Resilience

So, I was talking about (among other things) NASA’s lack of resiliency in its transportation plans yesterday, and I come across this short article on the value of resilience in sustainability:

Sustainability is a seemingly laudable goal — it tells us we need to live within our means, whether economic, ecological, or political — but it’s insufficient for uncertain times. How can we live within our means when those very means can change, swiftly and unexpectedly, beneath us? We need a new paradigm. As we look ahead, we need to strive for an environment, and a civilization, able to handle unexpected changes without threatening to collapse. Such a world would be more than simply sustainable; it would be regenerative and diverse, relying on the capacity not only to absorb shocks like the popped housing bubble or rising sea levels, but to evolve with them. In a word, it would be resilient.

Sustainability is inherently static. It presumes there’s a point at which we can maintain ourselves and the world, and once we find the right combination of behavior and technology that allows us some measure of stability, we have to stay there. A sustainable world can avoid imminent disaster, but it will remain on the precipice until the next shock.

Lynne Kiesling has some related thoughts on loosely coupled systems:

Loose coupling means that entities that are engaged in exchange have to understand and exchange certain kinds of information to make those exchanges happen, but these requirements are explicit, and they are not exhaustive. When I buy milk at the grocery store, I don’t have to know the name of the cow whose milk I’m buying … but I do want to know some product features, such as its fat content, the sterility of its production environment (here, admittedly, aided by safety regulations), as well as its price. If my transaction relies on that specific cow, that’s a more tightly-coupled relationship, and if she dies and the transaction relies on it being her milk, then the transaction fails. A simple-minded example, but you get the idea.

Loose coupling is like having shock absorbers at the interfaces between different entities and different systems in a complex “system of systems”. Loose coupling can help prevent the negative consequences of unexpected actions from propagating through the network, and that’s how it contributes to resilience.

[Both links via La Dynamista]

As for how this applies to NASA, I’m pretty sure that I’ve written about the subject before (google, google…)…yup, here it is:

I’ve written before about the high costs of space due to lack of economies of scale, but our minimal activity level causes other problems as well. It makes it difficult to afford a robust and resilient space transportation infrastructure.

In 1979, when a DC-10 literally lost an engine and crashed in Chicago, the whole McDonnell-Douglas DC-10 fleet was grounded. But this didn’t shut down the airline industry because there were hundreds of aircraft of many other makes and models which weren’t affected.

In contrast, we learned with the Challenger breakup the danger of relying on a single launch system. With a small number of vehicles, grounding means putting all activity on hiatus. A loss of an Orbiter would constitute the loss of a quarter of our fleet. The loss of another one after that would be another third of the remainder. And grounding the fleet to avoid this may result in more delays to the beleaguered space station program.

NASA has studies underway to look at solutions to this problem, such as the Space Launch Initiative, or the Alternate Access to Space program. But these programs seem to be stuck in the same mode of thinking that gave us Shuttle. People talk about “the” Shuttle replacement, or “the” next-generation launch system, as though there will be only one, because no one can imagine a market or funding for more. And all the focus remains on technology and vehicle concepts, which are beside the point.

No one in the government seems to recognize our real problem, which is the currently infinitesimal market size for space transportation. NASA continues to pay the traditional aerospace contractors for traditional solutions, and ignores the fact that we need a diversity of approaches and providers. Such a diversity can only be supported by a large, vibrant and growing commercial demand for space transportation services.

There is an old tale, about “for lack of a nail…a kingdom was lost.”

As long as we, as a nation, refuse to acknowledge the problem with our space markets and approaches, we will remain in our current state of fragility, in which the fate of a multi-billion-dollar space station which, for all of its cost, can only support three people is held hostage to the whims of microscopic slivers of metal in frigid propellant ducts.

This problem persists, in which NASA is developing two new launch systems, neither of which can replace the other. Beyond that, there are plans for only one lunar lander design, one earth departure stage design, etc. The failure of any one of these components means that we will be unable to go to the moon, so if we had a base there, it would be subject to being abandoned in the event of a Challenger-like event.

If we are serious about becoming spacefaring, and actually having and supporting bases in extraterrestrial locations, we have to have multiple means of getting to them (which is why being capable of using both EELVs would be a good idea). If NASA comes to its senses and builds depots, they will have to be redundant as well. If not, we will continue to have a very brittle (and unsustainable) infrastructure.

4 thoughts on “Resilience”

  1. I dont want to spam ( posted the link in previous post comments ) but in light of revisiting ESAS, its worth keeping mind what we had before:
    http://www.spaceref.com/news/viewpr.html?pid=15303

    Practically all of the proposals here advocate loose coupling. This was all before Mike came and did that:
    http://www.nasawatch.com/archives/2005/10/eliminating_ste.html

    “I have not seen the relevance to NASA and I have preferred a much more direct approach, and that is what we will be recommending and implementing.”

  2. The USAF will have plenty of F-35s (apparently they’re going to buy 2500 of them). That’s the plane to watch out for.

  3. Sometimes, even having several different booster types isn’t enough. From September of 1985 through about May of 1986, the US suffered a string of launch failures that grounded one booster type after another.

    1. Titan 34 (with a billion dollar payload) lost out of Vandenberg
    2. Challenger space shuttle
    3. Delta II carrying (IIRC) a GOES satellite
    4. Atlas carrying a FleetSat comm bird
    5. Another Titan 34

    For a while, the only US booster type that was still operational was the Scout, a light booster. At the time, I joked that we needed to develop a launch escape system for unmanned payloads.

    It’s much worse when we put everything on a single booster type, as NASA tried to do with the Shuttle and wants to do in the future with Ares.

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