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For the ISS. The shuttle would transfer unused hypergolics to the ISS propulsion module. ATV as well.

ISS Propulsion Module CAD

http://en.wikipedia.org/wiki/ISS_Propulsion_Module

It was canceled and instead Progress and ATV are used directly for most boosting. Nevertheless the technology could be useful in developing hypergolic propellant depots.

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But is not a real RLV program. It’s just a narrow test for one technology. Hence I think naming it Reusable Booster System Pathfinder is misleading.

Overspecification

They overspecify the problem by requiring a glide landing. Why is it superior to powered landing? At the moment, there’s no clear reason to believe it is! Both need to be developed further to understand their advantages and drawbacks. To my knowledge, there have been only six liquid rocket VTVL prototype manufacturers so far: McDonnell Douglas, JAXA (who was the contractor?), Armadillo Aerospace, Blue Origin, Masten Space Systems and Unreasonable Rocket. Only a few of those have flown to higher than a few hundred meters. The design and operations space is mostly totally unexplored.

Nevermind the large number of other alternatives to boostback. Jon Goff had a recent “lecture series” about these.

I understand that this is just one program, but this should not gain the status of the reusables approach of the air force – stuff like that easily happens.

Master Design Fallacy

They also discard evolution and competition – instead just requiring a single masterfully designed prototype before something operational. Sure, this is much better than starting a multi-billion dollar program without a first lower cost prototype, but nevertheless, it sucks. Somebody brief them on newspace! Rand Simberg, Monte Davis, Jonathan Goff, Clark Lindsey, or one of the numerous people who get it. Or one of the prominent company leaders: John Carmack, Jeff Greason, David Masten.

An Ideal Program

Just specify some boost delta vee points and let companies demonstrate progress towards that. A popup tailflame lander would perhaps give more vertical velocity while some good glider or even a booster that has engines for cruising back could boost far down range to give lots of horizontal velocity. There ain’t a clear winner – there might not even be and multiple approaches would have their uses.

(more…)

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He who controls the [Earth-Moon Lagrange points/Phobos/Deimos/Lunar North Pole], controls the solar system.

Why?

Because in space, it is not the tyranny of distance that sets the rules – it’s delta vee instead.

Since there’s no resistance, traveling large distances just takes longer, but doesn’t necessarily require more propellant. Unmanned craft can take this long trip time just fine. This is completely different from the implicit mental models of everyday life or historical exploration, travels and colonization. Even places that are far away in distance can be close in delta vee, and vice versa.

The Earth-Moon Lagrange (EML) points have really low energy trajectories to all the other places, including low Earth orbit (or Earth re-entry). They’re the crossroads. They’re probably not controllable though, like you can’t control low Earth orbit either, it’s just a figure of speech* to stress their significance.

For example, Phobos and Deimos have really low delta vee needs from EML2. And they have really low gravity. This means that it’s cheap to send stuff to them, but perhaps more importantly, it’s cheap to bring stuff from them. Since a lot of space faring is limited by mass that can be brought to locations, a low energy source of material is a real paradigm changer.

The Lunar north pole’s peaks of eternal light are much closer to Earth, but the Moon is so heavy that it takes quite a lot of propellant to descend to and ascend from the surface. The good constant sunlight is an asset though. The area is limited so this is the best incentive so far for a “race”, though I’m skeptical of that.

This post was written partly inspired by Paul Spudis’ and Clark Lindsey’s talking about the importance of the Moon as an enabler for other stuff – I am somewhat less certain. (On VASIMR and JIMO I can refer to Kirk Sorensen who has good reasons for skepticality – the power to mass ratio needed is huge and that’s the really hard part, yet it’s rarely talked about. Space reactors are much harder than Earth ones because of the cooling problem.)

We must dismiss analogies that do not work, since space is a different medium. We must use completely different planning than for exploration on land or the seas, because of the completely different role distance plays. And we must also plan on advancing from exploration ultimately to infrastructure, colonization and self sufficiency.

*: From Frank Herbert’s Dune of course.

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I do appreciate that the model is so different from Apollo that it takes time and thought to understand what it is about; I did not see it at first myself — but once I got past my preconceptions, I found the logic of this approach overwhelming. This is simply what exploration looks like in a world where the budget doesn’t double for a few years and then halve again. You build a piece at a time and as soon as you can start doing things with the pieces, you do so.

Jeff Greason about the Flexible Path, commenting on Rand Simberg’s superiorly excellent Popular Mechanics piece.

Rand Simberg in the article:

I would claim that in fact, this is the most visionary space policy that the nation has ever had, including Apollo. It finally, forthrightly declares a national goal of large numbers of humanity living off planet, with many of them going on excursions into the solar system, and it harnesses the vital element of private enterprise and competition to make it happen in a way that will drive costs down instead of up.

May I add that yours truly proposed something of a flexible path of his own in 2006, though only for launching.

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NASA’s plans to return astronauts to the moon are dead. So are the rockets being designed to take them there — that is, if President Barack Obama gets his way.

Sayeth Orlando Sentinel.

Haven’t followed NASA’s latest movements. The Augustine panel had some potential but stuff seems to have withered down. The organization seems to be a wannabe monument builder without a job. People might want something more practical than monuments, at least I hope they would. Even when NASA has such huge talent and competence in many areas, it fails to function as a sensible whole in defining strategic human space flight. And then there are the legacy issues. One of which is that of Mike Griffin.

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I just updated the blog title and again just watched the page and the blurb.

It’s when we start working together that the real healing takes place, … It’s when we start spilling our sweat, and not our blood.

It’s a quote of David Hume, my favorite philosopher. I haven’t read his books though. I was reading a Finnish translation of one but it seemed so tedious with the language that I couldn’t bother. So me favouring him is based on the works of others about him.

The quote reminded me of the conflicts that I’m witnessing. The subject line matter needs to be done. At the moment many parts of climate software seem to be science software – written by people in a hurry with little planning, and code that has seen different people adding bits and pieces here and there, making it a big mess. Fortran and supercomputers and all that. Well, most software is a mess. Twenty man years, said MT. That’s a small amount of money considering how much is at stake and even compared to the amount of huffing and puffing efforts around the subject. I am available.

What else needs healing and sweat spilling? Well, quite many things. Including stuff in my personal life.

There are lots of old (sometimes Fortran) code packages hanging around. Nuclear stuff, rocket trajectory calculations, rocket engine chemical/thermodynamics performance… You name it, anything a young man is interested in seems to depend on these archaic pieces of software. So there’s a lot of potential work here but it seems so big for just a lone person to do much on their own free time.

The blog title picture is just some hinge flapped NACA foils simulated with the vortex lattice method in QFLR5. That actually IS a free software project, mostly by Andre Deperrois and uses Mark Drela’s XFOIL for 2D calcs. In the picture, the front wing has NACA 4415 with 6 m span, 1 m chord, 25% chord 15 degree full span flap, and the tail is a NACA 0012 with 2 m span 0.5 m chord, 40% flap or elevator at -15 degrees. Flying at 5 degrees AoA (plus 4 deg to the front wing) and 18.9 m/s, lifting about 2000 N. Absolutely no guarantees about the results.

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Clark Lindsey comments on how Arianespace just raised prices instead of lessening costs. I’m reminded of Rob Coppinger’s recent visit to Kourou, their launch site. It just costs a lot to keep a city going in the middle of jungle, and when that cost must be paid by the monthly rocket flight customers only, it gets expensive per flight.

A lot of ideas have beend expounded on expendable rocket manufacturing and reusable refurbishment costs. But it seems the integration before launch is terribly expensive as well, if not the most expensive part. And the launch control costs as well, as does mission control.

Airports are expensive facilities as well, but they are still cheap per trip since the throughput is large. Though I don’t know how smaller airports manage, if they still need radars, passenger and aircraft services etc…

Anyway, this should be a very important focus. It’s less sexy than the sleek fast machines, but lays the important ground work for space access.

The suborbital trips might be good training and experimentation for this. Virgin galactic seems to opt for grandeur with huge custom facilities, making it into something like a theme park. I do wonder if XCOR’s working on something more modest. This might make a huge difference to their profit margin per flight…

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Merry Christmas everyone!

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Doug Stanley, the notorious ESAS leader has said some strange things (this is his option three, one being Ares I and two Ares V):

Eliminating Ares 1 and 5 and all shuttle infrastructure could save NASA future costs that could eventually be applied towards exploration by significantly reducing the workforce and fixed infrastructure costs. This approach would require “commercial” crew transportation for ISS and exploration missions, and would likely require propellant depots to compensate for the smaller commercial launch vehicles. This was not politically feasible in 2005, but perhaps could be today. Additional detailed cost analysis is required, however, to determine the true cost of a procurement that would require paying for two human-rated capsules and launch vehicles to refine the rather optimistic estimates of the Augustine committee.

Umm. The multi-launch scenario technical analysis in ESAS was a travesty. (One launch pad-> too many delays->multi launch not an option. Hello? And lots of other things, like the unbearable cost of manrating, which suddenly vanished a couple months ago when Doug last spoke…) And now Doug is turning around and saying it might be more politically feasible today? Way to wash your hands! So, politics tolerates more launch delays now? Or politics is sufficiently advanced to launch from more than one pad (or VIF)?

I’ve certainly heard stories from before ESAS of how Doug Stanley had been open minded to commercially launched capsules. So what was this nefarious political influence that caused the ESAS to be so bad and subsequently practically freeze most commercial progress for the next 5 years.

One quite obvious road was clear from day one when shuttle retirement was a real thing in the future: a simple capsule on an EELV for ISS taxi. Those rockets exist and fly and have a history. The sooner development is started, the better, the smaller the gap. You can use that for other purposes as well.

I do agree that more than just the Augustine panel report would be nice.

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Photos of a certain large Soviet ground effect vehicle.

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