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Can the lessons painfully learned from the shuttle program be applied to the crop of new human spaceflight vehicles under development today? (credit: SNC)

A tragedy’s lessons for the future


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A milestone anniversary is an opportunity to look back and reflect and remember—and, in the case of a tragedy, also to mourn. That was certainly the case earlier this month at a day-long symposium at George Washington University (GWU) in Washington, DC. The March 8th event, titled “Columbia+10: Lessons Learned and Unlearned” and organized by the university’s Space Policy Institute and the American Institute of Aeronautics and Astronautics (AIAA), brought together some of the key people involved in the investigation of, and recovery from, the Columbia accident 10 years ago last month (see “Community, lenses, and learning: the ‘Columbia+10’ workshop”, The Space Review, March 11, 2013).

There is now both a technological and programmatic diversity of human spaceflight programs never before seen in the space agency’s history.

However, as the symposium’s title suggests, the anniversary is also an opportunity to examine the lessons of the accident—those not just involving the specific technological causes of the loss of Columbia, but the policy and cultural issues as well. Those latter lessons are, in the long run, arguably more important than the technical ones, for they transcend the specific fixes applied to the now-retired Space Shuttle. Can those lessons survive the transition from the shuttle to the vehicles under development now, by both NASA and the private sector, to transport astronauts into orbit and beyond in the next decade?

In the short term, at least, those lessons were heeded, as demonstrated by the successful return to flight of the Space Shuttle and the safe return of the crews of the program’s remaining missions, through STS-135 in July 2011. Admiral Harold Gehman, who chaired the Columbia Accident Investigation Board (CAIB), noted in a talk at the end of the symposium that he saw the lessons of the accident, and the recommendations in the board’s final report, in use when foam struck Discovery during launch on the return-to-flight mission, STS-114, in July 2005. Unlike with Columbia, there was plenty of images and other information about the foam strike, and an on-orbit inspection confirmed there was no damage to the orbiter. “Don’t you think I felt good about that? Yes, I did,” he said.

However, the future of NASA’s human spaceflight program is very different from even its recent past. The shuttle-specific findings and recommendations of the CAIB report are now of primarily historical relevance: it’s unlikely than anything even vaguely similar to the Space Shuttle will fly in the foreseeable future, and thus not vulnerable to the same failure modes that doomed Columbia.

More importantly, though, there is both a technological and programmatic diversity of human spaceflight programs never before seen in the space agency’s history. Until recently, the operation of human spaceflight programs had been a sequential process: Mercury, Gemini, Apollo, and the Space Shuttle. While the development of these vehicles overlapped, they were flown in sequence.

The future, by contrast, looks to be far more parallel than serial. NASA is developing its own crewed vehicle, Orion, as well as a rocket, the Space Launch System (SLS), to launch it on missions beyond Earth orbit. At the same time, though, NASA is also supporting, technically and financially, the development of several commercial crew vehicles designed to carry NASA astronauts to the International Space Station (ISS), among other applications. Three companies—Boeing, Sierra Nevada, and SpaceX—are currently funded to work on vehicle concepts, while a fourth, Blue Origin, is continuing development through an unfunded extension of an earlier funded agreement with NASA. Add in work in the private sector on crewed suborbital vehicles, like Virgin Galactic’s SpaceShipTwo and XCOR Aerospace’s Lynx, and it’s clear that today features a far more dynamic environment for human spaceflight than at any point in the history of the Space Age, even with the current gap in US human access to low Earth orbit.

But is this dynamic environment also a safe one? During the GWU symposium, some expressed concerns that have been debated in the last couple of years about the safety of commercial crew systems in general, given the nature of how NASA is funding those efforts. Under the Space Act Agreements that have funded commercial crew development efforts to date, NASA cannot require companies to follow specific guidelines such as human rating requirements. It is, of course, in those companies’ best interests to comply with those requirements if they want future business from NASA under contracts that will require adherence to such requirements, but the current situation leaves some concerned.

“With a Space Act Agreement, you can’t impose requirements,” said Doug Cooke, former associate administrator for exploration at NASA. “Yet the safety process in a program goes on on a daily basis.” Design decisions in any program are made every day, he said, with implications for safety.

“What’s the purpose of commercial space?” Dyer asked. “Is it transportation to low Earth orbit… or is it to develop an industry?”

NASA has addressed this by issuing separate contracts (as opposed to Space Act Agreements) to the three currently-funded commercial crew companies to develop certification plans for their spacecraft to ensure their ability to safely transport astronauts to and from the ISS. “But it comes late in the process, and a lot of the design has already happened,” said Cooke. “Are we early enough in the process to have the confidence in the systems that we’re developing?”

Vice Admiral Joseph Dyer, chairman of the Aerospace Safety Advisory Panel (ASAP), said the recent certification contracts eased some his earlier concerns. “We pressed hard on how do you certify and how do you communicate certification,” he said, and saw the certification contracts as a sign of progress on that. However, he said ASAP has “hair on the back of their necks standing up” over optional milestones in the latest Space Act Agreements that include crewed test flights, presumably because such flights might have lower levels of oversight than a typical NASA crewed mission. “We’re a little suspect of what might go on in this optional milestone as we look at budget pressures coming downstream.”

Dyer devoted a significant portion of his keynote talk at the symposium to commercial crew, going beyond the certification and related safety concerns discussed above, something ASAP also examined in detail in its latest annual report. He expressed some skepticism that there is a commercial market for the vehicles being developed beyond NASA’s own ISS transportation requirements. “I wonder how many ‘one-percenters’ there are with the willingness to go and pay for a ride in space,” he said of space tourism, one potential non-government market. (Past studies not mentioned by Dyer, including NASA’s own commercial market assessment, have suggested a market demand of single digit to dozens per year; seven people have already paid for such flights, with one person going twice.)

That focus on commercial crew by Dyer was part of an examination of its purpose. “What’s the purpose of commercial space?” he asked. “Is it transportation to low Earth orbit… or is it to develop an industry?” He said the commercial crew program was being asked to do both, which could compromise safety. “If all you’re doing is economic development, feel free to be capricious, stretch, innovate, try new things. If you really have to haul humans to space, then you have a different responsibility and, one would hope, a different attitude.”

By comparison, NASA’s SLS and Orion programs got little attention during the day with regards to safety. However, both traditional government-run programs and newer commercial-led efforts face a shared concern raised during the symposium: how safe should human spaceflight be?

“It was much safer to fly in combat than to climb on the Space Shuttle,” Rominger said.

Safer than the shuttle, at a bare minimum, which suffered two fatal accidents in its 135 missions. Former astronaut Scott Horowitz recalled that, after the Columbia accident, the Astronaut Office published a memo on crew safety that concluded that future systems should have an abort system and a “survivability” of 0.999; that is, a 1-in-1,000 chance of a fatal accident. “The goal was that the orbiter was on the order of 1-in-100,” he said, “and an order of magnitude improvement, after 40 years of spaceflight, would be on the order in 1-in-1,000.”

Kent Rominger, chief of the Astronaut Office at the time of the Columbia accident, said that “emotions were kind of all over the map” in the first meeting of the astronaut corps after the accident: some veteran astronauts felt that the shuttle was perhaps too risky to high, while those who had yet to fly “didn’t care that the shuttle was risky,” he recalled. That led to the Astronaut Office memo on crew safety.

However, Rominger noted that even that higher threshold for safety still meant that spaceflight was quite risky. “When I flew combat in Desert Storm, when I shot off the front of the Nimitz in my trusty Tomcat, my chances were not coming back—actually, my chances of getting killed—were 1-in-20,000,” he said. “It was much safer to fly in combat than to climb on the Space Shuttle.”

That 1-in-1,000 figure has driven requirements for future programs, both government and commercial. Dyer, though, cautioned against some proposals to start at a lower loss-of-crew threshold and work to improve it over time. Past experience with aerospace programs, he said, shows a relationship between cost and safety that is front-loaded. “By the time you’ve spent 10 percent of your money, you have preordained 85 percent of the cost, and I would say safety, of the resultant system,” he said.

While a vehicle with a 1-in-1,000 risk of a fatal accident would be a significant improvement over any previous human spaceflight system, there is still debate over whether that is safe enough in a society that many perceive is far more risk averse than decades past. “Are we today at NASA, and are we as a nation, too risk averse? I think so,” Dyer said, but added that the ASAP membership was open to accepting additional risk in spaceflight if the risks—and rewards—were understood. “We are supportive of accepting more risk if we recognize it as what it is and the rewards that are associated with it.”

Rominger suggested the high visibility of human spaceflight is a key factor that drives the need for higher safety. “You lose a national asset and seven astronauts, our whole nation takes a hit in prestige,” he said. “It appears that the further we go along, the less that, as Americans, we’re willing to accept that. So if you want a healthy spaceflight program, you have got to have one that doesn’t lose the crew.”

“In exploration, safety is not the most important thing,” Hale said. “In exploration, the most important thing is to actually go.”

That attitude seems to contrast with last month’s rollout of Inspiration Mars, a private effort to fly a two-person Mars flyby mission in 2018 (see “A Martian adventure for inspiration, not commercialization”, The Space Review, March 4, 2013). One of the key rationales for the mission, backers argued, was to demonstrate a willingness to take risks. “We could get America back to taking those kinds of risks that really push the boundaries and inspire people to greatness,” Taber MacCallum, the CEO of Paragon Space Development Systems and one of the key people involved in Inspiration Mars, said at the time.

“If we wanted a certain guarantee [of safety] we wouldn’t do this,” Jonathan Clark said at the February 27 press conference announcing Inspiration Mars. Yet, moments later, Dennis Tito, the founder and initial financial backer of the project, suggested there was, if not a guarantee of safety, a relatively high bar for the mission to clear in that regard. “I would not be comfortable launching this mission with anything other than a .99 probability of the crew returning safely,” he said, a level of safety higher than the demonstrated flight record of the shuttle.

The challenge of balancing risk versus reward, and understanding exactly what the risks are, continues. In comments at the end of the symposium, former shuttle program manager Wayne Hale saw signs of progress at NASA as the agency incorporated the lessons of the Columbia accident. “The work isn’t done because we have a new generation to educate who didn’t live through this,” he said of the experience of the Columbia accident.

“Make the risk as small as you possibly can, then go forward,” he advised. “In exploration, safety is not the most important thing. In exploration, the most important thing is to actually go.”


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