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Richard Branson will finally get his space trip on Sunday.

It’s been a very long wait for Mr. Branson, the disrespectful 70-year-old British billionaire who runs a galaxy of Virgin businesses. In 2004, he founded Virgin Galactic to bring adventurous tourists to the edge of space and back in rocket-powered aircraft.

At the time, he thought the commercial service would begin in two to three years. Instead, almost 17 years have passed. Virgin Galactic says there are three more test flights to be done, including the one on Sunday, before it can be ready for paying passengers.

For this flight, Mr. Branson will be a member of the crew. Its job is to evaluate the cabin experience for future customers.

The flight is scheduled to take off on Sunday morning from Spaceport America in New Mexico, about 180 miles south of Albuquerque.

Virgin was expected to air coverage of the flight from 10:30 a.m. Eastern Time, even though the stream hadn’t started 10 minutes after the scheduled time. Video footage broadcast by CNN showed the plane taking off at around 10:40 a.m.

The launch was postponed by about 90 minutes from its original launch time as overnight weather conditions at the spaceport caused the spacecraft to delay its hangar.

Stephen Colbert will host the live stream. The singer Khalid is supposed to perform a new song after the crew has landed. And Mr Branson tweeted a picture that morning with Elon Musk, the founder of SpaceX, who is in New Mexico to see the flight.

The rocket plane, a type called SpaceShipTwo, is about the size of an executive jet. In addition to the two pilots, there are four people in the cabin. This particular SpaceShipTwo is called VSS Unity.

To take off from the ground, Unity is brought to an altitude of approximately 50,000 feet by a larger aircraft. There Unity is released and the engine of the rocket plane is ignited. The acceleration will make people on board feel a force up to 3.5 times their normal weight as they travel to an altitude of more than 80 miles.

At the top of the arch, passengers can get up from their seats and experience apparent weightlessness for about four minutes. Of course, they won’t have escaped gravity. At fifty miles up the earth’s downward gravitational pull is essentially as strong as it is on the ground; rather, the passengers fall at the same speed as the aircraft around them.

Recognition…Virgin Galactic, via Reuters

The two tail booms at the rear of the spacecraft rotate into a “feathered” configuration that creates more drag and stability and allows the aircraft to enter the Earth’s atmosphere more gently. This configuration makes SpaceShipTwo more like a badminton shuttlecock, which always falls with the pointed side down, than an airplane.

Nevertheless, the forces that can be felt on the passengers when descending are greater than when ascending and reach six times the force of gravity.

Once the aircraft is back in the atmosphere, the tail booms rotate back down and the aircraft glides off for a landing. The entire flight can take less than two hours.

Recognition…Virgin Galactic, via Associated Press

The pilots are David Mackay and Michael Masucci.

In addition to Mr. Branson, three Virgin Galactic employees will evaluate what the experience will be like for future paying customers. You are Beth Moses, the lead instructor for the astronauts; Colin Bennett, chief operations engineer; and Sirisha Bandla, vice president of government affairs and research operations.

On Sunday’s flight, Ms. Bandla will conduct an experiment from the University of Florida that looks at how plants react to changing conditions – particularly fluctuations in gravity – in flight during space missions.

The federal government does not impose any regulations on the safety of passengers on a spaceship like Virgin Galactic’s. Unlike commercial passenger aircraft, the rocket aircraft has not been certified by the Federal Aviation Administration. In fact, the FAA is legally prohibited from making such requirements until 2023.

The rationale is that emerging aerospace companies like Virgin Galactic need a “learning curve” to try out designs and processes, and that too much regulation too soon would stifle innovations that would lead to better, more efficient designs.

Future passengers have to sign forms in which the “informed consent” to the risks is confirmed, similar to parachuting or bungee jumping.

What the FAA regulates is ensuring the safety of people who are not on the plane – that is, if something goes wrong, the risk to the “innocent public” on the ground is tiny.

Recognition…Henry A. Barrios / The Bakersfield Californian, via Associated Press

Virgin Galactic’s design already has an imperfect safety record. The company’s first spaceplane, the VSS Enterprise, crashed during a test flight in 2014 when the co-pilot moved a lever too early in flight, which allowed the tail booms to rotate if they were supposed to stay rigid. The Enterprise broke apart and co-pilot Michael Alsbury was killed. The pilot Peter Siebold survived the parachute jump from the plane.

The controls have been redesigned so that the tail boom cannot be unlocked prematurely.

In 2019, Virgin Galactic came close to yet another catastrophe when a new metal thermal sheet was improperly installed, covering holes that allow air trapped in a horizontal stabilizer – the small horizontal wing on the tail of an aircraft – to be removed when the aircraft emanating from it rises into the thinned layers of the atmosphere. Instead, the pressure of the trapped air ripped a seal along one of the stabilizers.

The mishap was revealed earlier this year in the book “Test Gods” by Nicholas Schmidle, an employee of the New Yorker. The book quotes Todd Ericson, then vice president of security and testing for Virgin Galactic, as saying, “I don’t know how we didn’t lose the vehicle and killed three people.”

Recognition…Joe Skipper / Reuters

Starting a space exploration company was perhaps an unsurprising move for Mr. Branson, who has made a career – and an estimated $ 6 billion fortune – and built eye-catching, up-and-coming businesses that he promotes with the flair of a showman.

What became his Virgin business empire began with a small record store in central London in the 1970s before Mr. Branson moved it to Virgin Records, home to acts like the Sex Pistols, Peter Gabriel and others. In 1984 he co-founded Virgin Atlantic to challenge British Airways in long-haul passenger air travel. Other Virgin-branded airlines followed suit.

The Virgin Group also expanded into other businesses, including a wireless operator, passenger railroad, and hotel chain. Not all of them worked flawlessly: Both Virgin Atlantic and Virgin Australia filed for bankruptcy during the pandemic last year, while today few remember its ventures in the soft drinks, cosmetics or lingerie sectors.

Virgin Galactic was announced with great roar in 2004 with the promise of creating a space tourism company in style. Virgin Orbit, a spin-off from that company that launches small satellites from a jumbo jet, launched 13 years later. Virgin Orbit, now separate from Virgin Galactic, has launched payloads into orbit twice this year.

The space tourism company is well connected to Mr. Branson’s penchant for high-flying activities such as skydiving and hot air balloon rides. And unlike many of the Virgin Group’s businesses, which are actually minority interests or simply licensees, Virgin Galactic has been a primary focus of Mr. Branson. He raised a billion dollars for the Saudi Arabian space company only to break the deal in 2018 after the murder of dissident journalist Jamal Khashoggi. And in a government filing, the company said it had “benefited from its” personal network to generate new inquiries and reservation sales, as well as referrals from existing reservation holders. “

“We worked on our space program for 14 years,” Branson said in a 2018 Bloomberg Television interview. “And it’s been tough, and space is tough – it’s rocket science.” He added that he was hoping to be able to travel on one of Virgin Galactic’s flights by the end of the year.

Virgin Galactic joined the New York Stock Exchange in 2019 after merging one of the company’s flight suits with a publicly traded mutual fund.

But while Virgin Galactic has been trying to keep up with the likes of Mr. Bezos’ Blue Origin, Mr. Branson has downplayed any rivalry between the two. “I know no one will believe me if I say it, but honestly it doesn’t exist,” he told The Today Show earlier this week.

More than 600 people have registered for flights. Virgin Galactic originally charged $ 200,000 per seat and then raised the price to $ 250,000 before ceasing sales after the 2014 crash. The company hasn’t said what it will charge when it resumes sales, but the cost is expected to be higher.

Virgin Galactic’s aircraft conducted science experiments during previous test flights. For example, a scientist from the University of Florida tested imaging technologies that record the reaction of plants – whose genes are switched on and off – to the stress of space travel.

In the future, scientists will be able to accompany their experiments. On this flight, Ms. Bandla of Virgin Galactic will conduct an experiment that involves handling multiple tubes during the trip.

The Italian Air Force has bought seats on future flights for scientific research, as has the Southwest Research Institute in Boulder, Colorado. Flying experiments on suborbital flights will be much easier, faster and cheaper than bringing them to the International Space Station.

VSS Unity was parked on the runway on Sunday morning before the flight.Recognition…Joe Skipper / Reuters

The United States Air Force and the Federal Aviation Administration set the limit of space at 80 miles. The FAA has granted astronaut wings to Virgin Galactic crew members who have flown on previous test flights.

Internationally, however, the altitude that marks the beginning of space is usually set at 100 kilometers, or just over 62 miles, called the Karman Line.

SpaceShipTwo was originally supposed to rise above the 62 mile altitude, but difficulties developing the engine resulted in a less powerful, but more reliable, design that couldn’t propel the spaceship that high.