Space Transportation Association Roundtable "An Engineering Assessment of the Way-Forward in Human Spaceflight” September 9, 2010 Rayburn Building Thank you, Rich, for the opportunity to get together on this important topic with this group. Please let me begin with a disclaimer. While I am the Executive Director of the American Institute of Aeronautics and Astronautics, by no means do I speak for the Institute. We have some 36,000 student and professional members – including all four of us on the panel. Our volunteer leadership establishes our policy positions, and to be candid, it is an extremely difficult process to get consensus on almost any subject. With a topic as filled with options and differing views as what we are talking about this morning, we consider our role to be to provide opportunities to debate issues and bring out technically sound perspectives rather than advocate positions. So, I’m afraid I will have to use the standard disclaimer that the views expressed are my own. 1 Over the past few years Mike and I have discussed various aspects of the space exploration portfolio. On some we have agreed, on some we have agreed to disagree. Mike will be on the AIAA election Ballot in a few months to run for the same position he had to resign when he was confirmed as Administrator of NASA – President‐Elect of AIAA. I think it is both a characteristic and strength of AIAA that the senior staff person and the person who was a month away from being my boss, and may be again, can engage in debate on issues and agree to disagree. If the way ahead for exploration were simple, if the answers were straightforward, we wouldn’t find ourselves with a President’s Budget and bills or drafts from three of the four relevant committees that in some areas agree and in many others, often fundamental, differ. I’m not a rocket scientist, and except for a brief time when the Air Force was planning on doing Shuttle operations prior to the Challenger accident and later while I was at Cape Canaveral and had responsibility for Range Safety for all Eastern Range launches, including the Shuttle, I haven’t been involved in human spaceflight. On the other hand, I’ve spent enough time around expendable launch system development and operations to have collected a fair amount of scar tissue. Launching cargo or satellites is certainly a different proposition than launching humans. We treat the launches and vehicles differently and apply different standards to ensure the survival of the crew in the event of a mishap, including additional real‐time health monitoring of the 2 launch vehicle, the presence of abort systems and even Range Safety procedures. But from the perspective of the launch vehicle, it doesn’t much matter what’s on top. The mission is straightforward: deliver the payload to the right orbit at the intended time, safely. If that happens, the mission is a success. If it doesn’t, it isn’t. This country has been launching payloads to low earth orbit for more than fifty years. We’ve used an amazing and surprisingly large array of launch vehicles: various versions of Jupiters, Vanguards, Scouts, Thors and Deltas, Atlases, Saturns, Titans, Shuttle, Taurus, Athena, Minotaur, Atlas V, Delta IV, most recently now Falcon 1 and 9, and probably something that I’ve forgotten. That’s fourteen separate families of vehicles, and all but Saturn and Shuttle were mostly conceived, designed and developed by American industry. We’ve used modified ICBMs, Atlas and Titan, to carry humans to low earth orbit, and the mission‐specific Saturn to carry humans to LEO and the moon. We’ve used expendable rockets, and the largely reusable Shuttle. There’s nothing magic about doing it. It IS rocket science, and it takes enormous care and attention to the business to do it well, reliably and safely. But we know how to do it. And by “we” I mean this country’s aerospace community. Safe transport to LEO, for cargo and for people, hasn’t been the sole purview of vehicles built by the US government. To suggest that only a government, only NASA, can build a reliable, safe space transportation system, in my view, ignores history. 3 Similarly, I think it would be short‐sighted to think that as we look into the future, be it a few years or a decade or more, only government‐ sponsored astronauts will be travelling to orbit. I would be the first to acknowledge that the flights of SpaceshipOne to an arbitrarily defined altitude were a far cry from what I would call spaceflight. But I have no doubt that private citizens will travel to orbit on vehicles other than government rockets – be it for tourism or something else. And, while I don’t expect to do so myself, I’d be disappointed if my 20‐ year old son didn’t have the opportunity to make such a trip. Personal spaceflight will happen in the somewhat near future, and will be affordable to a private citizen that hasn’t won the lottery. And when it happens, it will be on commercial launch systems. To be sure, there’s a risk associated with relying on commercial providers for something like transportation to space – or for anything else, for that matter. Companies are in business to return on investment, and that can lead to decisions about risk‐reward tradeoffs that are different than for a system operated by the government with mission success as the overriding priority. We may wish that weren’t so, but history tells us otherwise. Anyone who lived through the rash of launch failures of the 1990s knows that to be so. While I certainly agree that very close and tailored government involvement is essential for any vehicle that will be carrying government payloads to orbit – people or cargo – and picking and 4 qualifying the right rocket and company is not a trivial process, I am probably much less concerned than some about the prospect of using commercial providers for routine access to low earth orbit. We’ve seen them do it well, for decades. The business case for use of commercial providers is another story. A couple of flights a year to ISS for crew rotation, and maybe a few cargo resupply missions, aren’t enough to provide adequate business for more than one or maybe two providers, and launch rate DOES matter when it comes to reliability and profitability. Personally, I prefer two, just as I prefer the government have two vehicles that can carry critical national security or other government payloads to orbit. In that regard, I think the government and the industry would be well served if the government were to act more collectively in decisions about future launch systems, and in how toda’s launches are procured. But that’s a different subject, perhaps for another day. So, in my simplistic, non‐engineering view, transportation to LEO should become as routine as we can make it, using systems specifically intended and designed for that function. We know how to do it. We’ve done it for five decades. We need to keep moving in that direction. Spaceflight beyond LEO, and very heavy lift to LEO in support of exploration beyond LEO, is an entirely different matter. We know how to lift more than a hundred metric tons to orbit – we do it every time 5 that big stack delivers Atlantis or Discovery or Endeavour to orbit. And while it takes a lot of people, a lot of work and a lot of careful attention to do it safely, the processes are about as repeatable and safe as anything we do in spaceflight. The problem, of course, is that only something like 50,000 pounds of all that orbiter weight is useful payload – in the same class as several expendable vehicles today. Where I guess I differ with many in the discussion of what I will call exploration lift, for want of a better term, is in timing and specificity. We – humankind – haven’t gone beyond LEO since 1972. We know how to get to the moon, and if that’s the vision, we know how to build systems to take us there and back. But if we want to go much beyond that, we don’t. The Lagrangian points are within our reach with the systems we understand, but many asteroids and Mars are not. In my view, 180 day transit times simply aren’t realistic for human travel. AIAA recently did a student space transportation design competition. The mission was to send at least two astronauts to an asteroid, land, collect an Apollo‐like quantity of materials and return to earth. Without exception, the design teams concluded that the mission couldn’t be accomplished without some fundamentally new form of in‐ space propulsion. A few months ago I failed a quiz from Joe Rothenberg. He asked what the transit time to Mars would be if you could accelerate continuously at 1 g. Obviously, you accelerate half the way then turn around and 6 decelerate. There are other maneuvers involved, but with that kind of propulsion, rough order of magnitude, what’s the transit time? Instead of the six months it took the Spirit and Opportunity, with 1 g acceleration it’s less than three days. Three days. At a perhaps more realistic tenth of a g, it’s still under 30 days. Missions that with conventional chemical propulsion don’t make sense become realistic. The problem, of course, is that we don’t have a clue how to build that new form of propulsion system.