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A final defense of Constellation
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A final defense of Constellation
NASA admininstrator Mike Griffin speaks about the agency’s exploration architecture in a January 8 Space Transportation Association speech in Washington. (credit: J. Foust)
by Jeff Foust Whether his tenure as NASA administrator ends next week or next year (and these days it’s looking more like the former than the latter), Mike Griffin will be remembered primarily for his role in developing and implementing the architecture of spacecraft and launch vehicles collectively known as Constellation. When Griffin took office in April of 2005, more than a year had elapsed since President Bush’s declaration of the Vision for Space Exploration but there was still no clear idea of how NASA would carry out that plan. Five months later, though, NASA completed the Exploration Systems Architecture Study (ESAS) and declared what that system would be: a largely shuttle-derived pair of launch vehicles that would send a scaled-up Apollo-like capsule and lander to the Moon. That decision wasn’t that surprising to many since Griffin had co-chaired a Planetary Society study the previous year that endorsed a similar approach (see “CEV: a different approach”, The Space Review, September 13, 2004). Since then, NASA has made steady progress with Constellation, letting contracts for all the elements of the Ares 1 launch vehicle and Orion spacecraft, and more recently beginning the early stages of the same process with the Ares 5 heavy-lift launcher and Altair lunar lander. However, Constellation has not been without its critics. Some raise technical concerns about the current system, particularly the Ares 1, while others argue that alternative architectures would be faster, less expensive, and/or safer than the current approach (see “Staying the course in a sea of change”, The Space Review, December 22, 2008). And, if anything, this drumbeat of criticism has gotten louder, not softer, in the last year. Given this atmosphere, it’s not surprising that Griffin spent much—nearly all, effectively—of his speech at a Space Transportation Association (STA) breakfast on Capitol Hill on January 8 defending Constellation against the various alternatives that have been proposed to replace it. It’s not the first time Griffin has done this, even to the same audience: he spent much a speech nearly a year ago on the same topic (see“Defending Constellation”, The Space Review, February 4, 2008), something he noted with a bit of frustration. “From all the questions that are still out there, I guess I didn’t do a very good job,” he said in his opening remarks. However, this time there was a palpable sense that this was perhaps the last time Griffin would have a chance to discuss Constellation as NASA administrator, even as the program faces an uncertain future in the next administration. Constellation versus the worldAfter some introductory remarks about the Vision and Constellation, Griffin turned his attention to a number of alternatives that have been proposed. The key theme he identified in these alternatives is that they left out or changed some of the requirements that Constellation had to meet. “Many of the suggestions offered to me with the intent of improving Constellation take this form,” he said. “The offerer neglects a particular requirement that is disliked, and with that omission is able to provide an improved approach for the goals which remain.” “Exactly what is it that makes the EELV industrial base more important to support than the shuttle industrial base?” Griffin asked. “Why is it, exactly, that in this time of transition in NASA, in our spaceflight systems, we ought to be making decisions to augment the existing Atlas and Delta workforce, while completely decimating the shuttle workforce?” Griffin first looked at one of the most common alternatives: replacing Ares 1 with either an existing EELV—some version of the Atlas 5 or Delta 4—or a new variant. The problem with using an existing EELV, Griffin claimed, is that it would not be able to launch the larger “lunar-capable” Orion spacecraft, only a scaled-down version best suited for low Earth orbit (LEO) operations. If an EELV is modified to launch the existing Orion, he added, it would require modifications to its first stage to allow it to launch heavier payloads, as well as a new human-rated second stage—exactly what NASA is doing with the Ares 1. “Why is this a good thing to do with EELV and a bad thing to do with Ares?” Griffin also said that a NASA probabilistic risk assessment found that Ares 1 would be twice as safe as an EELV-derived vehicle, a difference he said “is ignored by almost everyone suggesting that we make a change” even though it played a major factor in NASA’s decision to go with the shuttle-derived architecture. “I cannot responsibly ignore it, for reasons having nothing to do with money,” he said. For those focused only on money, though, he noted that one additional accident of a hypothetical lower-cost alternative system would wipe out any cost savings it would offer. And for those who argue that a switch to an EELV-based system would give the struggling US launch industry some much-needed support, Griffin effectively said he had no reason to favor the EELV part of the industry over the shuttle part. “Exactly what is it that makes the EELV industrial base more important to support than the shuttle industrial base?” he asked. “Why is it, exactly, that in this time of transition in NASA, in our spaceflight systems, we ought to be making decisions to augment the existing Atlas and Delta workforce, while completely decimating the shuttle workforce? Why is that?” Another alternative being floated is that NASA not design Ares 1 and Orion for LEO operations, allowing them to be optimized for lunar missions while turning over human access to LEO to the commercial sector. While Griffin has been a strong supporter of efforts like COTS and the recently-awarded commercial cargo resupply contracts, he sounded skeptical about depending on the commercial sector to have a crew transportation system ready in the foreseeable future. “All I can say about this is, if you like the present gap in US government access to LEO, you’ll love this one.” Besides providing a backup for the uncertain development schedules of commercial vehicles, Griffin said that a government system that can access the ISS can also act “as a control on the price” the government is willing to pay for commercial systems as well as alternatives offered by international partners. He also suggested that a government system might be more flexible and robust for LEO operations than a commercial system optimized for ISS transportation. “Do you want to do another Hubble servicing mission, or something else like it? Do you want to do something else in the future that you haven’t thought of today?” he asked. “If so, you’re going to need something more than basic commercial transportation.” A related alternative is to keep the shuttle flying until a commercial crewed system is ready, thus eliminating any gap in US human spaceflight capabilities. While Griffin, as before, expressed his desire not to rely solely on commercial systems for LEO access, he offered a more nuanced answer on extending the life of the shuttle. A recent NASA study found that it would cost $3 billion a year to fly two shuttle missions a year from 2011 to 2015 to service the ISS. “As an engineer and program manager, my immediate thought is that I’ve got better uses for $3 billion a year than flying the shuttle to reduce, but not eliminate, dependence upon Soyuz,” he said. While he reiterated it was “unwise” for the US to be reliant on another nation for access to ISS, he said he was willing to accept it for a few years so that NASA can develop Constellation. Stepping back to look at the big picture, though, Griffin offered a somewhat different opinion. “One could argue that America’s international standing will suffer as a result of our demonstrated inability to provide transportation to the space station we built,” he said. “Is it worth $3 billion a year, and the risk of additional Shuttle flights, to prevent this loss of stature, image, and clear preeminence in spaceflight? It might be.” While Griffin has been a supporter of COTS, he sounded skeptical about depending on the commercial sector to have a crew transportation system ready in the foreseeable future. “All I can say about this is, if you like the present gap in US government access to LEO, you’ll love this one.” He said that he could support such a decision to extend the shuttle’s life, provided those in the “highest levels of government” who made that decision understood the risks involved with flying the shuttle: about a one-in-eight chance of the loss of the crew in those ten additional flights. However, such an extension would have to be made with additional funding, not the reprogramming of existing NASA budgets, which Griffin said would only delay the gap, not eliminate it. “In the bluntest of terms, preserving our nation’s preeminence in space by eliminating the gap might be worth $3 billion a year and the attendant risk of life. Spending that money and taking those risks to postpone a gap, is not.” Later, in a question-and-answer session following his speech, Griffin said that if such extra money became available, spending it all on extending the shuttle might not be the best option, given that the money could also be applied to accelerating Constellation. “NASA has never been asked the question of how you would do it if the goal were to be not to have a gap in US human spaceflight,” he said. “What combination of shuttle extension, international dependence, and acceleration of Constellation would you use to prevent a gap in US human spaceflight?” Griffin also addressed one other alternative, where the Ares 1 is cancelled and dual Ares 5 launches are used for lunar missions. That approach would allow for 69 percent more payload to the Moon at a cost increase of only 32 percent per mission, and Griffin added that nothing in the Ares 5 design would preclude allowing it to be human-rated is desired. However, he said the Ares 1/Ares 5 approach currently planned would be more cost-effective overall. Most alternatives to the current system still call for the development of the Ares 5 for lunar missions, yet many of the elements of Ares 5 would also be used in Ares 1, from the solid rocket booster segments and J-2X upper-stage engine to flight control systems. “Given that we have to develop Ares 5 for the lunar mission and, later, Mars, the additional development cost for Ares 1 is $2.7 billion,” he said, a point he felt was so important he repeated it. “If you commit to lunar exploration and beyond with Ares 5, then for an additional $2.7 billion you also get the new human-rated crew transportation system mandated by the Columbia Accident Investigation Board.” Griffin’s last stand?While he did not explicitly address it in his speech, many in attendance treated the event as one of Griffin’s last major addresses as NASA administrator and a final defense of Constellation. There is growing belief that Griffin will not be retained by the Obama administration, even for a short period. With the inauguration just over a week away, that would effectively make this week Griffin’s last as administrator. Some, though, are still hoping that Griffin will be kept on. “He’s reinvigorated the human spaceflight program,” said Congressman Ralph Hall (R-TX), ranking member of the House Science and Technology Committee, in remarks introducing Griffin. “I’m very hopeful he’s going to be retained. [Committee chairman] Bart [Gordon] has recommended him, and I’ve recommended him.” Hall added he wrote a congratulatory note to President-elect Obama after the election, which Obama responded to with a call. While Hall wasn’t in the office when the call came, he said he hoped to connect with Obama at some point, suggesting he would bring up Griffin’s status in that conversation. “How do you turn it into a negative?” Griffin said of Horowitz’s petition. “Why did we all in the Washington community cringe when that came out? Because we in the Washington community are all so damn cynical that we knew that something like that will backfire.” Griffin has also been the subject of some unusual lobbying efforts, including an online petition organized by former astronaut Scott “Doc” Horowitz last month. That petition has garnered nearly 3,000 “signatures” since its release, ranging from astronauts and other NASA employees to members of the general public and even “anonymous” signatures. The petition got additional attention when Griffin’s wife sent out an email to her contacts asking them to sign the petition. Asked about the petition after his speech, Griffin went through a mix of emotions. “I was embarrassed, of course, when it was conveyed to my attention,” he said, but also said he was “very honored” that Horowitz—who Griffin described as a “national hero” for being an astronaut—would do it. He noted, though, that the petition generated some negative reaction. “How do you turn it into a negative?” he asked. “Why did we all in the Washington community cringe when that came out? Because we in the Washington community are all so damn cynical that we knew that something like that will backfire… So how do we get to a place in Washington where somebody doing something nice for you is viewed as ammunition for your enemies? How does that happen?” If Griffin’s tenure is near an end, who might replace him? The list of candidates is a long one, and got even longer last week. On Tuesday came word that former astronaut Charles Bolden had emerged as a leading candidate to replace Griffin. It would not be the first time Bolden had been considered for a leading NASA position: in 2002 he was nominated to become deputy administrator shortly after Sean O’Keefe became administrator. However, the nomination was withdrawn after some opposition to having an active-duty military officer—Bolden was a major general in the Marine Corps, but has since retired—serving in a civilian position during a time of war. Bolden, at least publicly, said he had not been touch with Obama’s transition team about the post. “The only comment on that story I can offer you is that nobody has talked to me in an official capacity,” he responded during a previously-scheduled webcast organized by the Conrad Foundation on January 6. “I have not visited with the transition team or anybody from the Obama administration. I’m incredibly honored that my name would be floated around but those are things I haven’t been approached about yet so I can’t offer you an opinion or anything.” Later in the week, Space News reported that Charles Kennel, a former director of the Scripps Institution of Oceanography and chair of the Space Studies Board of the National Academies, was now under consideration to lead NASA. Kennel had served at NASA in the mid-1990s as associate administrator for the agency’s Earth sciences program, then known as “Mission to Planet Earth”. He later served on the NASA Advisory Council (NAC) from 1998 to 2006, including a stint as chair of the council from 2001 and 2005. He abruptly resigned from the NAC in August 2006 at the same time two other members, also scientists, were asked to leave. According to the Space News report, the Obama transition team is interested in having a “distinguished scientist” lead NASA, just as it did with its picks for Secretary of Energy and presidential science advisor. The two Charleses may offer very different futures for NASA in general and Constellation in particular. Bolden, after his retirement from the Marines, did some lobbying work for ATK, a company that has strongly supported the current exploration architecture. On the other hand, some worry that the selection of a scientist like Kennel might mean a retrenchment in Constellation or human spaceflight in general. In any case, the administration’s selection of Griffin’s replacement could be the first clear sign of what direction they will go in space—and just how effective Griffin’s staunch defense of NASA’s exploration architecture was.
Source: http://www.thespacereview.com/article/1285/1
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