The Space Review

Shuttle-derived launch vehicles illustration illustration
Developing a new generation of shuttle-derived launch vehicles may force NASA to accelerate the retirement of the shuttle itself. (credit: ATK)

Where do we go from here? Making the Vision for Space Exploration a reality

Ask someone you meet about the space shuttles; they’ll probably know that they were grounded but that Discovery has just returned the fleet to flight. Ask him or her about the Mars rovers, and they’ll probably know that they landed safely, and maybe even that they’re still operating. Then ask them about the Vision for Space Exploration.

The what?

The Vision for Space Exploration (VSE)—NASA’s new focus on a manned return to the Moon, to be followed by flights to Mars—has received incredibly poor publicity. That which it has received has generally been negative, featuring imaginary or otherwise bloated price tags to scare the public. (See “Whispers in the echo chamber”, The Space Review, March 22, 2004) While the plan is well known and generally well supported in the aerospace community, new NASA Administrator Michael Griffin faces an incredibly difficult task as he attempts to turn pretty viewgraphs into real hardware.

The biggest hurdle in the eventual implementation of the VSE is the danger that the 2009 or 2013 Presidential administration could issue a directive, formally or informally, essentially saying, “stay in LEO”.

The VSE has received some initial funding, and has recently received a positive evaluation from Congress in the form of the overwhelming passage of NASA’s new authorization bill, which supports the VSE. Lockheed Martin and Boeing/Northrop Grumman have done some initial design work for a key aspect of the VSE, the Crew Exploration Vehicle (CEV), and NASA is working to sketch out a timeframe for the execution of the plan. However, there are still huge hurdles for the plan that lie ahead. The most important question facing NASA today is how to ensure that the VSE doesn’t just produce another generation of paper spaceships. What can we do to ensure that we won’t go back to carving endless loops in the LEO racetrack? In other words, how can we make the implementation of the VSE irreversible?

The problem

The technology for a manned lunar mission is certainly close at hand today; the current plan would put humans on the Moon again in 2018, thirteen years from now. Thirteen years before the first lunar landing was July 20, 1956. There was no NASA. There was a not a single man-minute in space from any country; no payload had ever been put in orbit. No rovers were traversing other planets, and the integrated circuit was three years from successful completion. Thirteen years from that date, humans walked on the Moon. Clearly the issue in returning humans to the Moon is not technical. The problem is getting and sustaining the will to undertake the journey.

Because the funding for the VSE has already been clearly defined as coming from the existing shuttle and station budgets after their respective phaseouts in 2010 and 2016, the key challenge for NASA is not so much to find lots of new funding as to simply sustain the Presidential and Congressional mandate needed to undertake it. The biggest hurdle in the eventual implementation of the VSE is the danger that the 2009 or 2013 Presidential administration could issue a directive, formally or informally, essentially saying, “stay in LEO”. On the other hand, Congress could also deny further exploration funding. However, currently there is an administration friendly to the plan, with a Congress willing to give it bipartisan support, and, perhaps most importantly, highly skilled NASA leadership at the very highest level in the form of Administrator Griffin. It is unlikely that the VSE will ever enjoy a better time than now in terms of political support and funding prospects. The time between now and the end of the Bush administration in 2009 is also the period that will see the definition of the plan and the design of the CEV to carry it out. Therefore, the question must be asked: What is the best way to ensure irreversibility of the VSE, now, while major action can be taken without political opposition? Before answering this question, it is worthwhile to examine the changes made to the VSE implementation plan under the tenure of Mike Griffin.

“How did we get here from there?”

What has happened since the announcement of the plan in January 2004? What steps have been taken, and what’s ahead in the near future?

The initial CEV “procurement strategies” under Sean O’ Keefe would have seen two “phases” of CEV design. Proposals submitted this May were to be part of the Phase 1 portion of CEV design, which was to be followed by an orbital or suborbital fly-off of technology demonstrator spacecraft called FAST in 2008. Downselect to one contractor for Phase 2 of the program would have occurred later that year. First manned flight of the CEV would not occur until as late as 2014.

Mike Griffin has done away with this schedule, viewing it as unacceptably slow, and will move directly to Phase 2 in early 2006. He has commissioned a 60-day internal study within NASA, called the Exploration Systems Architecture Study (ESAS). Originally slated for release after the return of Discovery from STS-114, its release has now been pushed back to September 19 after reportedly receiving poor marks from reviewers and some resistance from the Office of Management and Budget (OMB).

The details about the ESAS that have leaked out by the eve of its official announcement suggest that Griffin plans to accelerate or otherwise change a number of aspects of the original plan released last year. Instead of a CEV fly-off in 2008, NASA will move to Phase 2 of the CEV program in 2006, with CEV flights to commence as early as June 2011. NASA will also develop two shuttle-derived launch vehicles: one derived from shuttle’s solid rocket boosters (SRBs) to launch the CEV, and an in-line heavy-lift vehicle using SRBs and the shuttle’s external tank.

The details about the ESAS that have leaked out by the eve of its official announcement suggest that Griffin plans to accelerate or otherwise change a number of aspects of the original plan released last year.

The heavy-lift vehicle would carry a large lunar lander, called the LSAM (Lunar Surface Access Module), which is attached to a fuelled Earth Departure Stage (EDS). The CEV would dock with the LSAM/EDS stack and fly to the Moon. The entire crew of four would transfer to the LSAM and descend to the lunar surface, leaving the CEV unoccupied in lunar orbit. The crew would stay on the Moon for a week and then return to the CEV in the ascent stage of the LSAM. The CEV would fire its own engines to return the crew to Earth; they would parachute back to Earth somewhere in the western United States. Differences from Apollo are the larger crew size, the much larger lunar lander (which would also carry large quantities of cargo), the use of two launches to support each mission instead of one, the fact that the crew would leave the CEV unoccupied in lunar orbit, and a land landing instead of an ocean splashdown.

The ESAS is also thought to contain a recommendation for retiring the shuttle after completing only six to eight additional flights to the station; this would require the remaining modules of the ISS to be launched on another vehicle, if they were to be launched at all.

So several changes have been made in the implementation of the VSE since its announcement. The shuttle will probably not be able to make enough flights to complete the station on its own, as was the original VSE goal in 2004. The CEV will probably fly with crews earlier than the stated deadline of 2014. It will be an Apollo-like capsule (rather than a lifting body) and will fly on shuttle-derived boosters. Other parts of the plan have remained unchanged: for example, one of the requirements of the plan was to fly lunar robotic missions no later than 2008. Such a mission, called the Lunar Reconnaissance Orbiter, is already being designed for launch in October 2008 and its payload has been selected. The retirement date of 2010 for the shuttle remains firm; if NASA wished to fly the shuttle after 2010 it may have had to undergo an expensive and time-consuming recertification, as recommended by the Columbia Accident Investigation Board. To date, the VSE has received mostly full funding, and it is likely that it will be continue to be funded at the requested level at least until the end of the Bush administration. The VSE is moving forward with growing momentum, and actual spacecraft have been designed for which construction will begin soon.

page 2: how we get there from here >>


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