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Every week, it seems, we hear that NASA should be directed to halt development of the Ares 1 crew launch vehicle, pay industry to develop a human- rated EELV to fly the Orion crew vehicle, and focus its own efforts on the Ares 5 and Altair. Now, while a smaller Orion capsule on a human-rated EELV could cost less in the short-term to develop, it would only be capable of supporting the International Space Station. The lunar mission is more difficult; we're trying to go beyond Apollo, not merely repeat it. Our goal is to develop the option for sustained human lunar presence at the minimal level of an international crew of four rotating on six-month centers. Existing EELVs, even leaving aside the issue of human rating, cannot lift a lunar-capable Orion, without substantially compromising what is meant by "lunar capable". If "using EELV" doesn't really mean "using an existing EELV", but instead means, "using an upgraded EELV sufficient to carry a lunar-capable Orion", then I must note that this will require much more than the few tweaks that some have suggested. We would have to modify the first stage to carry heavier loads and for human rating, among other things, and then design, develop, and build a new human-rated second stage. But that's exactly what we're doing with Ares 1: modifying an existing first stage and building a new second stage. Why is it thought that this is a good thing to do with EELV, but not for Ares? Further, it is crucial to recall that we are designing an architecture, a family of space vehicles with synergistic commonality. We are not trying to optimize a single mission. Our analysis shows that for the complete architecture, the development costs savings for the Ares family are huge, about 25% lower than for an EELV-derived family, because of the commonality of Ares 1 systems with those on Ares 5. In fact, given that we must develop Ares 5 for the lunar mission and, later, Mars, the additional development cost for Ares 1 is $2.7 billion. I will repeat that: if you commit to lunar exploration and beyond with Ares 5, for an additional $2.7 billion you also get the new human-rated LEO transportation system mandated by the Columbia Accident Investigation Board. Aside from the upper stage tank structure, most everything on Ares 1 - many elements of the 5-segment solid rocket booster, the J-2X upper stage engine, the upper stage main propulsion system, the guidance, navigation, and flight control systems - is common to Ares 5. Constellation is not a point design. A spaceflight system designed for a single task - say Earth to LEO, or Earth to Moon - can clearly be optimized for that one task. In a world where NASA had substantially more money, it would certainly be desirable to build and optimize different systems for different missions. We are not in that world. I believe that, if we are lucky, we are going to get one new human space vehicle to follow Shuttle. Anyone here think that Congress is going to provide funding for more than one? Raise your hand, please. Anyone? ... I didn't think so. And if that's the case, then it would be a mistake to optimize that one vehicle for access to LEO. If we want to be a spacefaring nation, we have to be able to go to more than one place and do more than one thing, and we're going to have to sacrifice optimal performance on any single mission for versatility across an array of missions. That is why we must think "architecture" and not "point design". Beyond the costs involved, our probabilistic risk assessment for loss of crew on Ares 1 showed it to be twice as safe - I repeat, twice as safe - as a human-rated EELV-derived vehicle. This figure of merit was a significant factor in our decision to go with the Shuttle-derived Ares 1, yet is ignored by almost everyone suggesting that we make a change. I cannot responsibly ignore it, for reasons having nothing to do with money. But if to someone else it is just about the money, then the cost of unreliability must be considered. Incurring even one additional accident through the use of a less-reliable system wipes out all of the savings of the hypothetically cheaper vehicle. Solely from a fiscal perspective, we should be willing to pay a premium for safety, if necessary. So, while I am truly concerned about the moribund state of our U.S. commercial launch industry and about the rising costs of EELVs to NASA as a result, our task was to develop a plan for human space exploration, not to buttress the EELV industrial base. We absolutely do not have the resources to do both, and even if we did, exactly what is it that makes the EELV industrial base more important to support than the Shuttle industrial base? I remind everyone that with the Ares family, we are retiring the Shuttle orbiter, but preserving many other segments of the Shuttle industrial base. Why is it, exactly, that in this time of transition in NASA spaceflight systems, we should make decisions to augment the existing Atlas and Delta workforce, while completely decimating the Shuttle workforce? Now, as I say, I am concerned that rising costs for expendable launch vehicles will impact our ability to carry out our robotic science missions. In accordance with the Commercial Space Launch Act and national policy, the EELV will continue to be the foundation for launching NASA's robotic missions, and we will use them to the maximum extent possible according to our mission needs, performance, cost, and schedule requirements. We are also considering emerging commercial offerings, like SpaceX's Falcon 9 and Orbital's Taurus 2. When reliably flown, they will compete on a level playing field for NASA contracts. We are supporting the commercial launch industry where we can reasonably do so.
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