Saturday, May 26, 2012

Can Constellation Rise from the Ashes?

Back in 2010 the Obama administration canceled Constellation, Bush's space program that would have sent US astronauts back to the moon, and eventually to Mars and beyond. I do not agree with President Bush on very much, but his ambition and vision for NASA was laudable, and I was sad when they cancelled Constellation. Despite being “over budget, behind schedule, and lacking in innovation due to a failure to invest in critical new technologies” according to the White House's budget plan, Constellation did provide an exciting and inspiring goal: Mars. The same cannot be said of Obama's replacement plan to focus on "building block technologies" and eventually send US astronauts to an asteroid. The goal is not nearly as romantic, and half the US population thinks it has already been accomplished. Moreover, with the recent explosion of Planetary Resources onto the public stage, we now see that there are market forces sufficient to propel private sector missions to asteroids; the same cannot be said of missions to Mars. In this new age of privatized space, NASA's main goal should be to fund innovative research and missions that would not otherwise be funded due to a lack of immediate profitabilityBut I digress. 

The Liberty launch vehicle combines the proven systems from NASA's space shuttle fleet and 
Europe's Ariane 5 expendable rocket. This graphic shows how they combine into the new 
ATK-Astrium Liberty rocket. CREDIT: ATK
It now seems that Constellation might just make like a Phoenix and rise from the congressional ashes. Development of the Orion Crew Module, which would have carried astronauts to Mars, has continued under the new title of "Multi-Purpose Crew Vehicle" (MPCV) since program cancellation. And now it looks like the heavy-lift vehicle, (née Ares 1), which would have propelled Orion into space, is not completely dead either. On May 9th, Alliant Techystems (better known as ATK) announced plans to combine the first stage of the Ares 1, a five-stage solid rocket booster, with the second stage of the European Space Agency's Ariane V rocket, which has been in use since '96, to make the "Liberty Rocket". These rocket stages would be topped with ATK's own Orion spinoff, with a composite structure and less robust heat shield than the metal Orion system since ATK's version would only be reentering the atmosphere from LEO instead of deep space and thus have half the energy to dissipate upon reentry. ATK plans to develop the Liberty Rocket system into a full-fledged commercial enterprise, carrying crew and cargo into low earth orbit for both NASA and other commercial space venture companies. ATK thinks it can move quickly through development and testing since the first two rocket stages have already been tested thoroughly. They hope to launch their first test flight by 2015.

I'm glad to see that the billions of dollars and thousands of hours of hard work already poured into Orion and Ares may not have been for naught, but I have reservations about the frankenstein nature of Liberty. Rand Simberg, in a great summary of the program, pointed out that using the Ariane V as a second stage (rather than as a first stage, as it has been used by the ESA) will mean coordinating in-flight ignition of the very complex combustion engine. The difficulty of pulling this off is one of the reasons that the Space Shuttle's SSME was abandoned by NASA's Constellation team for the J2-X. 

I also can't imagine that integrating 3 different rocket stages, built by three different companies, will yield an elegant, cost-effective, or scalable result. The Ariane 5 brings 15 years of ESA heritage technology with it, the Ares rocket undoubtedly possesses the marks of 60+ years of NASA history, and the Orion capsule is being developed by Lockheed Martin, which has its own hefty share of heritage. The plan greatly undervalues the benefits of in-house design. SpaceX, for example, built their entire system (rocket and capsule) from scratch in-house. The mechanical engineers building the Falcon engines eat lunch with the electrical engineers designing the Dragon capsule and the systems engineers building the operational plans (I saw this with my own eyes when I visited SpaceX headquarters in 2010). While an ATK systems engineer will have three sets of clumsy and likely incomplete documentation to sift through, and none of the original designers to help with the task, a SpaceX engineer who wants to know why something was built a certain way merely has to find the person who designed it and ask. ATK's kludged-together rocket might be cheap and fast now, but I doubt that it will be scalable or easily updated in the long-term. 

In any case, it is likely that Liberty - which will require support from the Ares team - will receive support from members of Congress who championed Constellation and would like to see those jobs return to their districts. It will be interesting to see how Liberty changes course once it enters the political sphere.

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