Griffin nominated for NASA post - SpaceRef link to testimony

GCNRevenger · 2005-03-16 10:53:17

"If we want a beach head, GCNRevenger, use HLLV to launch a Bigelow/Transhab space hotel and offer free room and board to whoever can get there by private launch from the US.

Musk's man-rated Falcon V would work just fine for this purpose.

Congress & NASA pays for the HLLV one throw hotel and after two dozen guests stay for free, we auction it off to the highest bidder and repay the Treasury."

Haha, dream on. Falcon-V doesn't exsist, and it would barely be able to launch a two-seater capsule, with no fuel for TLI/TEI. And a lander? Please Bill, Falcon-V is intended to be a match for the sissy Delta-II. It would not by any means "work fine."

Those "uniformed folks" will be building things too... specifically, a port of sorts on other worlds, and help build the ships to get there in the process. Make no mistake though, private exploitation of space is not a near-term thing, much groundwork needs to be done, and private industry can't since profit is so far off.

So, to speed things up a little bit, government lays the groundwork for them, as they are not controlled by the profit motive.

BWhite · 2005-03-16 11:09:54

Haha, dream on. Falcon-V doesn't exsist, and it would barely be able to launch a two-seater capsule, with no fuel for TLI/TEI. And a lander? Please Bill, Falcon-V is intended to be a match for the sissy Delta-II. It would not by any means "work fine."

All Falcon V need do is reach LEO Hotel Hilton. No further.

Which is good because it can't. :;):

= = =

So, to speed things up a little bit, government lays the groundwork for them, as they are not controlled by the profit motive.

I agree with this. The issue is "how" to do this best.

Edited By BWhite on 1110993965

SpaceNut · 2005-03-16 11:27:58

So as I see it, if no civilians or tourist industry nor colonization efforts; then we are back to the good ole boys club. IMO we will go a few times then and will stop again only to be left hanging in LEO.

GCNRevenger · 2005-03-16 11:52:06

The little Falcon-V couldn't even launch tourists efficently enough (hardly supplies for them) to any orbiting space hotel. Falcon-V just isn't heavy enough to carry more then two or three people. Even four would probobly require expanding the capsule to impractical dimensions.

No no SpaceNut, first a base is set up with power and fuel factories, then the gov't offers to develop Shuttle-II and let private industry buy copies of it and Lunar RLVs, and let them do whatever on the Moon... a tax break and some liability protection to help sweeten the deal too.

clark · 2005-03-16 12:27:46

What? No, NASA isn't soley a wing of the USAF, thats silly.

True, that would be silly. NASA, along with every other federal government though, is a means to further US national policy and is under the direct requirement of serving national security interests. It is silly to think it otherwise.

Apollo, ISS, the Shuttle, earth monitoring, aeronautical research- all of it serves the national security interests of the US. I'm not a conspiracy nut and I don't need a tin foil hat to point that the inter-agency workgroups have increased their size and scope under Bush. NASA is working more hand in hand with the military and ops security programs to develop critical pieces of hardware for use in pursuing various military related policies in the space control, space access, and launch capabilities.

Yeah, it's good to leverage the various agencies to reduce duplication of effort, but it comes at a cost, and unless one understands how NASA is a piece to serve a larger interest, you will miss the bigger picture.

Trying to understand CEV or VSE in the context of *just* NASA loses perspective and undermines your basic assumptions. It leads to the wrong guesses and the wrong analysis.

NASA is throwing away mostly things that aren't hard science, technology development that doesn't have much near-term payoff, and isn't under the aegis of aerospace that NASA was created for.

NASA is moving towards technology development that has or will have direct results geared towards the needs of other federal agencies and national security. There is less of a push on the academic science and pure research that characterize a morew civilizan oriented space program.

I don't think that it is unreasoanble to assume that NASA's job is to establish "beach heads" on other worlds and help to open the spacelanes to get there.

It is unreasonable because it isn't in their mandate. NASA is charged with increasing our understanding of the earth, our solar system, and the universe. Not to lay groundwork for space bombers.

As for the Falcon V... well, I got a reply back from someone working there. It is being man rated. They are pursuing the Bigelow prize. You do the math. :laugh:

GCNRevenger · 2005-03-16 12:42:52

*Tin foil hat detector alert, beepbeepbeep...*

Does everything NASA does serve the national interest? Sure
Does everything NASA does serve the national security interest? No way

The big picture is that there is no bigger picture... CEV makes no sense at all for the military, nor really does VSE as a whole up until and into the base-building phase or Mars expedition phase.

If "exploration" doesn't include "expansion" by your definition, it soon will by the NASA definition.

Falcon-V = Still vaporware. Nor does it have enough payload capability to handle a capsule much bigger then Gemini. It just can't. Bigelow's space prize is also a joke, a sick joke, given how little it is.

clark · 2005-03-16 12:54:35

Okay GCN, I'll go slowly, use small words, maybe you can catch up.

The big picture is that there is no bigger picture... CEV makes no sense at all for the military, nor really does VSE as a whole up until and into the base-building phase or Mars expedition phase.

Oh, so if NASA is helping DOD subsidize EELV production and procurement, in order to meet national security requirements for two seperate launch options, then well, the VSE and CEV don't help em much, do they?

So if airforce is pursuing their space bomber, under project Falcon, and NASA just happens to throw out similar design specs, VSE and CEV just won't help, right?

If DOD is pursuing the whole SDI concept, with multi-mega watt space based lasers, I suppose NASA research in nuclear power generation in space for VSE has no bearing on the military.

Say what you will, I simply don't care. I've done my homework and I've been right more often than not when it comes to this stuff. And for the record, you don't need much more than an uprated Gemini (they had design specs in the 60's for such a thing) to get 5-6 people to Bigelow's hotel. It won't be comfortable, but the idea is that you go to a space hotel for the comfort.

GCNRevenger · 2005-03-16 13:02:05

"Say what you will, I simply don't care."

Well, that kind of makes it hard to believe you've rationally thought this out then.

Sure having NASA and the USAF both buy EELV helps the military, but that isn't the main reason why NASA would do this, it is simply because it is the most efficent option that can be counted on. Its military bennefit is an incidental side bennefit.

NASA won't be needing Shuttle-II development for a while. Maybe a long while... easily after the Pentagon wants its Falcon intercontenental bomber. VSE isn't going to be a big help to the USAF's bomber program.

Multi-megawatt SBL systems will be almost certainly chemical lasers, not nuclear/electric ones, due to the size of the nuclear system required.

SpaceNut · 2005-03-16 13:03:32

So let me get this right it is okay for Nasa to design a ship and then sell the rights to copy it. Then why was that not the case for Apollo or LEM or perhaps the Shuttle of today?
So far all I see Nasa is for prototyping of these vehicles as research level and not anything that resembles steady state manufactured and robust.

GCNRevenger · 2005-03-16 13:09:23

Patience SpaceNut, one thing at a time...

At the moment, there is no reason for any private company to invest the money to build Shuttle-II. There is no place to fly it to.

The only real destinations that are worthwhile have to be more profitable then satelite launching, which doesn't bring in enough money to justify the >$10Bn development cost for Shuttle-II.

The startup costs for such a "destination" are also so big that no private firm would make such an investment. So, NASA must do it for them... Hence VSE with expendable rockets.

BWhite · 2005-03-16 13:32:51

Griffin has other stakeholders to deal with as well:

Whether any of the Delta or Atlas Evolved Expendable Launch Vehicle options will be acceptable for the CEV manned role remains to be seen.
The Astronaut Office at the Johnson Space Center is not keen on any of these options (AW&ST June 14, 2004, p. 15). The astronauts have taken a position that "human rating should be designed in, not appended on." The Office is calling for an order of magnitude reduction in the risk of fatalities on ascent, and has expressed concern that an EELV--be it Delta or Atlas--may not be safe enough even with upgrades.
"Even with extensive modifications, the EELVs may never achieve a meaningfully higher success rate," the Astronaut Office assessment stated.
Upgrading EELVs "could potentially be as costly as building a new human-rated booster," said the Astronaut Office paper, and still "would place excessive burden on abort mechanisms to save the crew."

http://aviationnow.ecnext.com/free-scri … 2215top]Av Week - Trial by Fire

Welcome to NASA, Michael.

Ad Astra · 2005-03-16 14:08:02

If we can't use the EELV's, what can we we use to launch the CEV?

At this point we have no realistic alternatives. Developing a new booster with man-rating in mind from the getgo will take more years and more billions. An SRB-based rocket would be even more unsafe than the EELV's, lacking first-stage thrust termination and having even higher accelerations than the EELV's.

If the NASA astronaut office wants a safer vehicle, they should learn to accept EELV + CEV for what it is, as it will certainly be safer than the shuttle monstrosity.

GCNRevenger · 2005-03-16 14:31:59

I agree Ad Astra,

The EELVs are really the only rockets that can do the job and be safe enough for manned flight. The SRB launcher is a neat idea, but the inherint lack of safety from very large solid rocket engines pretty much dooms this option. Astronaut Office silly pontificating about how "EELVs wern't intended" for people is nonsense, there is nothing special about a rocket that is designed for people.

The #1 "scarry thing" that could happen during launch is that the engine would come apart and explode. With a solid fueled engine, there would be little in the way of warning, and even if you did detect impending failure, there wouldn't be anything you could do to stop it.

Building a brand new rocket just for the crew is obviously not going to happen, it cost several billion to develop the EELVs, which NASA is not going to spend if it can just modify the exsisting EELVs.

My worry is that none of the EELVs can lift the 20MT CEV with its TEI stage on only a single core without SRMs. Delta is definatly out, it doesn't have the capacity, and I think it is questionable if Atlas-V could do this. Would using a small number of little SRMs be acceptable? Or would it be a better idea to launch the TEI stage seperatly? ...Perhaps modify the SRMs such that they can be ejected while running, and tailor them to "fail" away from the vehicle.

I also have to wonder if the astronaut office is trying to save the Shuttle Army by insisting on a "new" (the Thiokol SRB booster) booster.

BWhite · 2005-03-16 15:40:19

EELV to lift CEV makes sense.

"EELV only" means Moon-Mars is false advertising.

Ad Astra · 2005-03-16 17:08:30

I'm in total agreement with BWhite. We may be able to avoid an HLLV for the lunar return but it's a must for Mars. Because we're delaying Mars beyond 2030, maybe we'll find the money to develop and build a clean-sheet HLLV.

The other obstacle I forsee in getting to Mars is what Robert Zubrin calls "the lunar siren." Unlike Zubrin, I believe there is much to be gained from going to the moon. But Mars is also a priority once the technology is mature enough for humans to go safely.

The key will be a smooth transition from our lunar exporation program to Mars exploration. The easiest way to do this, in my view, is to involve private enterprise in the lunar retrn from the start. The moon base operation will be gradually privatized as NASA gears up for Mars. If this doesn't happen, we will have to either abandon the moon, or stick with the moon and forget about Mars.

Michael Bloxham · 2005-03-17 02:21:02

Will Griffin have the power as chief to scrap the shuttle? Might it be possible to speed development of the CEV, and launch it, with ISS payloads, on a quickly adapted SDV? If it could be done, this would certainly be a good start to the Moon-Mars program. A good compromise which should satisfy everyone, no? ???

Nah...

Michael Bloxham · 2005-03-17 02:40:07

I correct myself; reading through his quotes, it seems he doesn't want to keep the ISS. Really? Yippeee! Ahh, maybe he could use the ISS as an excuse for developing an SDV-HLLV, as a replacement for the shuttle fleet, knowing full well the ISS will be old and degrading by the time the SDV is finished, then quick start an HLLV-reliant Moon-Mars program. Sneaky. :;):

John Creighton · 2005-03-17 09:46:52

I am unclear why a vehicle that can lift 45 metric tons would be sufficient for the moon and insufficient for mars. It takes more delta V to for from earth to the moon, then it does from earth to Mars. Also the Moon is a harsher place. If people want to stray there for more then a week or so they will need earth moving equipment to dig in. Finally life-support will be more of a challenge on the moon since the moon does not have an atmosphere to replenish lost gases. Is it possible the vehicle that takes us back to the moon must be equally capable as the vehicle that takes us back to mars?

BWhite · 2005-03-17 10:48:11

I am unclear why a vehicle that can lift 45 metric tons would be sufficient for the moon and insufficient for mars. It takes more delta V to for from earth to the moon, then it does from earth to Mars. Also the Moon is a harsher place. If people want to stray there for more then a week or so they will need earth moving equipment to dig in. Finally life-support will be more of a challenge on the moon since the moon does not have an atmosphere to replenish lost gases. Is it possible the vehicle that takes us back to the moon must be equally capable as the vehicle that takes us back to mars?

Michael Griffin put it this way in Congressional testimony (paraphrased) lunar exploration using medium lift only may be feasible, "but its silly"

This is not Bill White's opinion. Michael Griffin said it to Congress. (Link later when I have time to chase it down - - but it can be found earlier in the thread)

The difference between going to the Moon with medium lift and Mars with medium lift is the magnitude of on orbit assembly that is required.

At best medium lift would support short duration luanr sorties. Not extended presence. Mars requires an extended presence mission, with at least one year spent in deep space travel.

Given the danger of solar flares, an "EELV-only" lunar sortie would always be a gamble. After all, a solar flare would have fried any of the Apollo missions. Therefore, "EELV only" can support scouting sorties but no extended presence.

John Creighton · 2005-03-17 11:05:28

Given the danger of solar flares, an "EELV-only" lunar sortie would always be a gamble. After all, a solar flare would have fried any of the Apollo missions. Therefore, "EELV only" can support scouting sorties but no extended presence.

Well, if this is true then I can’t except the VSE. Still if the EELV can lift 45 MT then three EELV would deliver the same mass to LEO as one of the vehicles Zubrin suggested for Mars direct. Given that the oxidizer can be launched in the third launche and that the EELV’s can be produced fairly quickly and launched fairly quickly, I still don’t see why the EELV can’t do it if Zubrin’s vehicle can.

BWhite · 2005-03-17 11:47:46

Zubrin has said he is agnostic about choice of HLLV. Upgrade Delta to 45 - 50 MT and isn't that an HLLV?

If you can do that with lithium alloys and RL-60 upper stages and keep the three core base to avoid the need for a new pad and Boeing VAB and do it cheaper than SDV, well okay then. . .

But can you?

John Creighton · 2005-03-17 12:00:52

Zubrin has said he is agnostic about choice of HLLV. Upgrade Delta to 45 - 50 MT and isn't that an HLLV?

I’m not sure if it is or not but I can’t possible image any kind of lunar or mars program without at least that much capability.

If you can do that with lithium alloys and RL-60 upper stages and keep the three core base to avoid the need for a new pad and Boeing VAB and do it cheaper than SDV, well okay then. . .

Well, there will be a competition for who can put forth the best design. Perhaps NASA should stipulate in the requirements that the vehicle should be able to lift at least 45-50 MT without any launch pad modification. Perhaps pad modifications could be allowed if the vehicle can lift triple this.

But can you?

Well, lets see what the teams put forth as proposals. Lets hope the president makes a sensible choice and lets hope the vehicle can lift at least 45-50 MT if not more. Anyway, if the vehicle can’t lift 45-50 MT then I don’t think it is good to the military either because doesn’t the military want the capability to lift heavier satellites?

GCNRevenger · 2005-03-17 12:31:37

The big difference between Moon and Mars is primarily that it takes much longer to get there. To get to the Moon, stuffing the crew in a capsule the size of your bathroom for a few days isn't an issue, but for a six-month coast to Mars, you would obviously need more room, coming and going. You would also need much more in the way of supplies, life support, and radiation shielding.

Going to Mars 40MT at a time is a much poorer deal then the Moon because of this mass involved. Bob Zubrin's mission plan is much too optimistic to begin with about how much mass (~120MT capacity) is needed for a Mars payload. NASA starts with a much more reasonable 160MT as minimum baseline, but 200MT should be the target mass. No reasonably expensive clean-sheet rocket can do 200MT in a single throw, so dividing it up into two pieces and putting them on 80-100MT launchers is what we ought to do.

If we are talking 160-200MT for a single Mars payload, of which you would need three per expedition, then 40MT EELVs don't make much sense since you would need too many. No less then 13 EELV launches for NASA DRM. In this case, since you could probobly not launch all the liquid hydrogen in a single flight, boiloff would be a big problem. A big change from three or four for a Lunar expedition.

There is also the problem that the fuel tanks, HAB modules, aerobrake sheids, and so on will themselves be too big to fit on an enlarged 6.5m EELV faring.

A 40MT class Delta-IV is not an HLLV

John Creighton · 2005-03-17 13:15:20

If we are talking 160-200MT for a single Mars payload, of which you would need three per expedition, then 40MT EELVs don't make much sense since you would need too many. No less then 13 EELV launches for NASA DRM. In this case, since you could probobly not launch all the liquid hydrogen in a single flight, boiloff would be a big problem. A big change from three or four for a Lunar expedition.
There is also the problem that the fuel tanks, HAB modules, aerobrake sheids, and so on will themselves be too big to fit on an enlarged 6.5m EELV faring.
A 40MT class Delta-IV is not an HLLV

How much more dense is slush hydrogen? Could one tank of slush hydrogen be enough oxidize for two tanks of oxygen? Also forgive my mass but to get the 160 tons you say is the minimum that is 4 EELV per flight. Can one flight carry enough slush hydrogen for all the launches? Granted you need more then one flight for a mission but it doesn’t matter if you need twice as many EELV if you can produce them twice as fast for half the cost. What advance in manufacturing possible to cheapen EELV and speed up the production? Finally if an EELV can lift 40-50 MT without slush hydrogen how much more can it lift with hydrogen. Perhaps 40-50 MT is not the limit for a 3 core EELV. I am also interested in who big a satellite does the military want to lift. Might they be interested in lifting an 80 MT satellite? If so perhaps SDV makes more sence.

GCNRevenger · 2005-03-17 13:42:42

For the full-sized NASA DRM mission, they are assuming the use of nuclear NTR engines to keep the mass down to a more reasonable figure. The low-end 160MT sortie would require 57MT of fuel. The TMI stage weighs about 25MT empty (28MT with radiation shield for crew)... Assuming that the fuel tank itself weighs around 10MT, you are looking at ~80MT of payload to launch all the LH2 needed for the low-end (including extra tank penalty). 100MT easy for the high end mission.

EELVs can only be sortied about once per month, certainly no faster then three weeks. So, it isn't possible to launch two fuel flights before the first experiences unacceptable boiloff. To say nothing of launching the crew last to minimize their time in zero-G and radiation.

Slush Hydrogen is considerably more dense, but it wouldn't change the amount of hydrogen you need by mass much at all. It wouldn't reduce the tank mass buy by a few tonnes, and hence no likly reduce the total amount of fuel you need very much either.

As far as modifying the tripple-barrel Delta to carry more then 40MT or so, I think that is wishful thinking. The 40MT figure already takes into account more dense hydrogen fuel, addition of an SRM package, enhanced RS-68 and ML-60 engines, and light-weight Lithium fuel tanks. The amount of mass you can put into orbit with a volume of fuel is fixed, and our engines are reaching the practical limits of efficency (already topping 85%). So, to increase payload, you have to reduce the empty mass of the rocket by an equal amount. You can't keep doing this forever, even if your rocket had zero mass at all you would have limited payload.

Modifying the Delta-IV HLV to carry more then 40MT is probobly a non-starter, it might hit 50MT with the fancy cross-feed system and brand new first stage engines, but that is pushing it. The Atlas-V HLV probobly cannot be pushed any higher then this either, as it doesn't launch much more then Delta-IV HLV can.

For Mars, HLLV is a must.

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#51 2005-03-16 10:53:17

Re: Griffin nominated for NASA post - SpaceRef link to testimony

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Re: Griffin nominated for NASA post - SpaceRef link to testimony

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