This week, NASA formally asked the US space industry to dish the details on its plans for brief spaceflights. In essence, the space agency said it wants to buy rides for its astronaut corps and scientists for brief hops into space but needs more information.
The agency was deliberately vague in its solicitation for "suborbital crew transportation services." In a discussion with reporters, the new program manager, Scott Colloredo, said, "We really want to hear what industry has to tell us." He indicated that the solicitation was wide open, with NASA seeking input from established companies such as Blue Origin and Virgin Galactic, to companies such as Space Perspective that want to take people a few dozen kilometers above the Earth's surface.
However, in an interview with Ars, NASA Administrator Jim Bridenstine said the program seeks mostly to increase the time NASA spends in microgravity. "What we’re trying to do is provide access to a resource that historically has been very limited," he said.
NASA has drop towers where experiments can access a couple of seconds of microgravity. During a Zero-G flight, humans and scientific research experience weightlessness in 20-second increments. These are safe and have lower costs. On the other end of the spectrum, through Crew Dragon, NASA astronauts can experience months of microgravity at a cost of more than $50 million per seat and higher exposure to risks.
Finding a sweet spot
Bridenstine said NASA would like to find somewhere in between where there are perhaps 5 to 10 minutes of uninterrupted microgravity. With this amount of time, astronauts might undergo training, scientists could tend to experiments, and engineers could qualify flight hardware.
The timing of the solicitation comes as both Blue Origin, with its New Shepard system, and Virgin Galactic, with its VSS Unity spacecraft, appear to be within a year or less of beginning commercial operations. Although the companies have different systems—New Shepard offers a traditional launch, whereas VSS Unity is a rocket-powered space plane—they both are designed to provide several minutes of weightlessness.
NASA has a number in mind, in terms of budget, that it wants to pay for these services. But Bridenstine said the agency is asking industry for feedback first to get a sense of what private providers are expecting to charge. For the public, Virgin Galactic has sold individual tickets for $250,000. Blue Origin has not set a public price, although it is likely to be higher than this per seat.
Perhaps the biggest question about the program is the risk that NASA is willing to accept in putting its people on these space vehicles. For the space shuttle program, NASA had complete oversight of the vehicle's development. Although the commercial crew program was a public-private partnership, NASA still had significant insight into every facet of SpaceX's Crew Dragon and Boeing's Starliner spacecraft because it paid for most of the development costs.
Balancing cost and risk
Now that NASA is trying to be truly just a customer, how will the agency balance that risk? Bridenstine said he expects to measure safety partly by flight experience. "It’s something that we’re going to have to work through as an agency," he said. "By the time NASA flies on these suborbital commercial vehicles, they will have already flown numerous times. They will not be untested vehicles. NASA has a long history of using flight experience as an alternative to qualifying and certifying every sub-component."
All the same, NASA does ask for detailed safety information about the vehicles in its solicitation. Notably, it seeks data on "fracture control and fault tolerance," indicating a desire to have a fundamental understanding of the structure and margin of these spaceflight systems.
Based upon its overall record, the space shuttle had a loss-of-crew probability of about 1 in 70. Although the commercial crew program is just getting started, NASA required those vehicles to be designed to a loss-of-crew probability of 1 in 270. Asked what standard NASA would hold the suborbital vehicles to, Bridenstine said NASA has not established a stringent value.
However, he said, the probability would be "significantly" less than both the shuttle and commercial crew. "We’re not going to make it more dangerous than orbital flight," he said of suborbital flight.
Managing risks without substantially increasing costs would appear to be a difficult balancing act for NASA when it comes to New Shepard and VSS Unity. However, the fact that two privately funded suborbital launch systems are nearing a state of maturity appears to validate NASA's approach of trying to become one of many customers in spaceflight, rather than the single customer of an expensive launch system.
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June 24, 2020 at 08:29PM
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NASA asks industry to provide it with greater access to microgravity - Ars Technica
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