An American fableby Stewart Money
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| Achieving reusability is, as Musk succinctly observes, “super damn hard.” |
In Aesop’s fable of the Ant and the Grasshopper, the grasshopper is presented as a frivolous creature who happily plays throughout the summer, consuming its resources, only to starve with the onset of winter because unlike the ant, he did not prepare for the lean times ahead. With SLS program office already cautioning that funding requirements might “push to the right” an initial crewed flight as far as 2021, it seems possible that a Congress who specified the rocket’s makeup may be leading the space agency to a similar fate. For those hoping to avoid a bad ending, there may be some comfort to be found in 1970’s TV icon Kung Fu, who redeemed the notion of the grasshopper somewhat, employing it as a term of affection for one who has “much to learn.” It was perhaps in this sense that we were introduced to SpaceX’s Grasshopper Reusable Launch Vehicle, and soon thereafter found out just what it is seeking to learn.
SpaceX observers already knew something was afoot with the publication of an FAA draft environmental assessment dated September 22, revealing the company’s plan to begin flying a reusable test vehicle, dubbed Grasshopper RLV, at its recently expanded McGregor, Texas, test facility. As described in the application, the Grasshopper will be used to test reusable vertical takeoff and landing flight regimes, and will consist of a Falcon 9 first stage powered by a single Merlin 1D engine, and equipped with a landing structure comprised of four steel legs. The proposed range of testing is relatively modest, lasting three years and beginning with a series of flights to 75 meters (240 feet). It culminates with flights to a maximum altitude of 3,500 meters (11,500 feet). By contrast, a recently failed Blue Origin test vehicle was lost at 13,700 meters (45,000 feet) while traveling at Mach 1.2. The key difference, however, is that as a video released in concert with Musk’s speech makes clear, the purpose of the Grasshopper program is to develop a tail-first, rocket-powered vertical landing technique for both stages of an already flight proven vehicle, the Falcon 9.
It will not be easy. Achieving reusability is, as Musk succinctly observes, “super damn hard.” So far, recovering an intact booster in any condition has proven problematic. As SpaceX has learned, the Falcon 9 flight profile causes it to hit the atmosphere in a “belly flop” position severely damaging the first stage. As anyone who is old enough to remember the existence of diving boards, much less high dives, before an overly litigious society protected us from ourselves, belly flops hurt, and probably should be avoided where possible. Taken from the video, the proposed solution to this problem is to restart three of its engines after stage separation in order to slow the first stage and ease the transition into the atmosphere. The booster would then descend to a tail-first powered landing similar to that demonstrated by the DC-X and being currently pursued by Blue Origin and Armadillo Aerospace, among others. What is not clear from the video, though, is how SpaceX proposes to fly the vehicle back to the launch site as opposed to landing at another destination, such as a platform at sea, a line of approach apparently being pursued by Blue Origin.
If SpaceX can perfect the first stage recovery technique, the next step is returning the second stage safely from orbit, a more demanding task given the much greater reentry speeds and resulting heat that will need to be managed. To address this, the SpaceX video shows reentry achieved by firing an extendable engine and the addition of a blunt heat shield at the top of the second stage, followed by a powered landing via several small dedicated thrusters on the perimeter of the base. While still challenging, SpaceX stands to benefit from considerable commonality between its first and second stages, as well as experience already gained from developing the reusable heat shield that allowed it to successfully recover the Dragon capsule on the company’s first attempt.
The final moments of the video depict a Dragon capsule separating from ISS, and returning to Earth via a powered touchdown courtesy of its side-mounted pusher launch escape system, without the aid of parachutes at all. While an eyebrow lifting proposition, it would be even more surprising if SpaceX had not done the math to ensure it is achievable. In any event, according to Musk, the redundant parachutes will remain as a safety backup to the landing thrusters, which are themselves redundant; a four-layer arrangement that offers a safe return for even a completely disabled capsule. The only item expended is the Dragon service stage, although for standard commercial launches, neither the Dragon nor its service module would be used anyway. Given the overall company approach, one wonders if SpaceX is not contemplating some future use for even that hardware in orbit as well.
As an aside, while the video is interesting enough, for anyone who takes a moment to look up the lyrics to the accompanying soundtrack, the Muse song “Uprising”, you cannot help but crack a smile. These people are having fun. Muse, by the way, bills themselves as wanting to be the first band to play in space, so it’s not too hard to figure the royalties they are expecting from SpaceX.
| If SpaceX does in fact succeed, then the key to that success most likely lies in the very unique corporate culture and the deliberate manner in which they have aligned their business approach to their corporate goals. |
For SpaceX supporters and detractors, a definitive program in pursuit of reusability provides a bonanza of new ideas to pick over and debate. Musk himself readily admits the difficulty of what his company is undertaking, and the very real possibility of failure, but he says, “we are going to try.” Given his launch vehicle is named after Star Wars’ Millennium Falcon, even if Elon Musk has not fully embraced Master Yoda’s admonition to “do or do not, there is no try,” his competitors have yet to even match Bart Simpson’s slacker response to promise to “try to try.”
If SpaceX does in fact succeed, then the key to that success most likely lies in the very unique corporate culture and the deliberate manner in which they have aligned their business approach to their corporate goals. SpaceX is following a business plan that will allow it to pursue reusability through the normal course of its operations in the form of a parallel development effort. So long as the company is able to book commercial launches, it will be able to sequentially test the components required to reach its goal without interfering with market activity, and with its customers, in fact, paying for much of the effort.
This fortunate situation is a direct result of two factors. First, SpaceX’s initial decision to enter the market with a simple vehicle powered by a reusable engine of its own design, which was robust enough to at least allow the possibility of an upgrade to reusability. This conservative approach allowed SpaceX to debut as the lowest cost player in the market with a launch vehicle likely to succeed on both a financial and technical basis. The second factor is the absolute refusal to innovate on the part of its rivals. While it may take a number of years to even get an expended first stage in a position to fly back to the launch site, it is that lack of cost-effective competition in the domestic market that is likely to grant SpaceX those years.
As if more evidence were required, Space News reported on September 30 that NASA had informed the European Space Agency that it could not afford an Atlas V launch in support of the joint ExoMars mission to that planet in 2016. While ESA is having funding difficulties as well, it should be noted that prior to the notice, the mission had already been scaled down to allow NASA to budget a less expensive version of the Atlas in the first place. In the curious world of government-subsidized launch contracting, the very same inefficiencies and lack of competitive ambition that drove Boeing and Lockheed Martin to form United Launch Alliance are buying precious time to allow SpaceX to compete with itself in the effort to lower costs.
For those who would contend that tradeoffs are simply too great, and that SpaceX will inevitably join the list of other companies who tried and failed to achieve reusability, it interesting to consider first one implication of the uncontrolled cost increases on the part of its domestic rivals. At the price SpaceX is quoting for the Falcon 9 Heavy, $80–125 million, the company could in all likelihood beef up the first stage to withstand re-entry and water recovery—build “just the right suit of armor,” in Musk’s words—and despite the weight penalty still produce an upper-end medium-class launch vehicle with a reusable first stage significantly less expensive than any of its domestic competition. Whether it would be less expensive than a standard Falcon 9 is perhaps a more relevant question.
If partial reusability were its only objective, SpaceX might be satisfied to pursue just such a plan. But for SpaceX, reusability, and what Musk characterizes as “rapid reusability,” are not just a goal, but also a means to a greater end. It is for this reason that the SpaceX announcement may prove to be of far greater and more lasting significance than the immediate reaction would suggest.
| The image of Dragon capsule perched on the surface of a Mars, juxtaposed with the same basic craft carrying American astronauts into space, would suggest that it is time to iron flat most of the turns in “flexible path” and get on with the business we left in 1972. |
Elon Musk has been saying the since founding SpaceX in 2002 that the purpose of his company was to make possible the settlement of Mars. It was a statement perhaps easily dismissed as the company struggled through growing pains to launch its Falcon 1 rocket, enduring three failures before finally achieving success on September 28, 2008. Clearly, the difficulties encountered in launching that modest vehicle seemed completely incongruous with such grander goals. Even as SpaceX secured contracts, attended conferences, and produced viewgraphs showing larger and larger rockets, ultimately including the Saturn V sized “BFR” it really wants to build, the slow pace of actual rocket launches pushed future developments into far future developments and provided ample fodder for critics.
The future may be a lot closer than it used to be. The official announcement of the Falcon Heavy, also made at the National Press Club earlier this year, marked the introduction of comparatively affordable launch vehicle with the capacity to lift 53 tons to low Earth orbit, sufficient to support a return to the Moon in two flights and even launching meaningful payloads to Mars. The fact that it is based on the flight proven Falcon 9 vehicle strongly suggests that it will succeed on a technical basis.
With a single successful launch of the Falcon Heavy, Mars is officially within reach of a company whose overriding goal is to reach Mars. And it may get there sooner than anybody thought, as it was revealed this summer that SpaceX is in discussion with NASA Ames for a 2018 “Red Dragon” Discovery-class mission in which the company would utilize a Falcon Heavy to launch to Mars a Dragon capsule equipped with a drill for digging below the Martian surface to look for signs of life. The image of Dragon capsule perched on the surface of a Mars, juxtaposed with the same basic craft carrying American astronauts into space, would suggest that it is time to iron flat most of the turns in “flexible path” and get on with the business we left in 1972. Based on the rancorous debate leading up to the introduction of the SLS, one can only imagine the carefully veiled but vehement Congressional and internal opposition such a mission might engender in the effort to avoid unflattering comparisons.
The initial success of the Falcon 9 and the introduction of the Falcon Heavy are revolutionary enough. If over the coming years, however, SpaceX is able to successfully transition the Falcon to a fully reusable launch vehicle, then the stage on which the entire arena of space exploration is cast would be radically redrawn. Simply put, with the advent of a fully reusable Falcon series of rockets, a heretofore unforeseen level of space exploration becomes not simply more affordable, but in all likelihood, unavoidable. Once a permanent human presence on Mars is within practical reach, failure to pursue it, many will argue, becomes a moral transgression against humanity itself. To be sure, Musk’s vision of thousands of émigrés to a new world will have to wait on new, even larger rockets, but his company has a plan for that as well, beginning with a large staged combustion engine it wants to begin building next year.
While “within reach” does not mean “within grasp”, it certainly bears serious consideration from a space establishment about to consume the better part of a decade and plow, at an absolute minimum, the equivalent cost of 144 Falcon Heavy flights at 53 tons each into a single 70-ton launch by 2017. With a projected launch rate of no more than once per year, and the 130-ton super-heavy version of the SLS expected no earlier than 2032 and sporting a price tag almost certain to exceed $40 billion, it is not a stretch to believe that SpaceX has a better chance of achieving reusability with the Falcon than the Senate has of achieving orbit with the heavy version of its “monster” rocket.
| For those who work for, or believe in, the value of a permanently expanding human future in space, the advent of a fully reusable launch system is, and always has been, the key to that leap, and success has been a long time coming. |
While there is risk associated with believing a sea change may indeed occur and acting accordingly, there is also a risk in assuming it will not and therefore not acting all. We are rapidly approaching the point where the risk of latter may outstrip the former. In any great endeavor, there comes a time when all who would count themselves as part of the moment must make a decision before the outcome is well certain, whether they are in or out. The early adopters—those fervent souls who believe in a successful outcome in the absence of evidence to confirm it—can be troubling and supremely annoying to those have been around, have seen it all fall apart before, and are sure they know better.
As the rhythm of the seasons brings us to the Major League Baseball playoffs, culminating in the World Series, network cameras will inevitably focus on handmade signs for one side or the other stating simply “We believe.” It happens every year. The cynic will point out that for every team that rewards the faith of its fans, there is another on the scoreboard that will disappoint, and even more that never made it at all. But when it is your team, and the victory that has been so long in coming is just starting to look possible, it is all in the leap.
For those who work for, or believe in, the value of a permanently expanding human future in space, the advent of a fully reusable launch system is, and always has been, the key to that leap, and success has been a long time coming. SpaceX is years, perhaps decades, away from that moment. However, at this moment, it is the only team on field. Hopefully, sooner than we think, others will join them. One thing is for certain: to his credit, Elon Musk has made clear his intention to pursue the goal, and more importantly, provided a credible path for reaching it. In doing so, the SpaceX founder has ensured that sooner or later, those who would be part of the moment must decide for themselves if they believe, or risk being left behind at the launch pad.