Transterrestrial Musings

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Now might be a good time for you to outline your preferred approach in a cogent succinct summary in other words what you are "for" instead of what you are "against" -- then again maybe not.

Posted by Bill White at January 14, 2007 10:08 AM

Now might be a good time for you to outline your preferred approach in a cogent succinct summary in other words what you are "for" instead of what you are "against" -- then again maybe not.

Posted by Bill White at January 14, 2007 10:08 AM

Bill

That is easy. David Christensen, fomer co-head of advanced business development at Lockheed Martin, whose career reaches back into the 1950's with Von Braun, came up with the MAX design, that I have placed on the www.nasaspaceflight.com website.

It is the best design out there and is worth discussing at length.

It reaches all of the goals of the Ares program far less expensive than the A1/A5 current design.

Dennis

Posted by Dennis Ray Wingo at January 14, 2007 11:27 AM

> It reaches all of the goals of the Ares program far less expensive than the A1/A5 current design.

No, it is *slightly* less expensive than the current design.

You're still trapped in the mode of thinking NASA just needs to pick the right HLV design.

In the past, you argued for an EELV-derived heavy lifter instead of Shuttle-derived. Now, you're arguing for a Shuttle-derived heavy lifter, but one that is different from Griffin's Shuttle-derived.

All these debates miss the point. NASA does not need ANY new heavy lifter.

Okay, let's accept the Wingo/Zubrin thesis that manned missions to the Moon/Mars can't "wait" for RLVs to be developed.

NASA could do those same missions for less money using existing ELVs and orbital rendezvous, docking, and refueling, rather than developing a new HLV. Contrary to the statements made by Griffin and Zubrin, those are not risky, unproven technologies.

Using existing ELVs would allow NASA to begin lunar missions in the next five years, rather than waiting until the end of the next decade. If returning NASA astronauts to the Moon is really as urgent as you say, you are going about it the wrong way.

if "waiting for the development of an RLV" is unacceptable, then waiting for the development of an HLV should be unacceptable also. It would entail just as much delay but have none of the cost-saving advantages.

Posted by Edward Wright at January 14, 2007 12:48 PM

Bill

1. I have never advocated waiting for an RLV to be built. I was with Bob in the last 48 hours and listened to his latest presentation and neither does he.
2. While I agree that we don't need a heavy lifter, the MAX design is not one unless you add the second set of SRBs.
3. As long as Mike Griffin is administator he is going for a heavy lifter. To think otherwise is a bugfart in the wind. Therefore, the only thing that would sway Griffin is to show a design with a clear commonality to the heavy lifter, just as they are trying to do with the Ares 1.
4. I fully support EELV Atlas V as the CLV. Since neither Mike Griffin nor Scott Horowitz will, except under torture at Guantanamo, it is useless to continue to push that to the current NASA management.

Posted by Dennis Ray Wingo at January 14, 2007 01:23 PM

Dennis, I think you meant Ed.

;-)

Posted by Bill White at January 14, 2007 01:56 PM

Dennis,

Where is Max on Nasaspaceflight? I cannot find it.

Posted by Mike Puckett at January 14, 2007 03:41 PM

> I have never advocated waiting for an RLV to be built. I was with Bob
> in the last 48 hours and listened to his latest presentation and neither does he.

No one said you did. But you and Bob both advocate waiting for a new *E* LV.

If your goal is just to send some astronauts to the Moon or Mars quickly, the best solution would be to design a capsule and lander to fit on existing ELVs.

If your goal is to send astronauts to the Moon or Mars affordably, then RLVs would be the way to go.

Building a new ELV is neither the cheapest approach, the fastest approach, or the lowest risk approach.

> I fully support EELV Atlas V as the CLV. Since neither Mike Griffin nor
> Scott Horowitz will, except under torture at Guantanamo, it is useless
> to continue to push that to the current NASA management.

Forget NASA management. Congress controls the purse strings and has the ultimate power. If they refuse to fund a new ELV, Griffin and Horowitz will have to live with it.

Posted by at January 14, 2007 06:05 PM

We will just have to see how all of this actually works out.

Anyone who claims that they know, does not know.

Dennis

Posted by Dennis Wingo at January 14, 2007 09:11 PM

> We will just have to see how all of this actually works out.

> Anyone who claims that they know, does not know.

Dennis, who claimed to know how everything will work out? That's a red herring.

What we do know is that you're still asking the taxpayers to spend billions of dollars to develop new rockets that will only increase the cost of space transportation.

The question is not whether Mike Griffin or Dave Christensen has the coolest design. The question is why the taxpayers should spend any money to increase, rather decrease, the cost of launch.

Posted by Edward Wright at January 15, 2007 12:45 AM

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Rand,

Look at this amazing "mix" of a Bigelow module and an Orion capsule!!!

http://www.gaetanomarano.it/articles/016_BigelowOrion.html

Gaetano

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Posted by Gaetano Marano - Italy at January 15, 2007 01:46 AM

I hate to say I told you so (OK actually I don’t hate it at all) but this is almost the same comment I posted on this site last time “Direct” was the topic. My comment was basically that the structural considerations were likely wrong.

---- Q&A: ESAS Lead - Dr Doug Stanley (On DIRECT)
“The second less major reason for the performance shortfall is in the assumptions about the amount of propellant that the core can actually hold. Because of geometric and structural considerations, a core vehicle of this diameter cannot hold more than 1.6Mlbs of propellant due to tank clearance issues with the structure required to react SRB loads and thrust structure packaging considerations.”

This is my whole problem with all the internet rocketeers. A lot of things look good and cost less on paper. In the end everyone will find that Lockmart and Boeing HAVE been ripping us off on launch costs, but maybe only to the tune of 30-50%. A nice tune to be sure, but not the triple platinum tune clamed by the internet rocketeers.

Posted by brian d at January 15, 2007 02:45 PM

> This is my whole problem with all the internet rocketeers. A lot of things
> look good and cost less on paper.

Sorry to disappoint you, Brian, but the "Direct Launcher" did not come from Elon Musk or Jeff Bezos. It came from Ross Tierney who, to the best of my knowledge, has never worked for any Internet company.

Not that working for an Internet company would prove anything about his rocket design, one way or another.

Ad hominem attacks are a poor substitute for engineering analysis.

> In the end everyone will find that Lockmart and Boeing HAVE been ripping
> us off on launch costs, but maybe only to the tune of 30-50%.

This statement is so ill-informed that one hardly knows where to begin.

First, no one ever suggested that Direct Launcher is the only way (or even the best way) to reduce launch costs. At least, no one who understands launch vehicle economics.

Second, the problems Stanley talks about (SRB loads, tankage limits, etc.) are specific to the Direct Launch design. They are not common to all launch vehicles.

Third, you pull that "30-50%" figure out of thin air. There is no data in the Doug Stanley quote to support it.

Posted by Edward Wright at January 15, 2007 05:27 PM

We will just have to see how all of this actually works out.

It's pretty obvious now how it will all work out. Billions will be spent, some flags and footprints may occur, and, in the end, not a whole lot of lasting significance will have happened.

The fundamental problem is that going to the moon on the small scale proposed can't lead to much. Real progress is going to have to involve space activities on a much larger scale, with at least thousands of launches. A few crews sent to the moon each year would just be a poor imitation of a real space program.

Posted by Paul Dietz at January 16, 2007 06:49 AM

Edward
Geeez I’ll never understand how my comments are always misinterpreted so badly. I didn’t say that the Direct was an internet rocketeer; I was simply saying it was paper rocket LIKE many of the internet rockets. (Yes, some have taken things beyond paper but they are a long way from Atlas/Delta capability). What that means is that my guess is as good as anyone’s what launch costs might ultimately be.

I disagree that 30-50% was pulled out of thin air maybe a bit rarefied though. I have enough experience with real rockets that I could go to work for any number of rocket makers. I would have to write at least a thousand words to lend some credence to my numbers but still it would be far from proven.

Posted by brian d at January 16, 2007 12:28 PM

> I didn’t say that the Direct was an internet rocketeer; I was simply saying it was paper rocket
> LIKE many of the internet rockets.

Falcon and Goddard are not paper rockets, Brian. They are metal and composite. Goddard has already flown successfully, and Falcon may do so before long.

Your cracks about "paper rockets" are simply ignorant. Numerous people have explained that to you, time and time again. Yet, you continue to make ignorant statements.

> I disagree that 30-50% was pulled out of thin air maybe a bit rarefied though. I have enough
> experience with real rockets that I could go to work for any number of rocket makers.

That's irrelevant, Brian. An ignorant statement from someone with experience is still an ignorant statement.

SpaceShip One reduced suborbital launch costs by much more than 30-50%, compared to expendable suborbital rockets. So, we know that it is possible.

Yet, you "guess" that is impossible to reduce launch costs by more than 30-50%. You say, "my guess is as good as anyone’s what launch costs might ultimately be."

That's true, Brian. Your guess is as good as anyone else's -- which means that it's is worthless.

Guesses don't matter. Real data and financial calculations matter. Those things are noteably absent in your attacks on "internet rocketeers." You're just guessing, and you assume everyone else is guessing, too. We aren't guessing, Brian. We've done the math. We know.

Posted by Edward Wright at January 16, 2007 04:17 PM

>We've done the math. We know.

I can do the math and prove the triangle inequality and “know”. The fact that you make a statement like that about launch costs speaks volumes about your intellect. Tell you what, show me your math, and remember to “know” it must be true 100% of the time, you can’t use averages or statistics, you can’t make estimates of material or labor costs and you can’t guess at launch rates.

>SpaceShip One reduced suborbital launch costs by much more than 30-50%, compared to expendable suborbital rockets. So, we know that it is possible.

Really? So SS1 cost between $20-30M for 3 flights, which means you’re claiming that prior to those flights a launch to ~70 miles cost something like $15-20M each? Wallops offers a number of launch vehicles with 1000 lb capability to 500km for around $1M. I “know” I bought one.

That’s not fair, Wallops is run by the government. There are at least a dozed other locations around the world that offer similar flights for similar cost.

And if you’re going to say "but a person was on SS1" then I’ll then ask you what you were comparing the cost of SS1 to when you said

> “reduced suborbital launch costs by much more than 30-50%”

Posted by brian d at January 17, 2007 11:54 AM

Paul,
The fundamental problem is that going to the moon on the small scale proposed can't lead to much. Real progress is going to have to involve space activities on a much larger scale, with at least thousands of launches. A few crews sent to the moon each year would just be a poor imitation of a real space program.

Wow. I couldn't have said it better myself. While I'm pretty sure NASA is never going to accomplish anything on that scale (by choice), it's also not foreordained that commercial enterprise will get there either. Well, ok, it's probably inevitable at some point, so long as humanity doesn't whipe itself out first. However within the timeframe of interest, it's an open question if the private sector could ramp up to that.

I know that you tend to be a bit on the skeptical side. What do you think the odds are that *anyone* could pull off a lunar transportation system on the scale you suggest would be needed?

~Jon

Posted by Jonathan Goff at January 17, 2007 02:26 PM

> I can do the math and prove the triangle inequality and “know”.

Triangle inequality??? Geometry has nothing to do with this.

The important thing is not whether you can do the math, but whether you do the math. You didn't do any math to support your "30-50%" figure. In your own words, you were just "guessing."

> Tell you what, show me your math, and remember to “know” it must be true 100% of the time,

Nonsense. You're claiming impossibility. You have to show that *your* statement is true 100% of the time -- that *no* rocket can beat current ELVs by more than 30-50%.

I am not claiming impossibility, I am claiming possibility. I don't need to show that 100% of all possible rockets can beat current ELVs by more than 30-50%. I only need to show that at least *one* can do it.

Solving the rocket equation shows that it takes somewhere between 10 and 25 pounds of propellant to put one pound into orbit, for reasonable propellant combinations.

Most reasonable propellant combinations cost less than $1 per pound. That means the propellant cost to put one pound of payload into orbit is ~$10-25 or less.

All mature transportation systems operate at around 3 times propellant costs. (The reason why is left as an exercise to the student.) So, a mature rocket-based transportation system would be capable of putting mass into orbit for ~$30-75 per pound.

Delta and Atlas put mass into orbit for thousands of dollars per pound. The difference between those figures is not 30-50%, as you "guess." It's one to two orders of magnitude.

As the late Dr. Maxwell Hunter used to say, anyone who thinks order -of-magnitude cost reductions are impossible either doesn't understand the rocket equation or doesn't know how much rocket propellant costs. (Actually, there's a third possibility. The person may not understand the relationship of propellant costs to overall costs.)

Since I anticipate another snide comment about "internet rocketeers," let me point out that Max Hunter was developing rockets before the Internet even existed. He was the father of the Delta rocket you're so proud of -- but unlike you, he never thought it was the be-all and end-all. In fact, he was appalled that people were still launching Delta rockets instead of developing something better.

Posted by Edward Wright at January 17, 2007 04:02 PM

Paul: “The fundamental problem is that going to the moon on the small scale proposed can't lead to much. Real progress is going to have to involve space activities on a much larger scale, with at least thousands of launches. A few crews sent to the moon each year would just be a poor imitation of a real space program.”

Not necessarily, if one was instead considering designing and sending a seed instead of the whole tree…

Small teams can achieve a lot, a standing army on the moon does not strike me as sensible.

Yes a much higher flight rate would be nice, but this does not necessitate greater funding. I would say that the fundamental problem is more a lack of a competitive commercial R&D culture than an insufficient scale of funding, as such.

Posted by pete at January 17, 2007 06:31 PM

Not necessarily, if one was instead considering designing and sending a seed instead of the whole tree…

I don't know what you mean here. There is no 'small seed' we could send to the moon that would do anything of much significance.

Posted by Paul Dietz at January 18, 2007 11:42 AM

Well, sending a number of small commercial start up teams to the moon will presumably achieve a great deal more for a great deal less than attempting to send a NASA standing army. I would expect the usual NASA/New Space scale ratios to apply.

Posted by pete at January 18, 2007 05:10 PM

Well, sending a number of small commercial start up teams to the moon will presumably achieve a great deal more for a great deal less than attempting to send a NASA standing army.

I don't presume that at all. It might waste less money, but I very much doubt it could accomplish anything to justify the cost. And it wouldn't provide enough traffic to drive down the cost of getting into space, which is what's holding us back.

Posted by Paul Dietz at January 19, 2007 06:48 AM

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