Category Archives: Space

From The Horse’s Mouth

Jeff Foust reports on Burt Rutan’s presentation at the annual symposium of the Society of Experimental Test Pilots last week in LA. Worth a read if you want to get the latest scoop on SpaceShipOne. He saves the most intriguing bit for last:

The final slide of the presentation, put on the screen during a brief question-and-answer session, showed what appeared to be a scaled-up version of the SS1 (see photo). A cutaway showed the cabin, with one pilot and ten passengers (arranged in three rows of three people with the tenth person floating above them.) The illustration was simply captioned ?A Future Space Tourism Ride??

Living Down To Expectations

When we last left Rocketman, he was accusing Gregg Maryniak of comparing launch vehicles to submersibles, an accusation that, knowing Gregg, I found quite unlikely.

He has since had an email discussion with Gregg, and clarified the issue. I found this little bit of Gregg’s response interesting, because it wasn’t something to which I’d previously (or at least recently) given much explicit thought.

Bottom line is that space stuff costs perhaps 500 times as much to develop historically as (very challenging) undersea stuff. Why? It may be largely because of the expectation that it should (based on the history of governments racing each other without regard to normal engineering cost contraints.) When I speak to big audiences of traditional government space program engineers and program managers I usually pray that one of them will ask me: “You mean to say that mere expectations can be cost drivers–ridiculous”…to which I say, I have two words for them….”stock market.”

Is Gregg right? Is space hardware and operations expensive because we expect it to be?

There’s actually quite a bit of evidence that it is.

Most space contracts, particularly government contracts are cost plus fixed fee. This means that the contractors are reimbursed for the actual costs of executing the contract, as reported by them, plus some amount for profit (typically a few percent of the contract value). This is because high-technology research and development is recognized to be high risk–that the schedule might slip, or the costs be greater than originally estimated, and few if any private companies
are willing to absorb those costs, and NASA knows that none would bid on any other basis.

The problem with this, of course, is that it skews incentives in a way that are bad for the taxpayer (though not necessarily for the true constituencies of the space program–the contractors themselves, and the congresspeople in whose districts the contractors employ people). Perversely, the more they spend, the more they earn. There are occasionally attempts to mitigate this by putting in bonuses for hitting cost targets, and penalties for missing schedules or overrunning the budget, but they’re largely ineffective, at least judging by the space station program.

But there’s a more pernicious result of this, that’s less often considered. In order for NASA to project the cost of the contract, they have to have a way of estimating the costs, even if it’s something that may have never been done before. The way they (and the contractors) typically do this is called parametric cost analysis. They have cost models that are built up by examining many past programs, and incorporating the cost and schedule data from those programs. The models might use factors such as complexity (which is hard to measure), weight, technology level, and so on. The hope is that a good cost estimator can come up with a valid estimate for the program cost and schedule, based on similar efforts that have been performed in the past.

One problem with this is that it’s more art than science, and heavily dependent on the assumptions that the modeler uses. Another problem, of course, is that reinforces notions of how expensive things will be, because by definition, it’s based on how expensive things were in the past. It doesn’t provide any way to model true innovation. In addition, because almost all of the experience comes from government programs, the data base for private space activities is very sparse, so they don’t have any way of modeling that with any degree of credibility. And it turns even government programs, given the right team and incentives, can beat the estimates. As an example, consider the DC-X program:

Prior to letting the DC-X contract our program office conducted a cost estimating study. We used three models, one developed internally, one used by the US Air Force and one from NASA. The results were that our cost estimate based on the rapid program assumptions I described earlier and projected a cost between $60 and $70 million, the Air Force model using standard aerospace procurement practices produced an estimate of $365 million, the NASA model based on highly technology development based shuttle program experience projected the program would cost over $600 million. The actual DC-X program cost through the first test series came in around $65 million.

In other words, they beat the conventional Air Force costing model by a factor of more than five, and its NASA equivalent by almost an order of magnitude, or factor of ten.

Sadly, here’s the process (slightly oversimplified). NASA comes up with a program idea. They come up with a cost estimate for it. They request a budget. If Congress authorizes it, they put out a procurement for that budget target. The contractors write their proposals, and then come up with their own cost estimates that magically, and almost invariably turn out to be close to what NASA has money for. And thus the expensive game is perpetuated.

But as one more example of how such estimates and quotes can be voodoo, let me relate a story (possibly apocryphal, but it’s certainly believable to anyone with experience in the business) that was told to me by a program manager from the seventies. In the process of submitting a proposal, a small, almost insignificant typo found its way into the final version as delivered to the customer. It was a decimal point, misplaced one place to the right, resulting in a bid for that part of the program ten times too high, relative to the contractor’s internal estimate.

The contractor was downselected for a Best And Final Offer, which is an opportunity to negotiate a little bit. The contractor fully expected to be raked over the coals for their outrageously high bid (I think that it was something like ten million dollars, when it should have been one), and they weren’t disappointed. The NASA contracting officer excoriated them, calling them crooks and cheats, and other names not mentionable in a family web site, and finally finished up his lecture with the words, “…and we’re not going to give you a dime over nine million!”

And of course, the outraged response from the contractors’ representatives (as they sighed with relief) was, “But we can’t do it for that!”

Farewell To A Space Probe

Galileo (the spacecraft, not the scientist) is going to plunge into Jupiter’s atmosphere tomorrow, ending its many-year exploration of that planet and its many moons. NASA is deliberately dropping it into the Jovian atmosphere in order to prevent it from accidentally hitting one of the moons, such as Europa, which may harbor life, and thereby contaminate that body with earth life that may have somehow survived the many years in deep space and Jupiter’s intense radiation fields.

This weblog has a warm feeling for the spacecraft, which had a very hard life. The picture of the earth and moon in the banner was taken by it on one of its gravity-sling encounters, in which it stole a little momentum from the earth-moon system to augment its trip to the gas giant. In its honor, I’m displaying it in this post in more detail.

I don’t like to anthropomorphize spacecraft, but it was a doughty explorer, and despite the rocky start to the mission, delivered a wealth of new information about our system’s largest planet and its satellites. May it rest in peace.

[Thanks to my web designer Bill Simon for the heads up]

Cheap Satellites Follow Up

Rocketman has a post on the X-Prize and related subjects that’s worth reading, but there are a couple problems with it.

This is the most egregious:

The difference in energy required for a vehicle to reach the 100 mile altitude necessary to achieve orbit is ~25 times greater than the energy necessary to reach an altitude of 50 miles (I leave it as an exercise for the readers to figure out the difference in energy necessary between 62.5 and 100 miles).

This makes no sense at all. The difference in altitude between 50 and a hundred miles is, well, fifty miles. It’s merely doubled, so it makes no sense that it would be twenty five times the energy.

The problem of course, is that there are two components to energy–the specific potential energy as represented by the altitude (approximated as gravity times the altitude), and the kinetic energy, corresponding to the velocity (half the velocity squared). By ignoring the latter, this statement comes out completely garbled (and the exercise left for the readers is utterly meaningless, and would be frustrating to any who attempted it). Energy is a combination of both altitude and velocity, and the big problem in getting into orbit isn’t the former, but the latter.

Orbit is harder because it has go faster, not because it has to go higher. X-Prize is probably achievable at Mach three or four (say, a couple thousand miles an hour), and getting to a hundred miles wouldn’t require much more energy. Orbit requires seventeen thousand miles an hour–that’s the real killer.

He makes another point that’s more arguable (as opposed to physical nonsense), and I’ll argue it, as I did in last night’s post and today’s Fox column.

The statement that the “‘harsh environment’ of space was less harsh than that imposed by the ocean on the submersible” is just silly. Deep Rover operates in the ocean at a maximum depth of 1000 meters (3280 ft). At that depth, you are surrounded by water that is at ~40 degrees F and ~120 PSI. In space you are in a vacuum and your vehicle is exposed to direct solar energy that heats up one side of the vehicle and the vacuum of space that cools off the other.

The temperature extremes that exist in space create some difficult engineering problems because of the differences in thermal contraction and expansion that occurs between dissimilar materials. I have had to deal with these problems in my designs, and it is not trivial to engineer effective solutions.

Unlike vehicles that operate in salt water, the choice of materials that can be used in space is extremely limited. Most common materials get brittle at cold temperatures, and they also outgas in a vacuum, which changes their material properties. Some materials have problems with salt water, but there are many common materials that can be used under the conditions Deep Rover operates at.

But the biggest difference between a submersible and a spacecraft is that submersibles do not have to fly. You can afford to have relatively large factors of safety and, if necessary, redundant components in a submersible because weight is not a big issue. Also, spacecraft are subjected to tremendous dynamic and acoustic vibrations during launch, vibrations submersible never see. Designing and testing components to handle the vibrations of launch is again not a trivial problem (I speak from experience on this as well).

No matter what Maryniak would like to believe, space is an extremely harsh environment to design for. It also is not cheap to test components to determine how they will handle that environment. You cannot just sail out to deep water and drop your vehicle in the ocean to test it like you can with a submersible. Environmental chambers with liquid nitrogen ?cold walls,? large halogen lamps and huge vacuum pumps are needed to conduct these tests. And even the largest of these chambers is incapable of testing a complete launch vehicle, so components have to be tested individually.

They’re both harsh environments–but they’re different kinds of harsh. The marine environment is extremely corrosive, and it’s much more difficult, from a structural standpoint, to deal with many atmospheres of positive pressure (the deep sea) than a single atmosphere of negative pressure (the vacuum of space). Yes, space has radiation and temperature extremes that the ocean doesn’t, but both environments are harsh. For example, the choice of materials that can operate in salt water are limited as well.

Many of the implications of expensive launch are subtle, but they validate Gregg’s (and my) point.

Every objection that he has would be obviated by cheap launch, a point with which even he agrees at the end. If launch were cheap, you could afford heavier satellites, because the additional mass wouldn’t be so expensive. If launch were cheap, you could afford more redundancy. Cheap launch systems will have relatively smooth rides (because they’ll have to in order to be reliable and affordably reusable) so the launch environment won’t be an issue. Cheap launch implies affordable test facilities on orbit, so the components can be tested more easily.

So I’m not sure what his point is in arguing with Gregg on this issue.

Non Sequitur

Gregg Easterbrook gives a little history of the Biosphere venture, and how Columbia University has finally ended its affiliation with it. But in the process, he makes a glib comment about the affordability of a Mars mission:

It seems certain that as the space shuttle debate continues, some prominent person will advocate the bold new adventure of a trip to Mars. When someone advocates that, this blog will demolish the idea in detail. Here’s a quick preview. Last week the Wall Street Journal ran a letter to the editor blithely asserting that colonization of Mars could be accomplished “easily and cheaply.” The Russian rocket manufacturer Energia recently estimated that the hardware for a stripped-down manned mission to Mars would weigh a minimum of 600 tons in low-earth orbit. At current space shuttle prices, it costs $15 billion to place 600 tons in low-earth orbit. That’s just the initial launch cost for a stripped-down high-risk flight with a couple of people–spaceship and supplies are extra.

Sorry, Gregg, this does not compute. Why would you take the word of Energia for the mass of a Mars mission, and then make the insane assumption that it would be delivered with a Shuttle (probably the most expensive launch system on the planet, and one to soon go out of business, one way or another)?

If you’re going to go with Russian quotes, use Russian launch prices. Of course, any rational person, contemplating fifteen billion dollars in launch costs, might consider spending that money instead on reducing launch costs…

Dang

Don’t you just hate it when your multi-million-dollar satellite falls over and breaks?

Way to go, Lockmart…

Keith Cowing over at NASA Watch provides the following reader comment:

“It turns out that the POES group at GSFC had a training session for an ISO 9000 audit in July, 2003. Here’s the link to the briefing slides.

The accident appears to be LockMart’s fault, but once again we see the benefits of an ISO 9000 program…”

NASA’s Vietnam?

An email from Andrew Case informed me of an item that Clark Lindsey over at RLV News found. Homer Hickam (author of Rocket Boys, the book on which the movie October Sky was based) has an op-ed in today’s Journal (subscription required, unfortunately), titled, NASA’s Vietnam.

…when I put emotion aside, I can’t ignore my engineering training. That training and my knowledge as a 20-year veteran of the space agency (and also a Vietnam vet) has led me to conclude that the Space Shuttle is NASA’s Vietnam. A generation of engineers and managers have exhausted themselves trying to make it work and they just can’t. Why not? Because the Shuttle’s engineering design, just as Vietnam’s political design, is inherently flawed.

He thinks that NASA doesn’t have a culture problem, just a lousy vehicle design. He wants to build an OSP and fly it on an expendable. That will make everything all better!

Sorry, Mr. Hickam, with all due respect to your cherished agency, it has both. It has a lousy design partly because of a cultural problem, partly because of a policy problem, but there’s much more to be fixed at the agency, that simply coming up with a different expensive and unsafe way to put people into space isn’t going to solve.

I know that it pains a veteran like you, but we need to fundamentally break the connection in the minds of both the public, and policy makers, between NASA and space. They are not synonymous. It’s time to open up the competition and let some other folks give it a shot.

Besides, I’ve always thought that Space Station Albatross was NASA’s Vietnam, and that we should just declare victory and go home.

[Update at 4 PM PDT]

For those who want to Read The Whole Thing, there’s a slightly longer version of it up at Spaceref now, with a different title–“Not Culture, But Perhaps A Cult.”

[Update on Saturday afternoon]

It occurs to me that this piece, which I wrote last fall, is relevant to this topic.

NASA’s Vietnam?

An email from Andrew Case informed me of an item that Clark Lindsey over at RLV News found. Homer Hickam (author of Rocket Boys, the book on which the movie October Sky was based) has an op-ed in today’s Journal (subscription required, unfortunately), titled, NASA’s Vietnam.

…when I put emotion aside, I can’t ignore my engineering training. That training and my knowledge as a 20-year veteran of the space agency (and also a Vietnam vet) has led me to conclude that the Space Shuttle is NASA’s Vietnam. A generation of engineers and managers have exhausted themselves trying to make it work and they just can’t. Why not? Because the Shuttle’s engineering design, just as Vietnam’s political design, is inherently flawed.

He thinks that NASA doesn’t have a culture problem, just a lousy vehicle design. He wants to build an OSP and fly it on an expendable. That will make everything all better!

Sorry, Mr. Hickam, with all due respect to your cherished agency, it has both. It has a lousy design partly because of a cultural problem, partly because of a policy problem, but there’s much more to be fixed at the agency, that simply coming up with a different expensive and unsafe way to put people into space isn’t going to solve.

I know that it pains a veteran like you, but we need to fundamentally break the connection in the minds of both the public, and policy makers, between NASA and space. They are not synonymous. It’s time to open up the competition and let some other folks give it a shot.

Besides, I’ve always thought that Space Station Albatross was NASA’s Vietnam, and that we should just declare victory and go home.

[Update at 4 PM PDT]

For those who want to Read The Whole Thing, there’s a slightly longer version of it up at Spaceref now, with a different title–“Not Culture, But Perhaps A Cult.”

[Update on Saturday afternoon]

It occurs to me that this piece, which I wrote last fall, is relevant to this topic.