The Space Reviewin association with SpaceNews

NASTAR centrifuge
Virgin Galactic is using this centrifuge at the NASTAR Center outside Philadelphia to make sure its customers can handle the accelerations of a SpaceShipTwo flight. (credit: J. Foust)

Screening and training for commercial human spaceflight

Since the beginning of the space age, governments have had their pick of highly-qualified candidates to become astronauts or cosmonauts. With the supply of candidates far exceeding the demand, space agencies have had the luxury of being able to choose the very best, based on both their skills and expertise as well as their physical condition. This was especially true in the early history of spaceflight, when the effects of spaceflight on the human body were relatively unknown, but even today there are strict medical requirements that ensure that astronauts are in the uppermost percentiles of health and fitness among the general population.

As a commercial human spaceflight industry emerges, though, it faces a very different situation. These companies do not typically have the luxury of choosing only a handful of the best, brightest, and fittest people. Indeed, for the business plans of space tourism operators to close, they need to be able to fly as many people with the means to afford such a trip as possible. That means accepting people with a more typical range of health and fitness levels, and with a variety of ailments, while filtering out only those whose conditions are so poor as to be at risk if they flew a suborbital spaceflight. It also means determining a training regimen for both passengers and crewmembers that ensures that they are prepared for the flight without bogging them down with months or years of preparation.


An obstacle for new spaceflight operators is the lack of a large body of medical data that they can refer to regarding how people react to acceleration, weightlessness, and other aspects of spaceflight. Fewer than 500 people have flown in space since Yuri Gagarin’s flight in 1961, and those people were typically in peak health and fitness. “Do we know all the medical risks of flying in space? The answer is we don’t, particularly for people who have medical problems,” said Dr. Melchor Antuñano, director of the Civil Aerospace Medical Institute, at the FAA’s 11th Annual Commercial Space Transportation Conference earlier this month in Crystal City, Virginia. “We have not selected somebody who has had two or three stents, a bypass surgery, who has hepatitis, or who has diabetes.”

“Do we know all the medical risks of flying in space? The answer is we don’t, particularly for people who have medical problems,” said Antuñano.

There is, though, some data finally starting to emerge about how a broader slice of public can tolerate the stresses of launch. Julia Tizard, operations lead for Virgin Galactic, discussed at the conference early results from a passenger training exercise. Virgin has taken a number of its early customers, or Founders, to the NASTAR Center outside Philadelphia for centrifuge training. There, the Founders were put through a centrifuge test that simulated the accelerations they would feel during launch and reentry of a SpaceShipTwo flight.

“If you were working from scratch and guessing what proportion of the market that you would think be able to manage a spaceflight—in the specific context of a Virgin Galactic spaceflight, whose G forces range up to 6 Gs on reentry—you might guess 50 percent,” she said. “At VG, we’re hoping that 80 percent of the people we had sold tickets to would be able to go through the program.”

The results exceeded even Virgin’s hopes. Of the 70 people tested at NASTAR, 93 percent made it through the test successfully. Of the five who did not, she said, two had their training delayed and one their training curtailed, and only two were unable to continue at all. That group of people, she said, ranges in age from 22 to 88, and with varying medical issues, including heart bypass surgery in the last five years.

In the quest for more information about the health issues associated with commercial spaceflight, Antuñano spoke of the need for more people like Greg Olsen, who released details of the medical issues—a black spot that appeared on a lung x-ray—that initially disqualified him from a Soyuz flight to the ISS. Such openness allows the industry to gain experience and evaluate screening criteria, he said, as well as evaluate the use of analog testing environments on the Earth.

Training and regulation

The extensive training that NASA astronauts receive both after their selection to the astronaut corps and when picked for a specific mission, which can last for a year or more, is clearly not appropriate for suborbital spaceflights that will last a matter of hours or even minutes. However, exactly what kind of training is appropriate for such flights is something the industry has not standardized—and, for the time being, does not want to.

Of the 70 Virgin customers tested at NASTAR, 93 percent made it through the centrifuge test successfully.

There are a number of training options available for commercial spaceflight companies. Glenn King, chief operating officer of the NASTAR Center, noted that his facility includes not just the centrifuge used by Virgin Galactic in its recent tests, but also a spatial disorientation trainer and a hypobaric chamber, both useful for preparing passengers and crews for a variety of environments associated with spaceflight.

Some of those environments, such as high-G training, can be provided by aircraft that don’t require the infrastructure and expense of a centrifuge. King argued that, particularly in the event of a medical emergency during a test, a centrifuge—which can be stopped quickly to allow for the rapid egress of an injured person and their transport to a hospital, if needed—was better than an aircraft, which would take time to land and transport a patient to medical care.

Additional training will be required if, as some companies are planning, customers will wear pressure suits during their flight. Jeff Feige, CEO of Orbital Outfitters, a commercial spacesuit developer, said that the training they envision for the use of their suits will range from basic classroom familiarization to simulated pressurization of suit and emergency egress from the vehicle while wearing the suit. Something as simple as testing putting on the suit can be useful for identifying people who have claustrophobia, he said. “A lot of people don’t realize they’re claustrophobic until that helmet is locked and they’re told they can’t take if off. And then all of a sudden they realize they are feeling a little uncomfortable and this isn’t exactly what they had expected.”

Some vehicle developers and operators, though, are concerned about moving too quickly to codify training requirements for crews and customers. “I am living in fear of the move to develop standards for crew and passenger training in this industry,” said Jeff Greason, CEO of XCOR Aerospace. “I think it’s a mistake at this stage in the development of the industry.”

Greason sees three reasons why people might want to move press for standards this early. “The good reason is they want to help,” he said. “But it’s not like we haven’t thought of most of this stuff already.” The bad reasons, he said, were that some people stand to benefit by making training standards, particularly those people who provide similar training services for the government, and that “standards for the sake of standards” are helpful for the industry by making it look more mature. “We don’t know the answers yet,” he said. “Codifying our mistakes early is one of the biggest errors we could make.”

“I am living in fear of the move to develop standards for crew and passenger training in this industry,” said XCOR’s Greason.

Tizard echoed that concern. “The goal obviously here is for a successful long-term business in commercial human spaceflight industry, and that gives us two really key requirements: safety and a booming market, and a booming market requires safety,” she said. “In the early years, it’s important that the operator proposes what those standards and those safety margins are, because they’re the ones with the information about their vehicle’s capabilities and what’s needed to ensure a successful business plan.”

“The learning that we’re doing, and the operational procedures and training procedures that we may apply to our operation may be completely irrelevant to some other vehicle that perhaps doesn’t have the same g-loads or has a completely different cockpit setup,” she added.

At the end of the panel session about training, someone asked what sort of training would be needed for someone who wanted to fly again. “At the coffee table, there’s been discussion about what you do to do when somebody want to fly a second or third time,” said Greason. “If this market is so robust that people get off the plane and they can’t wait to go again, we win.”