January 23, 2010
Beyond LEO – Flexible Path Revisited
Teleoperated robots can emplace and build much of the lunar outpost infrastructure prior to human arrival (Astrobotic Technology Inc.)
In an interesting post at Vision Restoration, “Ray” tackles the desultory Flexible Path (FP) architecture of the Augustine committee, which calls for human missions to low gravity destinations and delays missions to the lunar and martian surface. The problems he finds with FP are similar to points that I’ve discussed in a previous post.
The principal rationale for doing Flexible Path rather than the current program for return to the Moon is to avoid the cost of developing a new surface lander spacecraft for humans (either lunar or martian), which Augustine pronounced budget-busting for NASA. By being “flexible” and avoiding deep gravity wells, the Augustine committee saw a low cost way to send people beyond LEO. However, the Orion crew module and some type of heavy-lift booster still must be built.
Augustine committee member Jeff Greason discussed the FP architecture during a recent appearance on The Space Show. Jeff pointed out that many people missed the principal rationale for the advancement of FP as an alternative to the existing program – that while we cannot afford the current ESAS architecture because of the requirement to do several developmental projects simultaneously (or nearly so), we might be able to afford to do it sequentially, so that development of the Altair lunar lander would only begin after we had developed and flown the Orion and its new heavy-lift launch vehicle. In his conception of FP, Jeff sees increasing space faring capability over time as robots and people visit new and more distant destinations. The FP destinations described in the Augustine report are the Lagrangian-points, near Earth asteroids, and martian moons Phobos and Deimos.
Ray points out that the two alternatives discussed in the Augustine report (Moon First and FP) assume a roughly $3 billion per year increase in the NASA budget. He suggests that this is unlikely, especially on a continuing basis, a supposition made even more credible by recent stories in the space press. The alternative he offers to Augustine’s FP takes a slightly different tack to the cost problem. Ray’s solution, called Flexible Path to the Moon, shortens the destination horizon for FP and restricts it to cislunar space (GEO, the Earth-Moon L-points, and lunar orbit).
With Flexible Path to the Moon, we develop routine access to all cislunar space, which adds important national security and economic dimensions to the human spaceflight program. Ray would defer not only the Altair lander but also (and this is critical) the new, proposed heavy lift vehicle called for by the Augustine report. Instead, FP to the Moon uses existing and future commercial launch vehicles for LEO access and for the subsequent build up of transfer nodes, in-space re-fueling of vehicles, propellant depots and other features of the Augustine FP architecture. Ray’s plan further calls for “a large number” of robotic missions to the Moon and other possible destinations prior to human arrival.
I like this architecture and have advocated a very similar approach that builds up space-faring capability incrementally and cumulatively—take small, affordable steps and make time and schedule the free variables. We make progress as we can with a sustainable architecture and build an infrastructure that is cumulative, inevitable and inexorable. One thing should be added to Ray’s architecture: a statement of the “mission.” The purpose of lunar return is to learn how to use the resources of the Moon and space to create new capabilities and a sustainable human presence in space. This mission statement fits well with Ray’s mission architecture. The significant level of robotic missions that he advocates in Phase 1 can be focused specifically on resource prospecting, characterization and demonstration. We can begin to produce resources using robotic missions and machines teleoperated from Earth well before the arrival of the first humans, who will then have the assets of life-support consumables, propellant, and electrical energy to draw on when they arrive.
The Flexible Path to the Moon offers the build-up of new technologies and capabilities in space by using an incremental approach that falls within existing budgetary constraints. It forgoes the building of a new heavy lift launch vehicle by creating a reusable, extensible space transportation system infrastructure using existing launch vehicles. And it focuses efforts and builds infrastructure in cislunar space, where virtually all of our assets reside. These are the stepping stones we need into the Solar System.
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There has never been any significant development funds for the Altair vehicle. And funding for the Ares V and the Altair was always going to be funded sequentially– after the Ares I was developed.
As a strong opponent of the Ares I/V architecture, I would argue that its actually faster and cheaper to simultaneously fund an inline SD-HLV along with the Orion-CEV, an EDS (Earth Departure Stage) and the Altair vehicle. Why?
The Orion and Ares I programs are currently receiving $3.4 billion a year. Plus NASA’s $18.7 billion budget is an increase of $1.5 billion from last years budget. If the Ares I is terminated, then a total of $2.6 billion a year is now available. Only $1.2 to $1.6 billion annually are going to required to fund the development of the Orion and space vehicle operations and integration. So that leaves at least $1 billion in extra funds.
The termination of the $3 billion a year Space Shuttle program will raise the extra funds available to $4 billion a year. That $4 billion could be used for SD-HLV development, which shouldn’t cost more than $2 billion a year during the peak of its development. That leaves $2 billion a year for the development of an EDS and the Altair– vehicles only essential for lunar or beyond LEO missions. NASA has estimated that the total development cost for the EDS stage to be around $2.5 billion and the total cost of the Altair to be around $4.2 billion. That’s $6.7 billion in total. But NASA should have $10 billion in extra funds over the course of just 5 years. So that’s plenty of money to fund the EDS and Altair. And even if the EDS and Altair development cost doubled ($13.4 billion) and was delayed for a couple of years, NASA would still have a total of $14 billion in funds over that time period.
Of course, once the development phase ends, nearly $8 billion dollars of former development money will suddenly go into manned space flight operations for the Moon. And if the ISS program is terminated at that time then a total of $10 billion will go into lunar operations on an annual basis. And this is plenty of money for a Moon base program!
Comment by Marcel F. Williams — January 23, 2010 @ 2:57 pm
Marcel,
It may well be possible from a budgetary perspective to devise an Apollo-style architecture along the lines you suggest (although whether NASA is technically capable of doing it is questionable), but that isn’t my point. I am arguing that such is not what we need!
I am advocating the development of an extensible, permanent infrastructure in cislunar space for the purpose of routinely accessing all of cislunar space — GEO, L-points, Moon. The whole point of going to the Moon is to use its material and energy resources to help create a true space faring infrastructure. The good part of Flexible Path develops these pieces — departure stage, in-space fueling, propellant depots and staging nodes. The bad part of FP develops new (and unnecessary) heavy-lift launch vehicles for throw-away, one-off, touch-and-go missions to NEOs and Phobos
The very last thing in the world we need in our national space program are a series of dead-end, pointless PR stunt missions and space “firsts” that leave no legacy capabilities, infrastructure or technology. In other words, FP as currently being envisioned by NASA will just be the next Apollo redux, only writ small. The problem with our space program is not the target destination — it’s the way the agency does business. And if they don’t figure out a way to change their business model, they’ll soon be out of business.
Comment by Paul D. Spudis — January 23, 2010 @ 3:19 pm
Griffin and the Congress managed to turn a lunar base program into Apollo redux program.
But we do need a lunar base program since the primary purpose of the manned space program should be colonization, commercialization, and industrialization and not exploration. So I see a permanent Moon base as the first step in that direction. Plus a continuously growing Moon base provides a desirable destination for the emerging private manned space flight industry.
Permanent structures beyond the Earth’s magnetosphere are going to require a significant amount of mass shielding to protect against galactic radiation and major solar storm events. And there’s no way we’re going to be able to afford to launch such huge quantities of mass to a Lagrange point, plus the fuel needed to move such heavy craft through interplanetary space without developing either nuclear technology or lightsail technology.
An Asterant lightsail program could probably import thousands of tonnes of small asteroids to the Langrange points annually for fuel, air, water, and mass shielding.
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20040084672_2004088388.pdf
But I look at the Flexible path as a politician’s dream program. If you want to go to an asteroid, or to the Moons of Mars, all they have to say is, well we don’t have the mass shielding to do it right now with our chemical rockets– but we’re working on it and maybe someday we’ll have the funding for it! But, meanwhile, we can circle the Moon again like we did way back in 1968 for your entertainment! The Flexible path could well end up being missions to nowhere for decades to come while Russia,China, India, Japan and the EU may be colonizing the Moon!
Comment by Marcel F. Williams — January 23, 2010 @ 11:06 pm
But we do need a lunar base program since the primary purpose of the manned space program should be colonization, commercialization, and industrialization and not exploration.
You’re preaching to the choir. Tell that to the agency, not me.
Permanent structures beyond the Earth’s magnetosphere are going to require a significant amount of mass shielding to protect against galactic radiation and major solar storm events.
Not for facilities that are only sporadically and temporarily occupied. No one is advocating permanent human installations there. Propellant can be delivered to L-points via “slow boat” SEP cargo vehicles while people use “fast” chemical transport.
But I look at the Flexible path as a politician’s dream program.
As currently understood by Augustine and the agency, I agree. That’s why I like Ray’s idea — it takes the good features of FP (incremental, infrastructure creation) and discards the bad parts (throw-away assets, PR stunts).
It wasn’t just “Griffin and Congress” who turned the VSE into Apollo redux — it was the entire agency who never 1) understood or 2) embraced the VSE mission of lunar return. They dream of a human Mars mission and literally everything is subordinate to that goal. Want proof? Have a look at this:
http://www.nasaspaceflight.com/2010/01/taking-aim-phobos-nasa-flexible-path-precursor-mars/
Flexible Path to NASA is all about feeding their “Mars Forward” fantasies. The endless loop of “viewgraph engineering” studies, architecture development, and no flight missions has begun again. We are right back to where we were in 1992, after SEI died.
Comment by Paul D. Spudis — January 24, 2010 @ 5:12 am
I’ve always viewed the Flexible Path as a stealth Mars First program. The irony is that we’d probably already have permanent settlements on Mars if we had done what was logical right after the Apollo program– and established permanently manned bases on the Moon.
Plus the Augustine Flexible Path chemical rocket scenario doesn’t even get us to the moons of Mars until after 2030. By 2030, the use of chemical rockets for interplanetary travel might be rendered completely obsolete by future nuclear or light sail technologies that could possibly transport humans and payloads to Mars much faster and cheaper. If President Obama chooses this scenario, NASA’s manned space program could be set back for decades, IMO.
Comment by Marcel F. Williams — January 24, 2010 @ 3:04 pm
Interesting discussions. Genuinely wish that I could say otherwise. Unfortunatley, this sounds to me like yet another proposal to further emasuclate the US manned space program for the sake of private business interests.
The truth is that, although space is not cheap, it is cheap enough, compared to the federal budget, and to proposed increases in federal spending, that we can easily afford it, if we choose to do so.
It appears to me that politics must be removed as much as possible from NASA’s direction in order for such a long-term program to ever accomplsh anything. Get bipartisan congressinal approval, maintain the required budget, without any OMB interference, and let NASA accomplish it’s mission.
By 2020 there will be tested, proven commercial crew launch to LEO capabilities. Encourage NASA to include design elements into their architecture to make use of those services where advantageous. Until then, do not hold NASA hostage to the safety, reliability, functionality, and financial success of this fledgling industry.
One opinion. One voice.
Comment by Nelson Bridwell — January 24, 2010 @ 3:44 pm
If you want to remove politics, get a Moon base going. If one was going now, there is no way the present administration could touch it. Just listen to the clamor to preserve Shuttle and ISS. Strangely, it is these reusable, “boring” systems that only make the top fold of the front page when they blow up that have proved to be the most successful in terms of institutional staying power. It is the PR stunts that tend to get the axe. This Mission to Phobos stuff is just asking for it.
A lunar base might not make headlines everyday, but (a) like the South Pole Station and Little America, it would last as long as the USA is a going concern (i.e., it would never get technologically obsolete like Shuttle, and it would never have to be deorbited), and (b) isn’t a normalized, stable space program that’s ordinarily below the radar screen what we want?
But, apparently for some of these people, it’s like that first landing on the Moon was their first hit of crack cocaine, and so the purpose of NASA is to chase the memory of that high and strive to regain it, even if only briefly and imperfectly. But they’ll never quite get it back, and even if they come close, they will never be satisfied. The fact is that even a human landing on Mars will make less of a PR splash that Apollo 11. Why? Because of the we’ve-been-there-done-that factor. That second rock will never get you as high as that first rock–or so I’ve been told: that whole sort of mentality leaves me cold.
Anyway, Paul, I saw your terse comment at nasaspaceflight.com on the Flexible Mission to Phobos in addition to the mention above. Perhaps you could vent a little and expand on your thoughts on the matter. Your fans will appreciate it. Thanks again.
Comment by Warren Platts — January 24, 2010 @ 6:42 pm
Hi Warren,
apparently for some of these people, it’s like that first landing on the Moon was their first hit of crack cocaine, and so the purpose of NASA is to chase the memory of that high and strive to regain it, even if only briefly and imperfectly. But they’ll never quite get it back, and even if they come close, they will never be satisfied.
This is a very interesting analogy and I think that you are really on to something. I’ve argued in previous posts that “space firsts” and PR stunts are a poor basis for a sustainable space program. But NASA has been trying for 40 years to “recapture the Apollo excitement”, even though there’s no real evidence that such would lead them to the goal of their holy quest (more money). Your explanation is as good as any I’ve read on this. And I agree with you about the first Mars landing; not only the robot probes but 50 more years of science fiction (and ever improving CGI effects) has made the reality of space a disappointment. But this is not a bad thing. Now, we can get down to doing business there, like a real frontier.
Comment by Paul D. Spudis — January 25, 2010 @ 4:59 am
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I like the flexible path to the moon better than the flexible path mentioned in the Augustine Commission report. We have to get the most benefit out of the moon if we want to one day land on Mars. Does anyone know if the EELVs can launch a crew to the moon? I like the EELVs because of their proven safety record.
Comment by Rock Peterson — March 27, 2010 @ 5:36 pm
Rock,
There is a published report on a lunar return architecture that uses commercial launch vehicles. You can read it here:
http://www.ulalaunch.com/docs/publications/AffordableExplorationArchitecture2009.pdf
Comment by Paul D. Spudis — March 28, 2010 @ 4:58 am
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