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Plan B For Outer Space

By dennis_wingo
May 5, 2008
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Plan B For Outer Space
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In 1992 as a student enthusiastically working on projects associated with the Shuttle, tethers in space, small satellites, and the Space Exploration Initiative (SEI), I, along with some fellow students wrote papers about technologies that could be used in the return to the Moon effort. One conference that we wrote a paper for was the American Society of Civil Engineers Space 1992 conference in Denver Colorado, which at that time was a wellspring of great academic and research interactions regarding practical approaches to building Lunar and Mars outposts.

During this time I kept a daily diary of my interactions as this was literally at the dawn of today’s Internet and we still used paper for many things. At this conference were many NASA luminaries and at one panel discussion a startling, and in hindsight prophetic statement was made. The statement that is in my diary goes “SEI by 1994 or will not happen until after 2004”. The person that made this statement was the head of NASA Code X (X for exploration), and his name was Dr. Mike Griffin. Dr. Griffin also stated that without the SEI the United States would begin to fall behind in aerospace technology. It seems that with 14 years of hindsight that Dr. Griffin was exactly right on both counts.

Those of us who were disappointed with the demise of SEI shared the frustrations that I am sure that Dr. Griffin shared and is trying to fix today with the ESAS architecture. NASA is furiously working to make the Ares 1 overcome its problems while also looking to the future in the development of the Ares 5 and the retirement of the Shuttle. However, there are many of us out here who were around then, I have written before, think the same forces that killed SEI are going to kill the ESAS architecture and Constellation systems. The chances of this are high enough that like a prudent military commander, we need a plan B for space. This is not going to come from NASA just as there was no plan B in 1993. Therefore as a service to the community that is desperate for a plan B, the following plan is offered for consideration.

Critical Features of Plan B

The follow-on to the shuttle and the vehicle that returns humans to the Moon is not a business decision, but a political one. Therefore political considerations are paramount. At this time there are four primary political considerations that any plan B has to address and these are:

  • Reap the science harvest for the U.S. and International partners for the $100 billion spent on the International Space Station.
  • Workforce retention and continuity.
  • Open the Moon and beyond to exploration while leaving enabling low earth orbit as the domain of commercial space
  • Close the American human spaceflight gap as much as possible

These four considerations force a Solomon’s choice on NASA, Congress and the aerospace community. We cannot have it all so we have to make choices on how to carve up the space program into viable chunks that the nation can afford and can buy into in the moral choices between space and other priorities. As military strategists are wont to say, the perfect is the enemy of the good, so the question is, is there a “good” solution that satisfies the above requirements? In other words, is there a possible politically workable plan B?

The problem with positing a plan B today is that NASA has been pummeled for the past three years in relation to plan A and has put up their defensive shields and will not consider anything but the current plan. This is too bad as the agency and its engineers are working very hard to make the current system work, but it is highly unlikely that the current plan is going to be funded after the election, just like in 1993. Therefore we have to do it for them (I have received a lot of professional input on this but most of them work on the current contracts and are more than willing to allow me to fall on the sword and make Dr. Griffin mad on this in the hopes that something constructive will come out) and hope that if Dr. Griffin or his successor sees that plan A is dead that they will remember plan B and make it work.

Shuttle C + EELV + ISS + International Participation as Plan B

Shuttle C

There have been many variations of Shuttle Cargo (C) designs over the years so a clarification is necessary. The lowest cost, fastest schedule system for a Shuttle C is the version shown in the image here of the version that basically is a Shuttle with the wings and crew compartment removed. A Shuttle C with this capability could loft about 45 metric tons to ISS and as much as 52 metric tons to a 28.5 degree orbit.

Critics will correctly immediately point out that this is inadequate for boosting a human mission to the Moon. However, if the payload is sent to the International Space Station, these payloads can be aggregated into enough payload with two launches of a the Shuttle C and an EELV-lofted CEV to do a lunar mission. It may be that we will have to sacrifice the capability to send four crew to the Moon but that is three better than zero.

The value of the Shuttle C as configured here is that it requires no changes to the launch pads at KSC, no changes to the VAB high bays, and only minimal changes to the payload handling system at the pad to deal with the longer length (85 feet vs 60 feet) for the extended cargo bay. In the original Shuttle C studies of the late 80’s and early 90’s the cost for developing the system was minimal, less than a billion dollars according to an external report and no more than $2 billion by NASA. If you include a recoverable SSME pod this might go as high as four billion dollars but would eliminate the $35-$50 billion for the development of the Ares 1 and Ares 5. It would take a lot of Shuttle C flights and years of operations to equal that amount of money.

As an engineering solution the Shuttle C as described is far from optimum. It does not fully take advantage of the throw weight of the Shuttle system as it is volume limited and a larger volume would be nice. However, larger volume would require a lot more changes at the Cape, which negates the larger cargo volume, especially if you want this system to fly soon. Further, these losses are offset in that performance is at least partially used in getting the system up to ISS or to a higher orbit. As a political solution it does solve three of the four problems above. It is becoming increasingly clear that the Shuttle is going to fly beyond Sept 10, 2010 and Congress may force the issue as it pertains to the gap in human spaceflight and the ability to fly spare parts to the station. A Shuttle C with the same cargo carrying ability and connections as the orbiter could carry anything that has ever been designed by NASA for the orbiter. This brings in another facet of why this is a good solution: our international partners.

The Role of ISS in Lunar Development

For years now our European partners have been upset because it seems like the day that their investment of tens of billions of dollars in hardware is lofted into orbit, NASA wants to walk away from that investment. Congress has been less than thrilled about this as well. Today NASA says that this must happen as it is not efficient to go through the station to get to the Moon. While this may be technically correct, it is politically tone deaf and in the end self-defeating.

The station, even at 51.6 degrees inclination, is an amazing outpost in space. With the truss almost complete, the European module in place and the Japanese Kibo addition just weeks away, the station is becoming what we always dreamed it would be, our first outpost in the sky and while it is far from the perfect location, it is a good location to support return to the Moon. From there we can take advantage of the European, Japanese, and even Russian cargo and human carrying systems. This also extends to the commercial systems such as the SpaceX and Orbital Sciences COTS systems. Eventually if SpaceX gets their Dragon human carrying system operational, it is conceivable that non NASA explorers could depart from ISS to the Moon. How would this be accomplished?

During the SEI Era there was an amazing cadre of engineers who sought to maximize the utility of the Shuttle system to support exploration. One of the concepts shown here (designed by Brand Griffin and illustrated by Paul Hudson) was a lunar lander that would fit in the cargo bay of a Shuttle or Shuttle C. This lander carried its payload in a center section where it could be easily lowered to the surface, a much simpler arrangement than the top loaded payloads that are required when a conventional launch vehicle is used. The Shuttle C lander used four RL-10 engines in a horizontal arrangement that took advantage of the layout of the long and narrow cargo bay, which moots the argument by some that the cargo bay layout is insufficient for a lunar lander. With modern control systems and RL-10’s used at 50% power this system provides an abort to the surface fully redundant system. This horizontal arrangement would negate the need for heavy lifting devices to remove payloads from top loading lunar landers.

This system could be sent to the Moon by itself ahead of the human crew that would depart from the station via a concept developed during the late 90’s by NASA as part of their Orbital Aggregation and Space Infrastructure System (OASIS) study carried out under their Revolutionary Space Concepts studies office. This concept called a Crew Transfer Vehicle or CTV looked like this:

NASA OASIS Crew Transfer Vehicle (CTV) (Reusable)

This reusable vehicle, when married to an aerobrake, would allow for crews to be transferred from the station to lunar orbit and back again. In order to do this there needs to be a transfer stage. This transfer stage could be reusable or expendable, brought up on the Shuttle C as a payload and could use the same RL-10 engine packs as would be used on the Griffin horizontal lander.

There has been a lot of very competent work done on this concept and at least part of it was the NASA baseline at the beginning of the SEI era. The problem this was that that the space station had to be built before anything else could happen, along with a heavy lift launcher (Shuttle C). Well we have the station now and a Shuttle C solves a lot of the problems that confront the program now. That leaves the EELV to deal with. Also, going through the station gives a perfect entry for ESA, our long-suffering European partners, to participate. The Ariane V could be used to bring up cargo and payloads, including extra propulsion packs. A slightly modified ATV could be used to provide an initial boost of the CTV from the station to a higher orbit, to increase the total system performance. The Japanese and Russian ISS partners would also have a seat at the table and could contribute to the ultimate return to the Moon, one that works with our friends, rather than leaving them in the lurch with the billions that they invested in the station infrastructure.

EELV/Orion

The last part of this equation to deal with is the Orion. Part of the reason for the gap is that NASA is trying to develop a launch vehicle with inadequate performance at the same time they are trying to build a vehicle that can carry crews to the station as well as to the Moon and beyond. This is creating enormous problems for the NASA and contractor teams that so far have not been solved. The General Accounting office has roundly criticized such practices in the Defense Department in a newly published evaluation of the reasons for the lack of cost control of military space and other programs. If the GAO report findings hold for NASA (which is being done by the same contractors), we can expect huge overruns and there are indications that this is already happening in the Orion/Ares programs.

In the plan B outlined above, the Orion vehicle would no longer carry crews to the Moon, so a lot of mass savings could be had that would solve the weight problem. It would solve it so well that no longer would the CEV have to ride on the Ares 1 and that part of the system becomes no longer necessary. The latest iterations of the Ares 5 no longer use anything from the Ares 1 but the J2-x engine. Since with the Shuttle C the Ares 5 becomes a moot point, tens of billions of dollars can be saved by just moving a lighter weight, less demanding Orion that only goes to ISS over to the Atlas V or Delta IV heavy launch vehicle. The J2-x would survive and would still provide its role for an Earth Departure Stage.

This cannot be an impossible dream in that both Robert Bigelow and Elon Musk are designing similar vehicles. Also, by reducing the number of requirements that each system has to satisfy, lower development costs can be had and the savings applied to doing things on the Moon that we must do to open the space frontier. With this approach and by standardizing hardware, the same avionics that are used for the Orion could be used for the CTV, the lunar lander, and any other hardware that we send to the Moon.

Synthesis

This missive started out with the contention that with an election coming up and with none of the current candidates expressing enthusiasm for increasing NASA’s budgets by the amount that is necessary to support the current ESAS plan, we need a plan B. This plan B must solve the political problems of workforce retention, close the American human spaceflight gap, enable ISS utilization, bring in international participation, and preserve our ability to go to the Moon in a budget-constrained environment. In 1992 our current NASA administrator stated that if SEI did not happen by 94 that it would be delayed to 2004 and history has proven him right. He has worked mightily to create momentum that will keep going after this election but with the problems that daily crop up with both the Ares 1 and Ares 5, and with the unhappiness in Congress over making Brevard county Florida a ghost town as happened after Apollo, we must develop a plan B that Congress can buy into. In 1993 there was no plan B, and it was only with the incorporation of the Russians as a foreign policy goal that the space station itself survived by only one vote in congress.

The above is by no means the only idea out there and technically perhaps not the best, but the perfect is the enemy of the good, and with a good plan B, we can do the things we need to do while not requiring more money than our congressional investors are willing to spend on this effort. I don’t fault Dr. Griffin in his planning as I know that he is amazingly dedicated to this effort and shares our vision of a positive future, but without that plan B, it is unlikely that we will have any plan at all.