The thread for space cadets!

[Crezth]

Disagreeing = acting like an ass munch. Dat hug box.

 

[Symphony D.]

No, I'll own that I was hostile from start to finish, but that's because the point being made was (and is) ridiculous, and dismissal of points on the basis of "expertise" certainly didn't boost my disposition.

 

[Winner]

I personally don't care about anybody's credentials on the internet (for better or worse), but about whether what people say makes sense. It's something all of us could perhaps agree on...?

Considering most of the quote-war above, this sentence from the very beginning is telling:

Considering there's a very long history of large objects requiring assembly in orbit, like ISS or Mir, why would a Mars mission necessarily be a single-lift operation?

Somebody doesn't know what Mars Direct -which Hobbs was SPECIFICALLY talking about - is all about. Zubrin goes on literally for hours explaining how in-orbit assembly adds complexity and risk and basically makes any attempt at human landing on Mars practically impossible. Mars Direct as originally conceived requires a Saturn-V class launch vehicle designed for beyond-LEO launches. This means it has a large, powerful hydrolox upper stage (the "throw" stage) capable of sending very heavy payloads to Mars on a direct, slightly more energetic Hohmann trajectory.

The HAB, i.e. the lander, weighs in excess of 40 metric tonnes by the time it enters Martian atmosphere. It is also big in volume, about 10 metres in diameter, necessitating the use of a booster with a large payload fairing. Currently there is no rocket in service capable of even lifting this to LEO for assembly, much less to actually send it somewhere.

And good luck trying to assemble a RIGID hull and aeroshell in space. All we have done so far was legoing modules together, not building them in space. That would require a much higher level of expertise in orbital construction than we currently possess.

Of course the main issue - that we DO NOT KNOW how to land anything heavier than a tonne on Mars remains. So even if we had a big bad booster, which we don't and we won't for a long time, we still can't just build Zubrin's tuna cans and start colonizing Mars.

The way he glosses over the issue of landing in all of his books that I've had in my hands is telling. It's one of the annoying details he keeps ignoring. And if somebody asks him, he insults them; such as one lady on the SpaceShow, to whom he said "just build bigger parachutes", absolutely ignoring everything she said about the utter impracticality of such a proposal (exponential mass growth of the parachute, physical impossibility of making such a huge parachute (or several huge parachutes) inflate fast enough, the need for a hypersonic parachute capable of withstanding enormous pressures and temperatures without failing, etc. etc. etc.).

That's what kills his credibility in the real science/space community.

 

[Symphony D.]

Somebody doesn't know what Mars Direct -which Hobbs was SPECIFICALLY talking about - is all about.

I've got Entering Space sitting over on a shelf. The technical specifics of his plan are rather secondary to his core point: a set of modular packages designed to save on complexity and mass (e.g., by assembling fuel on-site) is superior and more practicable than a large, single-shot, take everything mission.

Zubrin spends a lot of time then talking about the technical particulars to make his pitch (which was rather revolutionary at the time and so needed some selling), and makes several assumptions about the exact form this hardware will take, and the means by which it needs to deliver, as you articulate. He has his own particular vision of how this should be done that he then vehemently defends against anything he views as threatening it (e.g., Chang-Diaz). That's all true. He gives you a plan. But really he's selling you on a paradigm, not a plan.

It's not hard to see how his plan can be modified in a large variety of ways to fit different on-the-ground realities (e.g., parceling up on HLVs smaller than the Saturn V, assembly in orbit, assembly on Mars, acquisition of HLVs equal to Saturn V, etc). Mars Direct as described by Zubrin is not the only form of Mars Direct that can or does exist; the term is something of a catch-all and has been modified into a variety of forms, including Mars-for-Less and Mars-to-Stay, both of which retain core elements of Mars Direct.

Zubrin may be personally against this or that solution (e.g., assembly in space as opposed to the use of an high-HLV) but that doesn't mean it can't be done, and it doesn't mean his plan is necessarily shoddy for not having specified it nor that his plan or some variation of it isn't possible; the fact we are having this discussion right now is evidence of that. It was this intense lack of imaginative flexibility in interpreting the as-written material that I took extreme issue with.

And good luck trying to assemble a RIGID hull and aeroshell in space. All we have done so far was legoing modules together, not building them in space. That would require a much higher level of expertise in orbital construction than we currently possess.

In the same way as Mercury and Gemini were necessary to gain the experience to do Apollo, I would imagine quite a number of precursor programs would be necessary to seriously go to Mars, instead of simply hopping on rockets and going, with in-orbit construction being one of them, but that's not really here or there.

Of course the main issue - that we DO NOT KNOW how to land anything heavier than a tonne on Mars remains. So even if we had a big bad booster, which we don't and we won't for a long time, we still can't just build Zubrin's tuna cans and start colonizing Mars.

This is a ridiculous argument. The Apollo LM massed 14 metric tons and the difference between Mars and the Moon is 1/6 G. Mars admittedly has a tenuous but notable atmosphere, but that scarcely makes the problem into one Humanity has no clue whatsoever of how to solve.

And if somebody asks him, he insults them

I wouldn't argue Zubrin isn't a jerk. Does Zubrin's plan have flaws? Yes, plenty. Does he gloss over things? Yes, plenty. Is it a totally ridiculous pipe dream worthy of scorn? No, not at all.

 

[hobbsyoyo]

Is that true?

Yes. I've posted pictures of part of the propulsion system for our main satellite in the 'everyday photos' thread. Aside from the main satellite, I'm also in charge of developing a novel propulsion system for a well-known microsatellite platform. I can't go into too many details on that one because we are in the process of filing for a patent on it.

But you know, being 3/4 through an aero degree, developing real satellite hardware, potentially having a patent in my name and interviewing with Orbital Sciences and Aerojet for work on launch vehicles and rocket engines is like, you know, kind of worthless as far as actual rocket science goes.

I'm in the process of replying to the other posts but I had to stop to answer this one right quick.

Well, he said "spare time," which tells me he's either Tony Stark, or playing Kerbal Space Program.

I'm on the university's satellite design team so despite the number of hours I put in and all of the work I've done, I haven't been paid so I didn't want to spin it as a job.

 

[Symphony D.]

But you know, being 3/4 through an aero degree, developing real satellite hardware, potentially having a patent in my name and interviewing with Orbital Sciences and Aerojet for work on launch vehicles and rocket engines is like, you know, kind of worthless as far as actual rocket science goes.

I'm going to take a step back and ask you two serious questions:

1. Do you understand how it might be taken as slightly presumptuous that you are citing work on a very specific and particular niche application in aerospace, i.e., cold jets and satellites, as granting you the authority to speak on aerospace issues that don't particularly have much to do with those technologies?
2. Do you understand how, given you are an undergraduate student who by virtue of your education not being completed would barely rate as an intern at NASA, being referred to as a "rocket scientist" and touting your experience as if you are NASA Flight Director could be extremely grating?

You've accomplished a lot for where you are, and good for you, but you aren't actually very far, and leaning on your credentials when they aren't particularly impressive comes off to me as extremely arrogant. I've had a very hard time taking you seriously as a result of that. Again, I'm seriously asking.

 

[peter grimes]

I don't know, Symphony, I'm much more inclined to take Hobbs seriously on this stuff than most of the other people in these forums. Not to say that they *can't* be better informed, but that would be surprising.

Just read the space threads and you'll see that few people talk about current developments in aerospace as much as Winner and hobbsyoyo - they're both widely read and up to date.

And I'm surprised that you could have mistaken anything he said for implying that he was on the level of a flight director :roll eyes:

 

[hobbsyoyo]

Well, who started the whole appeal to authority crap anyway?

I mean, other than me on page 1.

Well Symphony D did by telling me I don't know what the hell I'm talking about and then continuing to make his points by the tried and true method of ad hominem attacks with a generous helping of the good old strawman.

I'm eating crow for this, but just having an aerospace education doesn't really make one a rocket scientist. Much less an expert on all things space.

I didn't realize Patroklos had gotten under your skin in the 'ask a rocket scientist thread' you started.

But you guys are right, for my second interview with Orbital Sciences next week, I'll be sure to let them know that according to a guy who took some astro observation classes for his astronomy degree I'm a total dunce.

One of your points was that developing a heavy lift vehicle was difficult. It is not. You just confirmed that.

"I can just say you're wrong without refuting your points and that counts."
I will re-summarize them for your convenience:

-Every single booster you mentioned was developed because there was a massive political will to get them done. That political impetus does not exist and will not likely exist again.

-One of the three boosters you mentioned as some kind of great example of a heavy lift boost rocket was far better at blowing up launch pads than actually launching anything. You do realize the N1 never flew successfully, right?

-I also mentioned the only rocket under development of the class that Zubrin's plan specifically called for. It's billions over budget and half a decade beyond it's original finish date but then again heavy-lift is easy guyz it's not like it's rocket science or something.

You're right, economies of scale are totally not a thing in space.

Look, I can quote too mang!

The problem, rather, is budgetary. "I’ll just be very frank with you; we are very concerned about the cost of space launch," says Shelton. Cost growth has been eye-watering. In a May 11 session of the Senate Armed Services Committee, Sen. Jeff Sessions (R-Ala.) pointed out that the new Fiscal 2012 budget contains $9.8 billion to build 23 new EELV boosters. A year earlier, he went on, the plan for the same period called for spending $6.4 billion on 26 boosters. "That’s three less rockets, but $3.4 billion increase in cost," the senator said.

The article talks about the numerous actual difficulties with getting economies of scale in rocketry (and why it historically hasn't happened) but if you cherry-pick it right it totally backs you up.

Oh wait, no, you're wrong again. Also, Zubrin's plan is absolutely rigid and cannot be altered in any way. To even think of altering it is madness and heresy that only the most sick and demented mind can possibly contemplate. Yep.

Says the fanboi. Just like before, you attack points I didn't make in defense of a plan that Zubrin didn't make while outright ignoring points I didn't make. I have even said you could divide up some of the project into smaller payloads but that adds significant costs and complexity. You haven't refuted that with many points that make actual sense from an engineering standpoint but you've done a bang-up job of attacking me personally. So there's that.

Point you can't refute? Ignore it.

So I say that launch vehicle costs are typically a smaller (sometimes much smaller) fraction of total costs in a project and you say "Look! Falcon 9 is like cheap!".

Again: guess how much payloads for complex launch cost?
-Billions of dollars, sometimes tens of billions, compared to hundreds of millions for launch vehicles.

Once you start dividing up payloads into smaller packages, you start adding massively to their r&d costs. Whereas before, you had one module with it's own prop/thermal/structural elements, now you have to engineer separate, redundant systems. Like I said before (that you ignored), how do you plan on integrating these systems on orbit?

-You have docking systems and multiple redundant airlocks and bulkheads.
-You have to have redundant power systems to keep them alive until they've been assembled.
-You have to have separate propulsion/service modules to actually get them to rendezvous.
-You have to have a menagerie of interlinking pipe work and ducts to connect everything together.

With the exception of most of the prop/service modules (which can be dumped after docking), you have to now drag all of these redundant systems with you all the way to Mars. That adds a metric crap ton of mass, which, according to the rocket equation, is going to be a nightmare to deal with. And that's not even considering the enormous cost you are now adding to the project to engineer all of these redundant systems and then make sure they actually work as advertised on-orbit.

Less than the architecture.

What is this even supposed to mean?

Ahem:

Your argument is: "Zubrin only mentioned heavy launch vehicles,

Pardon me for discussing Zubrin's actual plan.

therefore only heavy launch vehicles could possibly be used,

That's not what I said.

heavy launch vehicles are impossible to acquire,

Not what I said.

and going to smaller launch vehicles than the ones envisioned will make the whole endeavor impossible,

Not what I said.

or ridiculously expensive!"

Where exactly have you disproven this point? Where did you even address the specific problems I brought up?

You've been wrong on every single point.

Well yeah, the strawman hobbs you built up has done a crappy job of defending all those points I didn't make.

Gee I dunno how could you assemble a complex object without multi-ton docking assembles I don't

Oh. Oh...

Your article has nothing to do with the issues I was talking about. Nice read though, so thanks.

Apollo CSM/LM totally did hella mechanically stressful maneuvers like aerobreaking and components incorporating simulated gravity environments and such, yeah.

"I'll talk about something else and ignore what you said"

The behavior of a ship under thrust (admittedly depending upon the scale of thrust) is going to necessitate more rigorous construction than that.

^^This was the original point which I countered, which you then changed to "aerobraking and simulated gravity!", without even addressing my point about launch stresses on the payload which are far greater than any expected TMI burn.

But let's talk about 'aerobraking and simulated gravity':
If you move to a modular construction, you wouldn't necessarily have to ensure that every component be able to survive a drop onto Mars. Ideally, you'd build every system you don't need on Mars into modules you could leave on orbit. This would really help with the actual landing as you wouldn't have to decelerate the whole mass.

Of course, this is beyond the scope of your original quote and my response to it but since you've moved the goal post I couldn't help myself.

Yes, you did say it couldn't be done; you've repeatedly inferred his plan is stupid because he recommended a particular pathway into boosting stuff into orbit and you repeatedly refuse to counsel the notion that acquiring a heavy lift vehicle isn't hard or that it could be done through smaller launch vehicles, something you've spent this entire bloody post doing.

Haven't you already said this?

As I already said, your objection boils down to "But he said X, and there is no possible way under heaven that it could be anything but X, because he said X!" Which is not reasonable by any definition of the word. So if I'm strawmanning, you're being exceptionally pedantic and inflexible.

Now I know I've seen this someplace....

When are you going to address what has actually been said instead of wasting time putting words in my mouth?

Let's go back to what you said, once again, since you can't seem to remember:

You're right, I can't seem to keep the points I didn't make straight.

CUTTING UP PAYLOADS IS TOTALLY NONSENSE

Well when are you going to disprove this strawman? I've been waiting for a while, please indulge me.

GUYS HE DIDN'T EVEN MENTION IT

He didn't. I did, but somehow that got lost in all of the ad hominem attacks and ANGRY CAPS.

AND IT'S NOT POSSIBLE IT WILL BE SO EXPENSIVE

Yawn.

Yeah, you're right, I haven't addressed your points at all. You win, hobbsyoyo, it is absolutely impossible to parcel up Mars Direct onto several smaller launch vehicles because Robert Zubrin called for heavy launch vehicles, and therefore the whole thing is a ridiculous sham. You're absolutely right. You are Aerospace and Logic King and I am just a ridiculous troll. Nailed it in one.

What are you on about now? Oh right, the same thing.

Please tell us some more about how making rubber-band driven balsa wood planes (in your spare time) makes you an expert on the B-52. I personally love a good appeal to authority. Perhaps a real rocket scientist who plays Kerbal Space Program can enlighten us some more on this subject.

oh wow acronymagent you caught me okay lets trot out credentials

"I'm going to tell you that you don't know what you're talking about. When other people point out that quite possibly, you do, I'm going to tell you that you've claimed to be an expert in all the things and tell you your real-life experience doesn't hold a candle because I looked in a telescope and tried to avoid looking at a laser beam."

i mean i did observational astronomy as part of a undergrad astro program and worked in a high energy laser lab so obviously I am just as qualified to talk about heavy lift boosters as some guy who fiddles with cold gas jets because we are both totally qualified and knowledgeable experts in our field

ouch

your appeal to authority to a guy who, by the standards of his field, is a know-nothing dime-a-dozen cheap replacement cog barely out of diapers is not both sad and kind of funny

carry on

"I started on the authority appeal by saying you have none. Now I will call you names. Checkmate."

Keep calling an undergrad engineer a rocket scientist and acting like he's the second coming of Werner von Braun then, bro. He will never lead you astray, because you're too busy doing it yourself.


Yeah, keeping the conservation at a level that's intelligible for my audience is hard sometimes, but I try.

"You guys are all idiots"

I've got Entering Space sitting over on a shelf. The technical specifics of his plan are rather secondary to his core point: a set of modular packages designed to save on complexity and mass (e.g., by assembling fuel on-site) is superior and more practicable than a large, single-shot, take everything mission.

Methinks you're confusing his actual 'core point' with what you have been making up on the fly.

It's not hard to see how his plan can be modified in a large variety of ways to fit different on-the-ground realities (e.g., parceling up on HLVs smaller than the Saturn V, assembly in orbit, assembly on Mars, acquisition of HLVs equal to Saturn V, etc).

And yet you've failed to address any of the actual problems with doing that.

Zubrin may be personally against this or that solution (e.g., assembly in space as opposed to the use of an high-HLV) but that doesn't mean it can't be done, and it doesn't mean his plan is necessarily shoddy for not having specified it nor that his plan or some variation of it isn't possible; the fact we are having this discussion right now is evidence of that. It was this intense lack of imaginative flexibility in interpreting the as-written material that I took extreme issue with.

"Someone said something I didn't like. I didn't actually read what they said, but it smelled funny so I'm going to tell everyone what a bunch of kindergarten amateurs you are."

In the same way as Mercury and Gemini were necessary to gain the experience to do Apollo, I would imagine quite a number of precursor programs would be necessary to seriously go to Mars, instead of simply hopping on rockets and going, with in-orbit construction being one of them, but that's not really here or there

This is a ridiculous argument. The Apollo LM massed 14 metric tons and the difference between Mars and the Moon is 1/6 G. Mars admittedly has a tenuous but notable atmosphere, but that scarcely makes the problem into one Humanity has no clue whatsoever of how to solve.

"You make silly points and I'm not going to bother explaining why you're wrong. Just take my word for it."

 

[hobbsyoyo]

I don't know, Symphony, I'm much more inclined to take Hobbs seriously on this stuff than most of the other people in these forums. Not to say that they *can't* be better informed, but that would be surprising.

Just read the space threads and you'll see that few people talk about current developments in aerospace as much as Winner and hobbsyoyo - they're both widely read and up to date.

And I'm surprised that you could have mistaken anything he said for implying that he was on the level of a flight director :roll eyes:

BUT I AM OBVIOUSLY THE KING OF SPACE RESPECT MAH AUTHORITY

I'm going to take a step back and ask you two serious questions:

Do you understand how it might be taken as slightly presumptuous that you are citing work on a very specific and particular niche application in aerospace, i.e., cold jets and satellites, as granting you the authority to speak on aerospace issues that don't particularly have much to do with those technologies?

Niche application? You don't know what you're talking about.

Don't you think it was slightly presumptuous for you to rest your case on 'you don't know what the hell you're talking about' along with a number of ad hominems? I've countered your points and the best you can offer in retort are a laundry list of strawmen and insults whilst ignoring what has actually been said.

Do you understand how, given you are an undergraduate student who by virtue of your education not being completed would barely rate as an intern at NASA, being referred to as a "rocket scientist" and touting your experience as if you are NASA Flight Director could be extremely grating?[/LIST]
You've accomplished a lot for where you are, and good for you, but you aren't actually very far, and leaning on your credentials when they aren't particularly impressive comes off to me as extremely arrogant. I've had a very hard time taking you seriously as a result of that. Again, I'm seriously asking.

You're right, you looked through a telescope that one time so obviously I'm an idiot.

 

[hobbsyoyo]

I don't know, Symphony, I'm much more inclined to take Hobbs seriously on this stuff than most of the other people in these forums.

Seriously though, you're just indulging his rage boner. He started all this ad hominem crap and when people point out that maybe I do know what I'm talking about, he's responded by twisting everyone's words into 'appeals to authority' while continuing to disparage myself and everyone else.

I really appreciate the support from everyone but I don't need it. The guy has spent more time attacking me than he has in actually refuting what I've said and when he does bother to attempt rebuking me, he does it by way of strawman and ANGRY CAPS MISCHARACTERIZATIONS TO THE MAX BRAH. I'm not really worried he's going to convince anyone I'm a dunce.

 

[Masada]

The article talks about the numerous actual difficulties with getting economies of scale in rocketry (and why it historically hasn't happened) but if you cherry-pick it right it totally backs you up.

You, ah, don't seem to have read that quote. Because it makes quite clear that there are huge scale effects in play. The unit cost of 26 rockets is half the unit cost of 23 ($264M v $426M). Symphony D. seems to have been in the right on this.

 

[Symphony D.]

And I'm surprised that you could have mistaken anything he said for implying that he was on the level of a flight director :roll eyes:

When somebody calls out an accomplished and well-known expert in the field who holds a Masters in the field, worked for a major defense contractor, and did things like invent the nuclear salt-water rocket, and that person is described with "Yes, it's true. I wasn't kidding. He's really an actual rocket scientist," I expect more credentials than "I have 3/4 of an undergraduate degree and some companies are looking at hiring me."

I had friends in undergraduate physics, math, engineering, and astronomy. They didn't act like they worked at FermiLab, the Max Planck Society, LLNL, CERN, or JPL when invoking their credentials, and certainly nobody would've looked at those credentials as particularly impressive if they had—because they're not. It bespeaks a certain arrogance, especially when somebody has the gall to pull rank in OT on CivFanatics after making such shoddy arguments. Which I will now address.

But you guys are right, for my second interview with Orbital Sciences next week, I'll be sure to let them know that according to a guy who took some astro observation classes for his astronomy degree I'm a total dunce.

Tell them you waved your uncompleted degree around in an internet slap fight to prove you're an expert on a national mission launch architecture. I'm sure they'll be very impressed by your maturity and reserve.

"I can just say you're wrong without refuting your points and that counts."

You did it first, so turn-about is fair play.

-Every single booster you mentioned was developed because there was a massive political will to get them done. That political impetus does not exist and will not likely exist again.

I would like you to explain to me the circumstances under which a Mars mission is conducted—regardless of how it's run—where it goes forward yet does not have massive political will backing it.

-One of the three boosters you mentioned as some kind of great example of a heavy lift boost rocket was far better at blowing up launch pads than actually launching anything. You do realize the N1 never flew successfully, right?

Almost like some engineers were under the gun and did a shoddy job. Maybe they'd only completed 3/4 of their degrees too.

Look, I can quote too mang!

Yeah, when you go from 26 boosters at $6.4 billion to 23 boosters at $9.8 billion, that would be scales of economy; less units, more cost! Is all of that strictly scales of economy? No. Is some of it? Yes! Thanks for making my point for me.

The article talks about the numerous actual difficulties with getting economies of scale in rocketry (and why it historically hasn't happened) but if you cherry-pick it right it totally backs you up.

Yeah, when you've got a non-competitive monopoly faced with really sketchy purchasing orders it's like they get skittish and jack up the prices screwing up the cost curve. Wait, what was your original point again?

Economies of scale in rocketry aren't as much of a thing as you seem to think.

Oh, right, you claimed none of this was actually important and didn't happen. That's right.

Says the fanboi.

I don't even like Zubrin that much. I way prefer Chang-Diaz. But you:

You're absolutely correct though, he's an idea man more than he is an actual execution-man. As an aside I recently found out that his reputation amongst most engineers/professors in the Aero field is pretty much toilet water. I was told he tries to pass off other people's ideas as his own, mischaracterizes his credentials and is so abrasive that no one wants to work with him but fanbois.

Definitely seem to have an aerospace axe to grind. Also: extreme irony vis-a-vis credentials remark! lol self-awareness?

So I say that launch vehicle costs are typically a smaller (sometimes much smaller) fraction of total costs in a project and you say "Look! Falcon 9 is like cheap!". Again: guess how much payloads for complex launch cost? Billions of dollars, sometimes tens of billions, compared to hundreds of millions for launch vehicles. Once you start dividing up payloads into smaller packages, you start adding massively to their r&d costs. Whereas before, you had one module with it's own prop/thermal/structural elements, now you have to engineer separate, redundant systems. Like I said before (that you ignored), how do you plan on integrating these systems on orbit?

So you're taking one-off, custom-built scientific payload costs using equipment that is usually custom-made to order (jacking up the price tremendously) and you're applying that mission cost metric to something that by its very nature would be mass-produced for continuous launches (into basically perpetuity), aboard mass-produced launchers, after claiming economy of scale wasn't a thing, and then having demonstrated it was.

Sounds legit.

-You have docking systems and multiple redundant airlocks and bulkheads.
-You have to have redundant power systems to keep them alive until they've been assembled.
-You have to have separate propulsion/service modules to actually get them to rendezvous.
-You have to have a menagerie of interlinking pipe work and ducts to connect everything together.

Most of Mars Direct's program calls for inert gear that doesn't need to be pressurized and just needs to be massive enough to do its job on site (produce/store fuel, produce/store water, etc.) or sit idly until astronauts show up, so I don't really know what the hell you're talking about.

Pardon me for discussing Zubrin's actual plan.

Sorry that you couldn't read between the lines as to what a popular-consumption book was actually about.

That's not what I said.

Well you repeatedly bloody returned to it, now didn't you:

It adds drastically to the complexity, mass and cost of the overall system --> which defeats the entire purpose of Mars Direct as envisioned by Zubrin.

I didn't, his plan expressly calls for it.

Even then, it falls well short of the Saturn V type of rocket Zubrin expressly calls for.

(which, for the tenth time, is not what Zubrin called for)

Zubrin said, Zubrin said, Zubrin said, I'm not going to have a discussion about any possible deviations made to a book written for the common man in goddamn 1999, because Zubrin said! Yet you don't understand why you come across as horribly inflexible and unimaginative.

This was the original point which I countered, which you then changed to "aerobraking and simulated gravity!", without even addressing my point about launch stresses on the payload which are far greater than any expected TMI burn.

I'll give you this one, this was a stupid argument on my part.

Well when are you going to disprove this strawman? I've been waiting for a while, please indulge me.

As above, so also below:

---

I want to draw special attention to this, since this is the last cogent point you made before doing a rather poor impersonation of my favorite dismissive style:

I have even said you could divide up some of the project into smaller payloads but that adds significant costs and complexity. You haven't refuted that with many points that make actual sense from an engineering standpoint but you've done a bang-up job of attacking me personally. So there's that.

You said it was possible... and then dismissed it out of hand. And I quote:

You could divide up some of it, for sure. Maybe you could even divide up all of it (though he never mentions this) to fit on smaller rockets. But then your costs sky-rocket (no pun intended) for a whole host of reasons. But he never even mentions is because we have the 'equivalent' of multiple Saturn V launches at our disposal. It's just nonsense

You were then given evidence of the fact that multiple split launches would be cheaper per launch and you again dismissed it out of hand. And I quote:

Apples and oranges.

So yes, I did roundly mock you for being presented the very argument you now claim was never made, only to dismiss it, and for you to now dismiss it yet again. You could perhaps explain to us how, when multiple launches are demonstrably cheaper than an equivalent large HLV, this argument does not hold. Instead, you didn't. You haven't. And if this is anything to go by, you won't.

You went back to your "but it is the payload that is so expensive!" point and completely ignored the fact that multiple launch vehicles are cheaper per launch, and you hinged this dismissal on your (unproven) notion that each individual Mars Direct payload will wind up a very expensive custom hot-rod like Cassini when in actual practice it will be closer to mass-produced construction equipment.

Now that the shoe is on the other foot, I want you to address your strawman, which you have heretofore completely skirted several times.

---

Methinks you're confusing his actual 'core point' with what you have been making up on the fly.

Yeah, you're right, this actual scientist wrote a mass-market book intended for general audiences called Entering Space: Creating a Spacefaring Civilization to lay out his exceedingly precise operational plan and trick the public into demanding NASA execute it despite all its horrible flaws.

You caught him, undergrad.

You saved America from Robert Zubrin.

 

[hobbsyoyo]

You, ah, don't seem to have read that quote. Because it makes quite clear that there are huge scale effects in play. The unit cost of 26 rockets is half the unit cost of 23 ($264M v $426M). Symphony D. seems to have been in the right on this.

There's more too it than that, namely, you have to guarantee big orders up-front. This is something the Air Force hasn't been able to do. Moreover, even bigger savings were expected to be realized back in the 90's when everyone was talking about flying giant constellations of satellites which would drastically have reduced costs. That didn't pan out and now companies like ULA are sitting with massively overbuilt factories that have never come close to the production goals they were slated for. Further, the technology and tooling that was cutting edge in the 90's is somewhat out of date now and Lockheed has been having to close plants and shift production down to Alabama to help contain growing costs associated with keeping idle plants open and keeping talented engineers on the payroll.

So yes, theoretically, you could bring down costs. Unfortunately, as the article pointed out, the opposite has happened and the costs have continued to climb for all the reasons listed above. Finally, as I've been saying all along, the costs of the launch vehicles is a proportionally small part of total project costs. For something like a manned mission to Mars using medium-lift vehicles, your costs will absolutely be dominated by the payload itself, not the lift vehicles if you use existing rockets and don't develop the kinds of super-heavy lift vehicles that Zubrin expressly calls for.

When somebody calls out an accomplished and well-known expert in the field who holds a Masters in the field, worked for a major defense contractor, and did things like invent the nuclear salt-water rocket, and that person is described with "Yes, it's true. I wasn't kidding. He's really an actual rocket scientist," I expect more credentials than "I have 3/4 of an undergraduate degree and some companies are looking at hiring me."

->Guy on the internet has an opinion on the internet you don't agree with
->Attack him personally and repeatedly while disparaging his credentials
->Tell people who defend him that they are the ones appealing to authority
->Appeal to Zubrins authority

So we've come full circle.

I had friends in undergraduate physics, math, engineering, and astronomy. They didn't act like they worked at FermiLab, the Max Planck Society, LLNL, CERN, or JPL when invoking their credentials, and certainly nobody would've looked at those credentials as particularly impressive if they had—because they're not. It bespeaks a certain arrogance, especially when somebody has the gall to pull rank in OT on CivFanatics after making such shoddy arguments. Which I will now address.

What the frak are you on about again? Right, you don't think I know anything and putting forward my credentials obviously means I've claimed to be the expert in all the things. Sure thing.

Tell them you waved your uncompleted degree around in an internet slap fight to prove you're an expert on a national mission launch architecture. I'm sure they'll be very impressed by your maturity and reserve.

inorite?

You did it first, so turn-about is fair play.

Yeah, you're going to have to prove that.

I would like you to explain to me the circumstances under which a Mars mission is conducted—regardless of how it's run—where it goes forward yet does not have massive political will backing it.

I'll just show you the number of active humans-to-Mars programs currently under development as proof that their is massive political impetus behind them.

...

Almost like some engineers were under the gun and did a shoddy job. Maybe they'd only completed 3/4 of their degrees too.

So instead of refuting the points that were raised, you attack me again. This is productive.

Yeah, when you go from 26 boosters at $6.4 billion to 23 boosters at $9.8 billion, that would be scales of economy; less units, more cost! Is all of that strictly scales of economy? No. Is some of it? Yes! Thanks for making my point for me.

You've got it backward - we're currently losing the economy of scale because we can't afford and don't have the political will/need to buy as many as it would take to provide economies of scale. Which goes back to my point about them not being as much of a thing because they can't be realistically achieved under current budgetary circumstances. When the government or private industry can pony up to buy more than a couple dozen boosters, then you'd have a point. But they can't and won't, so costs have climbed and the way the industry works, it will be hard to get those lower prices back unless and until you can buy massive numbers of rockets to offset the cost of retooling factory lines that have been closed, opening entire closed factories and rehiring laid-off engineers.

Yeah, when you've got a non-competitive monopoly faced with really sketchy purchasing orders it's like they get skittish and jack up the prices screwing up the cost curve. Wait, what was your original point again?

Right, so the rocket industry doesn't work exactly like <random widget producing> industries, which is exactly my point.

Oh, right, you claimed none of this was actually important and didn't happen. That's right.


I don't even like Zubrin that much. I way prefer Chang-Diaz. But you:


Definitely seem to have an aerospace axe to grind. Also: extreme irony vis-a-vis credentials remark! lol self-awareness?

So when exactly are we going to talk about the actual issue?

So you're taking one-off, custom-built scientific payload costs using equipment that is usually custom-made to order (jacking up the price tremendously) and you're applying that mission cost metric to something that by its very nature would be mass-produced for continuous launches (into basically perpetuity), aboard mass-produced launchers, after claiming economy of scale wasn't a thing, and then having demonstrated it was.

Sounds legit.

That's what you don't get - everything is custom order in the space industry; nearly all large payloads cost a ton of money. Hypothetical man-mars mission hardware is certainly no exception in this regard. See above regarding launch vehicle costs.

Most of Mars Direct's program calls for inert gear that doesn't need to be pressurized and just needs to be massive enough to do its job on site (produce/store fuel, produce/store water, etc.) or sit idly until astronauts show up, so I don't really know what the hell you're talking about.

Well you wouldn't know because it's easier to hand-waive away the issues I've raised rather than addressing them. So I believe you when you say you don't know what the hell I'm talking about.

Sorry that you couldn't read between the lines as to what a popular-consumption book was actually about.

Right, because that one book is the only place he's laid out in detail his plans.

Well you repeatedly bloody returned to it, now didn't you:

Where did I say it couldn't be done? Oh wait, I said it could be done before you ever even showed up. Right then.

Zubrin said, Zubrin said, Zubrin said, I'm not going to have a discussion about any possible deviations made to a book written for the common man in goddamn 1999, because Zubrin said! Yet you don't understand why you come across as horribly inflexible and unimaginative.

We've been talking about Zubrin's plans (which are not fully encompassed by one book), so what's your point? You've raised alternatives which expressly go against his plans. I'm happy to entertain your alternatives and I've tried discussing them. It hasn't gotten much further past the 'neener neener stupidface!' phase of the discussion though.

You said it was possible... and then dismissed it out of hand.

Oh sure, I didn't elaborate at first but I've gone to great lengths to discuss the issues with you. When are you actually going to address the problems I've raised?

And I quote:

Out of context, but okay. There I was specifically talking about he deliberately mixed apples and oranges. He claims you need a couple of Saturn V class vehicles per year for his plan. He then states that the capabilities they would offer represent a small fraction of the US total heavy-lift capability. My point was that's a bogus comparison - we have no launchers of the Saturn V class so unless you can cut up the payloads for smaller rockets, then you can't lift any of it. Given that he's expressly against this idea and that his idea was the one I was discussing, it's fair to characterize his point as bunk.

Now you've come in and talked about cutting up the payloads and even though I've agreed in principle it could be done, there are still lots of issues with it - Issues which you've hand-waived away or ignored. In any case, you're continuing to come back to attack my characterization of Zubrin's own arguments by making arguments that he hasn't only not made himself, but has actually spoken against.

You were then given evidence of the fact that multiple split launches would be cheaper per launch and you again dismissed it out of hand. And I quote:

I have gone into detail on the subject and how splitting up the launches could end up driving up total costs. Where again did you refute the specifics of my points?

So yes, I did roundly mock you for being presented the very argument you now claim was never made, only to dismiss it, and for you to now dismiss it yet again. You could perhaps explain to us how, when multiple launches are demonstrably cheaper than an equivalent large HLV, this argument does not hold. Instead, you didn't. You haven't. And if this is anything to go by, you won't.

You have proven anything because you've avoided my points. It's like talking to a brick wall with attitude.

You went back to your "but it is the payload that is so expensive!" point and completely ignored the fact that multiple launch vehicles are cheaper per launch, and you hinged this dismissal on your (unproven) notion that each individual Mars Direct payload will wind up a very expensive custom hot-rod like Cassini.

I haven't ignored anything, do try and read my posts.

Now that the shoe is on the other foot, I want you to address your strawman, which you have heretofore completely skirted several times.

Which one is that?

 

[hobbsyoyo]

I'm headed into the lab. Please continue to disparage me while I'm out.

 

[bhsup]

Okay! Your mother is a hamster and your father smells of elderberries!

 

[Symphony D.]

There's more too it than that, namely, you have to guarantee big orders up-front. This is something the Air Force hasn't been able to do.

Continually ignores the fact this is precisely the goal of Mars Direct given its whole MO is to launch vehicles and payloads more or less continually with no stated end mission date...

Moreover, even bigger savings were expected to be realized back in the 90's when everyone was talking about flying giant constellations of satellites which would drastically have reduced costs. That didn't pan out and now companies like ULA are sitting with massively overbuilt factories that have never come close to the production goals they were slated for. Further, the technology and tooling that was cutting edge in the 90's is somewhat out of date now and Lockheed has been having to close plants and shift production down to Alabama to help contain growing costs associated with keeping idle plants open and keeping talented engineers on the payroll.

So yes, theoretically, you could bring down costs. Unfortunately, as the article pointed out, the opposite has happened and the costs have continued to climb for all the reasons listed above. Finally, as I've been saying all along, the costs of the launch vehicles is a proportionally small part of total project costs. For something like a manned mission to Mars using medium-lift vehicles, your costs will absolutely be dominated by the payload itself, not the lift vehicles if you use existing rockets and don't develop the kinds of super-heavy lift vehicles that Zubrin expressly calls for.

"Economies of scale don't work ever because USAF reneg'd on the agreement directly subverting the anticipated economies of scale! Obviously the efforts at bringing down costs caused them to go up, not the failure to drive demand in the market which would have been difficult to anticipate at the time!"

->Guy on the internet has an opinion on the internet you don't agree with
->Attack him personally and repeatedly while disparaging his credentials
->Tell people who defend him that they are the ones appealing to authority
->Appeal to Zubrins authority
So we've come full circle.

More like guy who flaunts supposed authority has pattern of attacking authority of others while appealing to his own, is called on it repeatedly, claims hypocrisy.

What the frak are you on about again? Right, you don't think I know anything and putting forward my credentials obviously means I've claimed to be the expert in all the things. Sure thing.

But you know, being 3/4 through an aero degree, developing real satellite hardware, potentially having a patent in my name and interviewing with Orbital Sciences and Aerojet for work on launch vehicles and rocket engines is like, you know, kind of worthless as far as actual rocket science goes.

"I work on fancy gas release valves but somebody might hire me to do grunt work on boosters so let me tell you how qualified I am to talk about boosters."

Yeah, you're going to have to prove that.

Whole "special attention" section broski, maybe try reading the posts in full.

I'll just show you the number of active humans-to-Mars programs currently under development as proof that their is massive political impetus behind them.

This... contradicts... what I said... how? Yeah, there's no Mars mission underway, so there is no political impetus, and no large boosters. You seem to think a Mars mission might occur and yet the impetus for large boosters will "not likely exist again." You still have yet to address that contradiction.

So instead of refuting the points that were raised, you attack me again. This is productive.

I see an ice burn on somebody who spent half his post being a jerk back, I take it. Don't be tryin' to play Mr. High Road at this junction.

You've got it backward - we're currently losing the economy of scale because we can't afford and don't have the political will/need to buy as many as it would take to provide economies of scale. Which goes back to my point about them not being as much of a thing because they can't be realistically achieved under current budgetary circumstances. When the government or private industry can pony up to buy more than a couple dozen boosters, then you'd have a point. But they can't and won't, so costs have climbed and the way the industry works, it will be hard to get those lower prices back unless and until you can buy massive numbers of rockets to offset the cost of retooling factory lines that have been closed, opening entire closed factories and rehiring laid-off engineers.

Yo dawg, I'mma lay this out real simple like for ya:

• Implementing Mars Direct means committing to launches basically forever for it to make any sense at all.
• This means there will be hella lots of payloads.
• Breaking these payloads up into smaller units on more launchers means hella hella lots of launchers.
• This also means hella lots of payloads.
• These are basically mass volumes of all kinds of components for the contractors who score their production in a basically open-ended, guaranteed contract with whoever is footing the bill.
• That means supplies go hella hella hella up.
• That means costs go hella hella hella down. See also: ULA supplies glut, 1990s, which you consistently misinterpret somehow.

This is like, ECON 101, your field is not some pretty special snowflake that ignores all market forces just because it has historically operated on a terrible aftermarket custom car model to-date, particularly in the event something extraordinarily lucrative like Mars Direct came down the pipe.

Right, so the rocket industry doesn't work exactly like <random widget producing> industries, which is exactly my point.

Yeah gee maybe that is why it's horrible and fostering outside competition is smart, to say nothing of foreign national products, which a huge open-ended contract would inevitably draw and spark competition for.

So when exactly are we going to talk about the actual issue?

Oh, I'm sorry, I was dealing with a tidal wave of your misdirection. Maybe don't put it there next time?

That's what you don't get - everything is custom order in the space industry; nearly all large payloads cost a ton of money. Hypothetical man-mars mission hardware is certainly no exception in this regard. See above regarding launch vehicle costs.

That's what you don't get, and I'mma bold and size this so you can see it through your myopia, because this is like the core freakin' argument and it's somehow not getting through:

The whole point of this mission architecture is to industrialize and routinize interplanetary flight to get away from that paradigm.

Well you wouldn't know because it's easier to hand-waive away the issues I've raised rather than addressing them. So I believe you when you say you don't know what the hell I'm talking about.

For someone so fixated on What Zubrin Said you sure weren't paying attention to the whole thing about getting bits and bobs to Mars unmanned.

Right, because that one book is the only place he's laid out in detail his plans.

hobbsyoyo returns to the argument that Zubrin wrote a techspec white paper to the people of America to get them to democratically vote for his plans, rather than to do an end run around an entrenched bureaucracy that has always favored all-in-one mission plans and get his idea out in the public eye.

Where did I say it couldn't be done? Oh wait, I said it could be done before you ever even showed up. Right then.

Yeah you're right casting very disparaging terms and immense skepticism onto a thing is not damning with faint praise, golly gee.

We've been talking about Zubrin's plans (which are not fully encompassed by one book), so what's your point? You've raised alternatives which expressly go against his plans. I'm happy to entertain your alternatives and I've tried discussing them. It hasn't gotten much further past the 'neener neener stupidface!' phase of the discussion though.

Says the guy whose entire MO is to ignore all points raised and affect a "Heh, stupid Zubrin fanboi" posture. Yeah, sure.

Oh sure, I didn't elaborate at first but I've gone to great lengths to discuss the issues with you. When are you actually going to address the problems I've raised?

Now you're just willfully intransigent and not reading in full.

Out of context, but okay. There I was specifically talking about he deliberately mixed apples and oranges. He claims you need a couple of Saturn V class vehicles per year for his plan. He then states that the capabilities they would offer represent a small fraction of the US total heavy-lift capability. My point was that's a bogus comparison - we have no launchers of the Saturn V class so unless you can cut up the payloads for smaller rockets, then you can't lift any of it. Given that he's expressly against this idea and that his idea was the one I was discussing, it's fair to characterize his point as bunk.

Now you've come in and talked about cutting up the payloads and even though I've agreed in principle it could be done, there are still lots of issues with it - Issues which you've hand-waived away or ignored. In any case, you're continuing to come back to attack my characterization of Zubrin's own arguments by making arguments that he hasn't only not made himself, but has actually spoken against.

Your interpretation is that to cut most of those payloads up, you would need to then assemble them in Earth orbit in some fashion before pushing them onto Mars (which Zubrin is against, yes).

It has literally never occurred to you despite the several times I've all but said it that you can split the payloads up without doing that, has it? Instead of boosting whole cargo containers full of crap to Mars, you boost stacks of palettes or individual palettes instead. There is admittedly a limit to how much you can break down but those items are likely to be very limited if they exist at all and we discussed this in our very first exchange for christsakes, how hard is it to understand?

I have gone into detail on the subject and how splitting up the launches could end up driving up total costs. Where again did you refute the specifics of my points?

I see your "could" and refer you to my simplified ECON 101 about how this is almost certainly bogus.

You have proven anything because you've avoided my points. It's like talking to a brick wall with attitude.

You're deliberately not listening to them.

 

[illram]

Moderator Action: Clearly, folks in this thread have the credentials to have an interesting discussion. However the "interesting discussion" part seems to be missing in the past few pages. Can we get that back on track, lower the hostilities, and limit the walls of quotes? If not the thread could use a breather.
Please read the forum rules: http://forums.civfanatics.com/showthread.php?t=422889

 

[hobbsyoyo]

"Economies of scale don't work ever because USAF reneg'd on the agreement directly subverting the anticipated economies of scale! Obviously the efforts at bringing down costs caused them to go up, not the failure to drive demand in the market which would have been difficult to anticipate at the time!"

That's part of the story. The other (and even bigger part of the story of economies of scale that was barely touched on in the article) was the near-collapse of the launch market in the 90's. A lot of companies began soliciting the kinds of satellite constellation fleets that have never been seen before or since. They even began placing orders with launch vehicle manufacturers who then ramped up their own production capacities. The Air Force was also continuing to make large purchases of satellites as well.

This was in the time period after NASA more or less stopped using launching satellites on the Shuttle and at the same time that the first round of really severe ITAR restrictions went into effect --> the net effect was to artificially funnel more sales towards US launch providers. So there was a ton of optimism in the industry and everyone was gearing up for serious business.

Then traditional internet connections via telephone and cable wires took hold and seriously undercut companies that were planning to build up satellite-internet networks. Likewise, traditional cell phone coverage spread rapidly across the country which undercut companies that planned on building satellite-cellular networks. These two services represented a pretty big chunk of all of the planned satellite constellations and once the companies that planned on offering these services saw their business cases erode, they began folding or drastically cutting back on their orders.

The knock-down effect was enormous because the launch providers had already begun their massive build-up of production capacity and were offering fairly low launch costs due to the high volumes. Once significant orders or portions of orders were cut, the whole house of cards began collapsing. The launch vehicle providers, newly saddled with overbuilt production capacity, couldn't continue offering the same competitive costs that they had been quoting. The rest of the constellation operators struggled under the rising costs and were forced to cut orders, which drove up costs, which in turn caused more cancelations until the vicious cycle had driven a lot of satellite-service providers bankrupt as they couldn't afford to buy the constellations needed to provide their services. In turn, new entries in the launch-vehicle market were similarly driven out before they could establish themselves (which would have surely driven down launch costs).

That's the backdrop of the article you posted and the article also mentions how the
Air Force has benefitted from a surplus of parts left over from the build-up in the 90's. That surplus has come to an end, which has contributed to raising costs.

Masada pointed out that a cut of just 3 orders resulted in a massive increase in cost and holds that this represents economy of scale. The problem with that thinking is that it doesn't actually work backwards as it would with just about any other industry. Ordering more rockets might result in some cost reductions and the
Air Force is certainly looking at trying to guarantee a minimum number of orders to at least keep costs from driving up drastically. But you are not going to see (under present conditions) the kinds of reductions that are the opposite of the rise that is associated with the example of ordering 3-less rockets.

Those prices benefited from surplus parts that no longer exist. Ordering more rockets means not only do you have to produce more rockets from scratch, you would have to restart a lot of production lines to produce components as the launch vehicle providers have been shutting down production plants that were previously idled. So there is going to be massive up-front costs associated with any ramp-up in production which would temporarily offset any economy of scale. Further, there are some absolute limits that will take enormous political and economic costs to overcome.

Consider the Atlas V rocket, which currently accounts for roughly one-half of the proven, reliable stable of American launch vehicles. The Atlas V uses Russian-built RD-180 engines which trace their lineage all the way back to the NK-15 engines developed for the ill-fated N-1 rocket. Currently, RD-Amross (the American/Russian joint consortium that provides RD-180 engines to ULA for the Atlas V) can only guarantee less than 10 engines per year. As reported recently in Space News, there are numerous quality control and volume issues associated with the Russian plant that produces the RD-180's. They can't turn out many more engines per year without significant investment. More importantly, the Russian government has also repeatedly threatened to cut off the export of RD-180's in protest of various disagreements between our two governments. All together, this means the current production rate of Atlas V rockets cannot be significantly increased over current levels and to further complicate the issue, Orbital Sciences has sued ULA over their nearly-exclusive agreements with RD-Amross for access to the RD-180 engine as Orbital Sciences wants to use the engines for their Antares rocket.

RD-Amross does have a license to produce the RD-180 engine in the United States but this too presents complications. There are no plants set up to produce these engines in the US, so to do that you would immediately have to set up production facilities which will drive up costs in the short-term. In the long run, the American president of RD-Amross has stated that producing the engine in the US will cost ~50% more than it would in Russia due to higher labor costs and this is aside from the costs associated with setting up new production facilities.

Now back to the cuts in production facilities that the industry has undertaken. Lockheed, for example, has recently decided to close one of their Colorado rocket plants and consolidate production at a ULA facility in Alabama. While this means that in the long-run, some cost containment can be achieved, it also means that ULA will be faced with hard limits on how many rockets they can produce - and this is in addition to the inability to secure more RD-180's. So yes, you could order more rockets and that would help keep costs down, but again, this only holds so far and you're never going to see the kinds of costs that benefited from surplus parts and excess productive capacity.

Lastly, there are two other issues that have acted historically and presently to defeat the realization of economies of scale that everyone wants. The first of these issues is legacy costs associated with old labor. The late 70's and early 80's were comparatively lean years for the American aerospace industry. This meant that a lot of older engineers clung to their jobs if they survived lay-offs and new, younger engineers were discouraged from entering the job market. So now virtually the entire industry is saddled with an older workforce which commands high salaries due to their enormous experience and/or union contracts. Now that they are beginning to retire en masse, they present new costs in the form of pension/healthcare obligations and have created a shortage of labor which in turn drives up salaries for young engineers. The other problem that has been a major defeater of economies of scale is the inability for the market to demand the kind of consistently high volume that would enable long-run savings. As I have demonstrated, the kinds of boom-bust cycle that happened in the 90's (and this was not a unique event though it was enormous) has contributed to massive miss-matches between supply capability and demand and managing this miss-match has artificially inflated costs.

tl;dr summary:
-Production capacity is currently limited due to things such as engine shortages and plant closings
-There is not a large enough (and just as important, consistent) demand that would drive down costs from either the government or private industry
-Declining rocket orders have increased costs, but increasing rocket orders will not result in equivalent decreasing costs and will likely in fact result in short-term price increases due to structural problems with the industry
-High labor costs are not likely to subside and will likely continue to increase in the short-term which further drives up costs
-The American launch industry doesn't work like most other industries (due to the problems listed above) and economies of scale, while theoretically possible, haven't actually been much of a thing


To counter your other points that are specific to Mars Direct -

You seem to have this misconception that just because Mars Direct would call for a non-ending order of rockets and payloads that this will drive down costs. In Zubrin's version of the plan, essentially two heavy-lift launches are called for per year for an indefinite period. This does not represent high volume by any stretch of the imagination.

For one thing, as I've stated before, you'd have to develop the kind of heavy-lift rocket of the Saturn V class to pull his version of the plan off. Currently, the only kind of rocket in development of this class is the Space Launch System, which as noted, is years behind schedule and billions over budget. It will also be a very expensive rocket to operate but even so, with a guaranteed number of launches (and with R&D costs paid for by the US government), launch costs can be contained though they will still be significant. You cannot say the same about relatively low costs for the payload.

Any manned system requires an enormous amount of effort and resources to develop. Zubrin's plan calls for the deployment of systems that haven't actually been tested and verified in the real world such as in-situ resource utilization (lab testing =/= successful Mars deployment), on-Mars refueling and mobile nuclear power generating rovers of the kilowatt class (which is fundamentally different than the kind of RTG that Curiosity employs). Even if we were very optimistic and assumed that industry could handle the task of developing and verifying all of the systems required more efficiently than NASA could, it still won't be cheap. And that's just the R&D side of the project!

On the production side, you're going to have to set up dedicated facilities to produce/test the hardware. As I've stated before, nearly everything that's built in space is custom order - you can't easily commandeer other production lines to make Mars Direct hardware. Physically, you might be able to occupy a previously built building, but you can't reasonably expect to re-use tooling from other projects. So right from the get-go, you have massive up-front costs you have to sink into the project both in R&D costs and initial production set-up costs.

The volume of essentially two vehicles a year also isn't going to net you any massive savings. It would help if you could guarantee a steady production, but given the current political and economic climate, having such a guarantee isn't something you can necessarily count on. But even with that assumption, we're talking extremely low volumes of custom, high-end components. This itself will drive up unit costs under any reasonable assumptions and you simply can't get any economies of scale out of this system.

Now to your approach of modular construction-
So let's ignore the arguments Zubrin himself has made against a modular approach and go with your suggestion of breaking the payloads into smaller parts.

Ok, so now you have the issues I've previously mentioned. Namely, each component has to be able to maneuver itself to rendezvous on-orbit. This will cut significantly into the size of each module, which means more costs as you'll have to launch more modules. Next, you have to include things like docking structures to each component which is an entirely redundant feature relative to Zubrin's all-up approach. That's extra dead weight you will have to drag to Mars, which means a larger or more numerous propulsion stage(s), which means more launches, which means more cost.

Each module will also have to have independent power and thermal subsystems to function independently until rendezvous. This is also no small trade-off as again, your cutting into both the useful payload of each component which means more launches and also increasing the mass of the overall system which means more propellant is needed. The rocket equation is a &*%$ and I can't overstate how much this extra mass is going to effect the feasibility of the overall mission and drive up costs.

Then there are the plumbing issues which are also non-trivial. Docking adapters typically don't include many of their own life support/propellant/power hook ups. To use the ISS as an example (which is appropriate given how you've held that up as a great example of how to do this), each modules has to have separate plumbing systems hooked up after docking by the astronauts. This means a menagerie of hoses and duct work that has to be routed around inside the living space of the station to get things like O2 and H20 off of new transport modules (though in the case of air, they can often just open up a valve on the transport and dump the air directly into the ISS's atmosphere, but this is an exception). That adds complications, mass and ultimately drives up cost. You could develop some sort of system that incorporates docking adapters along with hook-ups for power and propellant and any other consumables between modules. But this would be yet another piece of brand new hardware that would have to be developed, test and built at enormous cost.

There are some upsides, however. Namely, these extra redundant systems will provide some extra measure of safety to the crew. Much like the Apollo 13 crew were able to shelter in the LM and make use of its prop/life support systems when their service module blew up, a Mars Direct crew could similarly benefit from redundant electric systems and airlocks that could seal off various sections of the ship in case of emergencies. Also, as I mentioned before, a modular approach could theoretically make the landing itself easier by allowing smaller fractions of the total ship to land while leaving other parts on-orbit.

But the downsides are enormous. Not only are you adding significant mass to the overall ship with the modular approach (and raising costs), you are still faced with fundamental limitations in things like module size. As Winner stated, you simply can't make the modules bigger than a set diameter if you go with the small-launch vehicle assumption. This means more launches and of course fundamental limits on things such as living space and so on.

From the launch vehicle perspective, the volume of launches that a modular approach would need wouldn't significantly drive down rocket costs in and of themselves. Sure, maybe you can hit the 'sweet spot' you've spoken of, but that's not going to make launches cheap. Even still, as I've pointed out time and again, it's payloads that are the biggest portion of launch costs, not the launch vehicles in most cases. Splitting up Mars Direct into smaller modular payloads means you're going to have create a lot of redundant R&D efforts as the modules will mostly have different functions for the overall assembled vehicle even if they come in similar packages. Once again, this drives up costs considerably and I don't think it's reasonable to assume that any of the modules will cost less than the launch vehicles that put them in orbit even when you are cranking them out.

How much do you think GPS satellites costs? Or the Iridium constellation? Later in your post, you try and assert that producing lots of modules will drive down launch costs and module costs. I've disproven the launch vehicle cost part, but one only has to look at the enormous expense of unmanned satellite constellations with identical satellites to see that building a bunch of modules is never going to be cheap. To achieve any kind of savings, you're going to have to build dozens of modules at a time for much more than 2 ships-to-Mars/year. Even then, you might drive down unit costs but your total costs are going to skyrocket. Where is the justification for such an approach when we can't even leverage the political will to create a heavy-lift rocket on time and schedule in the US with NASA? I could go along with the notion of launching a couple of Mars Direct payloads to Mars per year, I think that it's a fundamentally sound idea. But I don't think you're going to see much more than 2 Mars launches per year and even if that were to happen, it would never be a cheap nor benefit from the kinds of economies of scale you would see in other industries for all the reasons I've listed in this wall of text.

I think everyone hopes that SpaceX and Orbital Sciences make a big impact on the launch market and act as a catalyst to drive down prices. In particular, the Falcon 9 Heavy would represent a real game-changer in terms of both capability and affordability and will hopefully point the way to even bigger and more capable rockets from multiple companies in the future. I do not discount the possibility that this will come to pass, but for the purposes of this conversation I've chosen to stick to current realities. I would be happy to debate future developments and their potential impact on both Mars Direct and the general launch industry in other posts.

 

[Masada]

Masada pointed out that a cut of just 3 orders resulted in a massive increase in cost and holds that this represents economy of scale.

It's the textbook definition of scale, dude. Not mine.

The problem with that thinking is that it doesn't actually work backwards as it would with just about any other industry.

Yeah, it does. Go to 26 rockets, costs fall. Cut to 23, costs rise. Scale.

Ordering more rockets might result in some cost reductions and the Air Force is certainly looking at trying to guarantee a minimum number of orders to at least keep costs from driving up drastically.

That's scale right there.

But you are not going to see (under present conditions) the kinds of reductions that are the opposite of the rise that is associated with the example of ordering 3-less rockets.

What's so different about 2012 as compared to 2013?

 

[bhsup]

So what's the news with that PRC lunar lander probe? I heard it achieved orbit. Any news beyond that? Will they be landing it anytime soon?