Boeing 747 called Cosmic Girl will carry a 21-meter-long LaucherOne rocket (which contains many small satellites) to 35,000 feet before launching into space and eventually reaching 8,000 miles per hour.
It will happen about an hour after takeoff, and the event will be broadcast live online.
Mr Hart said on Sunday afternoon that “everything is green at the moment” for the launch.
However, he added that they are “exercising caution” and are prepared to delay if necessary because of other launch opportunities in the coming weeks.
“The rocket was armed yesterday [Saturday] We will be loading fuel later today. So we’re going all out now,” he told reporters.
Since the rocket is mounted under the wing of the plane, he said crosswinds are something they need to keep an eye on.
Satellites on board include prototype track factory Used to make high-value alloys and semiconductors, and a satellite to join a satellite constellation to monitor illegal fishing, smuggling, trafficking, piracy and terrorism.
Melissa Thorpe, head of Spaceport Cornwall, said the team involved had “completely smashed it” and she was confident ahead of the big day.
“I’m so excited…I can’t wait for the UK to join this exclusive launch club because it feels so good,” she said.
Mr Hart said once the rocket was launched, it would be relatively quick to get the satellite into orbit.
“We’ll do a three-minute first stage burn, then a second stage burn of about six minutes. We’ll go around Antarctica, come up near Australia, and then we’ll watch the final burn and payload deployment.”
He said “everything needs to be done right” for the mission to work.
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spaceport cornwall is Get licensed in the UK firstbut there could be more in the coming years as corporate demand for launching small satellites increases.
“The UK has identified seven other spaceports for vertical and horizontal launches,” said UK Space Agency deputy chief executive Ian Annette.
He said Snowdonia in North Wales and Glasgow Prestwick Airport were among them and local authorities were looking at those opportunities.
Ms Thorpe said Newquay had undergone some “future-proof” changes to enable it to double as a spaceport, including strengthening taxiways and turning aprons to ensure Virgin Orbit planes were easier to maneuver.
“We can open up to other companies when Virgin is not here,” she said.
“We’ve got a whole new facility opening where other space companies are going to open — it’s full, we haven’t even opened yet. That’s how excited people are.”