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Projects like the X-37B (above) and the Dragon capsule have demonstrated the ability recover and reuse spacceraft; the same is now needed for launch vehicles. (credit: USAF)

Taking the initiative: SLI and the next generation

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Two events occurring within a week in December 2010 highlight a curious dichotomy in American space progress. One company, SpaceX, returned its Dragon reusable capsule from orbit, a first-ever achievement for a private company. That took place five days after the Air Force returned the Boeing-built X-37B reusable unmanned mini-shuttle from orbit. The two events mark significant achievements in different approaches to recovering orbital spacecraft. The apparent disconnect lies not in the capsule-versus-wings approach to recovery, but rather in the fact that both reusable orbital craft are launched by what are currently non-reusable launch vehicles.

In an era suffused with the dictum “Reduce, Reuse, Recycle,” declining to recover a perfectly good rocket the first time the fuel gauge reads “E” is a strange thing at the very least.

They are not alone. In addition to the fuzzy-purposed NASA-funded Orion Crew Exploration Vehicle being built by Lockheed Martin, Boeing introduced its reusable CST-100 crew capsule in 2010 as well. In an encouraging sign, the near future of human spaceflight is not limited to just capsules: both Orbital Sciences Corporation and Sierra Nevada Corporation introduced crew vehicle concepts based on the NASA HL-20 lifting body design. All—except possibly Orion—will be competing for NASA Commercial Crew Development 2 (CCDev-2) design contracts to fly astronauts to the International Space Station. They are all also candidates for whatever alternate applications may develop. Taken as a whole, these proposals suggest that US aerospace companies are making definitive strides in developing and operating reusable orbital spacecraft. If only similar progress was being made in the vehicles which launch them, though.

In an era suffused with the dictum “Reduce, Reuse, Recycle,” declining to recover a perfectly good rocket the first time the fuel gauge reads “E” is a strange thing at the very least, and more than a little tacky. It is also a spectacular waste of money, resources, and opportunity. The stranger thing is, outside Elon Musk’s assertions that SpaceX expects to begin recovering the Falcon 9 first stage by its sixth flight, no one else is even trying. This might be understandable if the price of expendable rockets was going dramatically down rather than up. More curiously, in their own words, some of the same contractors have plainly stated that the means to enable first stage recovery and reuse have been available for 40 years.

With the notable exception of Falcon 9/Dragon or possible Falcon 9/CST-100 combinations, each of the proposed reusable crew vehicles is to be launched by a United Launch Alliance (ULA) Atlas V or Delta IV expendable rocket. While the Boeing-heritage Delta IV is powered by an expendable engine, the Atlas V, originally developed by Lockheed Martin, is powered by a reusable engine, the Russian RD-180. Despite this fact ULA feels no need to actively undertake recovery efforts.

The most recent entry into the booster field, the proposed ATK/EADS Astrium Liberty rocket, based on the Ares I, is, like the shuttle’s Solid Rocket Booster, is not so much reused as remanufactured. Nevertheless, in introducing the proposal, ATK noted the Liberty would offer some savings over the Atlas V, and would fly for less than $180 million per launch. As a sales pitch, this says more about the problem with expendables in general than it does about the benefits of any specific platform.

Even so, compared to estimates of shuttle launch costs, the eventual winners of the commercial crew competition should offer significant savings in terms of crew transport costs, albeit at an irreplaceable loss of capability. (As an aside, contrary to the terminology the press routinely uses, none of the systems discussed can “replace” the shuttle, only assume some of its duties.) When considering all of the lost functionality, however, one could almost reach the conclusion that, compared to some fully expendable rockets, the shuttle is not as overpriced as it might seem at first.

Without much deeper price reductions, which can only come from some form of reusability, an expanded commercial market in low Earth orbit remains very much in question.

While the market for publically-funded commercial crew transport to ISS is clearly limited, it is becoming increasingly certain. NASA Administrator Charles Bolden’s emphatic declaration in support of commercial crew may well signify a bellwether date in space history (see “Commercial crew and NASA’s tipping point”, The Space Review, February 14, 2011). The most significant implication may be that other opportunities for leveraging the spacecraft initially offered for ISS cargo and crew duties can begin to emerge in earnest. One of the most promising is Bigelow Aerospace’s proposed space stations, which anticipate using the CST-100 for crew transfer. Boeing announced on February 9th that it is also considering marketing the CST-100 for other national launchers. The fact that several of the proposed crew transport craft are promoted as being able to launch on more than one rocket indicates an encouraging shift in the way some aerospace companies are approaching the marketplace. It is something more akin to an aircraft manufacturer’s role, an analogy Boeing was happy to make in the same announcement, declaring the CST-100 to be “rocket-agnostic.” For its part, SpaceX continues to market the Dragon spacecraft to commercial users in the free-flying DragonLab configuration with two flights scheduled on its current manifest. Taken together, these developments, along with others, offer the tantalizing possibility of being the opening act in a new era of both public and private spaceflight to low Earth orbit.

Whether or not such a new era materializes, and to what extent, will be determined by many factors, but it seems clear that the scope and resilience of the market will be determined by launch costs. SpaceX is currently the runaway price leader with a price of no more than $56 million per flight for a commercial Falcon 9. While this figure represents definitive—even amazing—progress in reducing costs, it may also represent a floor. The price of space launch is still exorbitantly expensive, and incorporating the costs of achieving commercial crew promises to make it even more so. It remains to be seen whether higher flight rates can offset the upward pressure sufficiently to even maintain the current baseline. Consequently, without much deeper price reductions, which can only come from some form of reusability, an expanded commercial market in low Earth orbit remains very much in question. Seemingly, only SpaceX founder Elon Musk embraces the challenge, observing that if his company does not achieve reusability, “we will consider ourselves to have failed.”

From the moment the Obama Administration announced its decision to cancel the controversial Ares booster family and the Constellation program for which it was intended, a vacuum formed concerning what would fulfill the perceived need for a heavy lift space launch system. In the bitter and morbidly entertaining melee which ensued, the three primary players—NASA, the Obama Administration, and the Congress—as well as their supporters, appear to have forgotten the concept of reusability altogether. Instead, arguments have raged about the relative benefits of a particular shuttle-derived heavy-lift rocket configuration, either in-line or sidemount; Ares V boosters; or multiple launches of expendable rockets. Yet each of these proposals, and any new program of exploration beyond low Earth orbit for which they would be used, ignore the reality behind the painful but simple truth highlighted in the conclusion of the Augustine Committee that “no plan compatible with the FY 2010 budget profile permits human exploration to continue in any meaningful way.” As it now appears, with even the best-case scenario a five-year freeze at FY 2012 levels, as Jimmy Buffett would say, there’s trouble right here in River City.

The Department of Defense, proud owner of the EELV program, has its own problems. Aviation Week reported on January 14th that Secretary of Defense Robert Gates stated the need to increase the DoD budget for 2012 launch acquisitions by $450 million over previous estimates in part to “provide stability for the industrial base.” Launches under the ULA contract would increase from three to five per year starting in 2012 essentially to keep the ULA Atlas and Delta production lines in business. This is a privilege for which the taxpayer is already paying a costly annual subsidy in addition to the per launch price. Increasing the number of DoD launches should lower the average price for all users, but how much is another question. Rising prices from suppliers are fingered as the primary culprit in escalating ULA costs, and this is no doubt an important factor, but then again, that is part of the problem with an expendable system to begin with. Ford is experiencing rising supplier prices (and profits) as well, but that doesn’t materially affect the cost of a taxi ride because each fare doesn’t require a new Crown Vic.

Second Generation: the path not taken

While both the Atlas and Delta launchers have compiled an outstanding success record, the rising costs are a serious problem even for NASA’s unmanned space missions, which “only” pay the per launch cost. Presented with the $187-million price tag for a bare bones Atlas V Mars launch for 2013, one official quoted in the article pondered the implications and asked “How do we get out of low Earth orbit on a regular basis? ” Good question.

Ironically, in the first years of the new millennium, NASA was on the way to answering that question until a dizzying series of priority changes led to the current dead end. In the days before GPS, when you got lost on a diverging path, the only certain alternative was to retrace your steps to the point of departure and start over. Such is now the case with US space launch policy.

Ten years after Second Generation was originally conceived, one cannot help but observe that if policy makers had stayed the course, 2011 might have found the US close to fielding a TSTO reusable system rather than occupying essentially the same position as in 2002—or 1961 for that matter.

April 2011 will mark the thirtieth anniversary of Space Shuttle Columbia’s lift off in the first flight of the National Space Transportation System and our first attempt at lowering the costs of getting to orbit by reusing part of a launch system. As we all know, it came up a little short on that measure. The shuttle system was limited from the outset by a budget environment right out of today’s headlines. In 1971, the Nixon administration OMB imposed a five-year freeze on NASA’s budget, resulting in a design that offered lower development costs but higher operating costs. Nevertheless, it was a failure brought about by both attempting to achieve too much in one great leap, and betting everything on the outcome of that attempt. That it failed to lower costs says far more about the flawed specific approach taken than about the ultimate viability of reusable launch hardware in general.

Acknowledging that failure, as well as disappointing outcomes in subsequent X-33 and X-34 experimental reusable programs, NASA in 2001 established the Second Generation Reusable Launch Vehicle Program as part of the Space Launch Initiative. This time, the challenge of lowering launch costs through reusable flight hardware would be met by undertaking several developmental programs, including the X-37 Approach and Landing Test Vehicle, as well as the RS-84 reusable engine. The end result would presumably be a fully reusable two-stage-to-orbit (TSTO) architecture. While TSTO lacked the cutting edge allure of the single-stage-to-orbit (SSTO) approach, it also left behind the truly serious engineering challenges which bedeviled X-33 and left the proposed VentureStar flying in viewgraph form only. Instead, the TSTO path offered steady, linear, almost boring progress from existing technology base, with the absence of an appropriate engine being the biggest challenge. Second Generation started with a review of over 100 possible configurations, and called for following a down select process from 15 to 3 to 2 vehicle concepts, resulting in a development decision by 2006 and a potential operational vehicle in the 2010s.

Second Generation was one component of NASA’s 1999 Integrated Space Transportation Plan, which was envisioned as “living document” to ensure that NASA’s goals matched its actual requirements. Unfortunately, NASA quickly concluded that, according to this framework, the “must have” program of the moment was a new crew transfer and return vehicle for the International Space Station, so for FY 2003, the Second Generation RLV program was diverted to the Orbital Space Plane program. For its part, OSP would initially be launched by a human-rated EELV while retaining a possible transition path to a reusable launcher. Following the Columbia disaster, the Orbital Space Plane project gave way to the Crew Exploration Vehicle, as result of the Vision for Space Exploration announced on January 14, 2004. Project Constellation soon followed. Ten years after Second Generation was originally conceived, one cannot help but observe that if policy makers had stayed the course, 2011 might have found the US close to fielding a TSTO reusable system rather than occupying essentially the same position as in 2002—or 1961 for that matter.

Second Generation was, of course, only one of many projects over time that started with great promise only to be subsequently abandoned or altered beyond recognition. Like much else in life, it is quite easy to consider the path not taken through a gentler light than the harsh reality that comes with actual experience, and this may be the case with Second Generation. Any program can be mismanaged, any opportunity wasted, and one need look no further than current programs for confirmation. Virtually every development program appears to go over budget and take longer than originally scheduled. Nevertheless, disappointment is more easily avoided by pursuing the right goal in the first place.

Now, in the twilight of the shuttle program and with Constellation cancelled as unaffordable, the challenge the Space Launch Initiative and Second Generation RLV originally sought to resolve still remains. Financial reality suggests it is a challenge that still must be overcome if the US expects to witness a new era of private spaceflight, affordably launch defense payloads, or initiate a return to the Moon or venture to points further beyond. For anyone without a financial or political stake in the status quo, the original goal of the 2001 Second Generation RLV Program—“development of flexible, commercially produced reusable launch vehicles”—remains both logical and achievable, and absolutely necessary.