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Archive for the ‘ESA’ Category

Or The Space Game, by ESA.

The Space Game Screenshot

Minimize delta vee by moving the planets around (this changes the probe's arrival time at the planet). This shows my best solution so far, with some playing one evening, about 13 km/s

This is a nice javascript webpage where a probe is shot from Earth to Jupiter with gravity assists at Venus (twice), Earth and Mars. You try to achieve the lowest propulsive delta vee. You decide when the spacecraft arrives at each encounter and the program basically calculates the rest. It’s quite a nifty little piece of Javascript, the future of web applications is like this. It works fine with Chrome on Linux at least. Probably IE will have problems but who uses that anyway?

I’m ranked at #39 at 12.74 km/s… Far behind the gurus who get below 10 km/s readings! There are apparently some prizes for the top three, but I think people are in it for the fun of it.

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Rand Simberg talks about impedance matching. So I’d like to make a post of my comment there (I’ve always wondered why this obvious alternative gets mentioned so little…)

What to do when you arrive at Mars or Earth with your solar electric propelled vessel?

So, the problem with most low fuel demand velocity change schemes is that they only give slow accelerations. Low fuel high velocity change means solar or nuclear electric propulsion and aerocapture mainly.

High delta vee aerobraking is hard to do in one pass – it gets dangerous because of atmospheric variability and potentially other reasons.

Simple: detach a small capsule with the humans that goes directly to the surface (with only days of life support) and leave the untended craft to do multi-pass aerobraking. Hitting van Allen belts a few more times or taking a long time doesn’t matter that much with no humans onboard.

You could also potentially ultimately leave the long distance craft at some Lagrange point instead of LEO. (Cue some clever and complex maneuvers to save fuel – maneuvers that take long.)

Something similar could also be done when a long distance stack is assembled in LEO: send the humans there only after it’s through the belts. They can go with a smallish capsule again. Potentially at some Lagrange point, or in space without any fixed reference, just along the way. It could be dangerous though if the capsule doesn’t have much life support.

Many of these things have potential delta vee penalties as well as timing inflexibilities, but they could have enough other benefits that they should be considered.

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At the Science and Society picture library. Note the many small independently hinging peroxide/kerosene Gamma chambers, the large but cancelled Larch engine, the washing machine / musical box guidance computer with a rotary drum that has bumps, and many other things.

The British seem to be very engaged in nostalgia and “only if” in the aerospace sector. The country was bankrupted by two very heavy wars, and its empire was being dismantled at the end of the latter war. Some of its launcher technologies were quite good but somehow it could not transform into the more modern European capability that would then come through the French, mainly, after some abortive efforts by many parties and their joint ventures. Part of this was the promise by the Americans to launch European payloads on Deltas. Except when said payloads then started competing commercially with American ones…

I’ve seen and touched the Europa launcher at Oberschleissheim, Munich. It’s not as big as one would think. It also seemed complex and fragile with all the truss work, wires and pipes going everywhere. Corrugations and spot welds. Still very advanced compared to the V-2 chamber standing next to it, but otherwise it seemed somewhat anachronistic.

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The Man. On Space Review. [EDIT: About a month ago, but I only just read it.] This is just excellent. So many things I agree with, that go against the stupid myths of spaceflight and space policy. If you read one space policy interview this year, this should be it!

“NASA is an organization that is dominated by fixed costs. In business terms everything is in the overhead,” he said. The committee found, with some effort, that the fixed cost of NASA’s human spaceflight program is $6–7 billion a year. “The bottom line is that they can’t afford to keep the doors open with they money they’ve got, let alone do anything with it.”

However, he said, if you’re trying to minimize costs, it makes more sense to use a smaller launch vehicle that flies more frequently and has other users and applications. The key to making that work for exploration architectures that require large amounts of propellant—and hence have driven the planning for heavy-lift vehicles like the Ares 5—is the use of propellant depots and in-space propellant transfer. “If you use in-space propellant transfer, it’s no longer true that you have to have a really big piece,” he said.

He said that while he had his own opinions on the right selection of launch vehicles, he didn’t have any insights on what direction the White House and Congress would go. “It’s really up to policymakers whether we have a space program or a jobs program.”

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Jeff Greason is a rational person who simply gets it. It is mind boggling how completely opposite from someone like Mike Griffin he is.

See Jeff’s presentation with the Augustine Panel.

Paraphrasing, “we could go to Mars with Ares V but we shouldn’t – cause we couldn’t stay anyway”. Exactly. That’s the problem with NASA. (or the major one)

I bet he will be ignored completely.

Also, I would like to work for that guy. Too bad because of ITAR I couldn’t work in the USA.

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Nice video explanation of the SABRE engine by Richard Varvill.

In a sense, it boils down to the problem of changing the hot fast low pressure intake air flow to a cold slow high pressure flow.

In the Sabre engine, techniques somewhat similar to liquid air plants are used: there is a compressor, that is coupled to an expander, the expander runs from the “waste” heat of the compressor. This is efficient, but it is heavy. In Sabre the compressor is the shock cone (the jet engine style compressor only compresses the cooled air).

The heat exchangers are critical, and I wonder how reliable and expensive they will get with the vast temperature envelopes, ice and thin wall problems of the huge number of tubes there are. On the other hand, such heat exchangers could have uses in many other places as well. (Power generation.) The helium in the tubes is especially leak prone.

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Note, this text was originally posted as a comment on Rob Coppinger’s Hyperbola blog at flight international.

I hope there was more expansion in the “third way” for space journalism, at the moment it’s more like the big professional publications relaying NASA and ESA etc PAOs and company press releases, while blogs and forums are pushing snark and rumors (mostly false, but there are technical people there that help checking that at least some).

Not being entirely fair here, but it’s easier to describe it so briefly without nuances.


There are sources that are not official that can still be used, which if reasonably verified (signed documents, court evidence class are the ultimate of course, but there are lesser things) are much better than rumors. That’s the job of the journalist to investigate and not just propagate press releases. Watergate happened because of strong journalists driving for the truth to be uncovered. Aviation Week wasn’t used to be called Aviation Leak for nothing etc etc… I don’t mean you’re not doing investigations, just that there should be much more of it, and more resources being put into it too.

There are more things besides Ares or human-rated EELV:s.

What about the Galileo satnav farce? (And I don’t mean the traditional US vs EU stance taken.) How could EADS buy SSTL? There are probably tons of people inside the program, both on the industry and on the government side, just wanting to get their stuff known. Incompetence, corruption, shameless narrow self interest driving, etc. there is that like in every industry… Once again, a journalist gatekeeper with a good sense of the problem needs to make this all heard, otherwise it just goes into either silence or an anonymous rumor mill, loads of unverifiable claims and mud slinging. For democracy to work, the media is extremely important. Government and EU procuring is a very obscure process to the voters.

Mainstream space journalism is too kind. On the other hand, many forums and blogs are too snarky and amateurish.

There needs to be enough investigation to uncover the dirty secrets and there needs to be technical competence to understand what the issues are. That’s the third way for space journalism. Real investigation and criticism to the point.

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Sometimes

…stuff like this makes me think it’d be cool to be an astronaut. But the 20 year waiting of on and off flight opportunities, constant staying away from your family, random accidents killing people, and the complete helplesness of the individual at the hands of a vast governmental organization just don’t make me so interested as a whole.

I guess it’s pretty similar to the military in that sense.

Private spaceflight could change that. And I don’t mean paying 20 million to fly on Soyuz, but doing real spaceflight as useful work in private organizations. Still, the level of investment put on a single spaceflight will be so high that the person going will not have much freedom of choice on when to go, or what to do once up there. But it’s orders of magnitude less than with NASA or ESA.

That’s one of the reasons why Rick Searfoss has been having so much fun flying XCor’s X-Racer rocket powered airplane compared to the space shuttle (which must have been fun too but in a different way)… Sure, XCor’s got a lot invested in the plane, but there are so many flights that you are not in supertight control and can actually enjoy one. That is possible because the thing is safe and is not tossed away after each flight. 🙂

Link from Loretta Hidalgo Whitesides.

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Rand Simberg has discussion on some stuff that’s vital for an efficient spacefaring future. I feel those ideas of making fixed price contracts where the contractor bears all the risk are a bit oversimplified, but hold a lot of truth and usefulness. Motivation is a very important aspect of business and work, that I have witnessed myself very closely.

This is the kind of stuff that never makes any headlines or thinking in Europe. I’m very saddened by the fact. People feel so very sheepish about the politics and the military industrial complex and never talk about it. Be it the notorious Galileo satellite positioning system or any other big government-industry partnership that is ridden with problems and involves huge amounts of money. Small innovative companies get swallowed by huge ones and no-one even notices. Is that really good for European competitiveness? If we lack the skill of introspection and self criticism in business and government and EU contracting practices, can we expect to be efficient? Hell no. We must not be blind to our internal problems. Many fields have consolidated very far where a few big companies control their fields.

Journalism has a huge gap here. We need engineers and businessmen, people with a clue about the actual substance, writing on what really happens to those billions of euros of money that the taxpayers keep paying to their governments and to the EU. This is not some childish anti-EU rant. What we need is substantive criticism. Stuff that really increases knowledge and understanding and enables, even demands improvement.

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I’m quite that just right now. It will pass. Perhaps.

There’s been some discussion in various places about both NASA and potential future launch vehicles. Everything’s just so static in a large sense. Completely hopeless. I’ll throw in the towel for now.

Almost nobody has the required long attention span or patience to make any useful progress on the space front, and certainly not society itself.

The Players

USA is the only instance that is putting any significant money into doing anything new. And that’s wasted on the Ares rockets. ESA consists of a bunch of bickering countries, they’ve achieved some nice things but most of the people in the parttaking countries don’t even know they exist. No significant money spent on doing anything new, and what is done in Europe, is very often just me-too copying of American approaches. (Take Hermes as an example.) India is running with some crazy hypersonic stuff. China is doing intermittent Soyuz copy PR flights. Japan is doing something overcomplicated and abortive like they have always seemed to.

What are we left with? A bunch of US newspace companies with so little funding they won’t reach much in the next decade (Euro real newspace like SPL has zero funding at the moment). Scaled’s Spaceshiptwo is a dead end propulsion wise with the hybrids, and the air launching provides some scalability problems too. Maybe XCOR’s Lynx will fly some tourists to some altitude, and maybe there might be some X-racers. It won’t change stuff radically. The X-15 lessons were tossed to the trashbin too, to make way for the farces of NASP and X-33. Armadillo might fly something newish. So what? They don’t have enough money to even put turbopumps on the vehicle, resulting in ridiculous performance for orbital missions.

SpaceX? Forget it. It’s a rerun of Orbital Sciences Corporation, at best (and at the moment it looks much worse). No revolution, and evolution only very slightly.

COTS? Maybe something will actually fly, as it seems it has to try to pick up the mess that NASA put itself in with Ares and Orion. I’m not so well versed into the coming phases and how the politics will go. Both Lockmart and Boeing are in Ares/Orion so they don’t have such strong incentives to replace it with their own COTS solution flying on EELV on the short term. Depending how tightly they can keep their own ULA/EELV guys on a leash, and that has been shown to be ugly, people having gotten into trouble for what they have said on some web forums. NASA’s logical short term COTS alternative, a capsule on an EELV is thus self-censored.

But all this, even when happening in a good way, won’t change price to orbit significantly or enable real spacefaring.

What You’d Need

You’d need a refuel and go again reusable launch vehicle (RAGA RLV) that has turbopumps. No newspace company has money for that (and they are wisely using their little money on something else anyway). Besides, you’d in any case need multiple X-vehicles to develop the techniques like TPS or launch infrastructure and procedures to maturity so they could be operated with reasonable crew size and consistency. A launcher could be depended upon.

Human societies don’t seem to have capability to demand long term commitment to that technology development.

Environment Analogy

Same with the environment. If oil prices stay above 100 dollars, coal based petroleum will come soon and the synthesis already will produce massive amounts of CO2. New coal plants will be built too to produce cheap electricity to consumers who want it. Earth will change significantly with the resulting temperature rise.

No significant new energy producing or saving technology or international pacts will be seriously considered, never mind put into effect in the next ten years.

P.S. This post was written with the new Firefox 3. Hope it doesn’t muck up during publishing. Happy Midsummer. Looks to be rainy here.

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