Author Topic: Griffin speech - EELV would not work for Constellation  (Read 44565 times)

Offline vt_hokie

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RE: Griffin speech - EELV would not work for Constellation
« Reply #40 on: 01/23/2008 11:51 pm »
Quote
Norm Hartnett - 23/1/2008  2:57 PM

And to address your question, if it is not used for Mars there are still the NEOs, Mars' moons, and Venus.

Venus?!  Might be a little warm for the crew...  ;)

One non-technical reason I don't like the Ares I/Ares V approach is that it allows Congress to cancel the heavy lift portion that's needed for beyond-ISS missions while still preserving some basic spaceflight capability.  When was the last time NASA completed a program in its entirety with all planned enhancements?  Just take a look at ISS!  I think getting heavy lift launch vehicle capability up front is the only way to ensure it doesn't get cut when the inevitable delays and cost overruns occur.

Offline jongoff

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RE: Griffin speech - EELV would not work for Constellation
« Reply #41 on: 01/24/2008 12:17 am »
Vt_Hokie,
Quote
Venus?!  Might be a little warm for the crew...  ;)

At the cloud top level, it really isn't that bad.  We're talking ~1atm pressure, roughly tropical temperatures, and since the atmosphere is mostly CO2, breathable air is a buoyant gas at that altitude.  I've heard people seriously propose building cloud colonies on venus.  Basically you use the breathable air at 1atm as the lifting gas, and build the whole colony as an airtight vessel.  Since the pressure is identical on both sides of the wall, even if there was a leak, it would be *very* slow.  You have to make sure your exterior surface can handle sulfuric acid (which are in the clouds), but that's also doable.  All in all it's interesting, because it may be one of the easiest planetary environments to build for.  No vacuum or ultra-low pressure to deal with, moderate temperatures, ~0.8g, plenty of atmosphere outside for thermal control purposes, plenty of sunlight (even below the cloudtop level, the light level is comparable to earth)....and you're surrounded by Carbon, Oxygen, Hydrogen, Nitrogen, and Sulfur.

Alas, the only problem is I can't think of too many markets to justify such a cloud city (other than tourism and/or retirement villas....)

Quote
One non-technical reason I don't like the Ares I/Ares V approach is that it allows Congress to cancel the heavy lift portion that's needed for beyond-ISS missions while still preserving some basic spaceflight capability.  When was the last time NASA completed a program in its entirety with all planned enhancements?  Just take a look at ISS!  I think getting heavy lift launch vehicle capability up front is the only way to ensure it doesn't get cut when the inevitable delays and cost overruns occur.

The other way to guarantee that you have exo-LEO capabilities that aren't at the mercy of Congress is to create a transportation architecture based on commercial elements and propellant depots.  But I'm sure I'm starting to sound like Jonny-One-Note on that count.  Once you have a propellant depot up and running long enough to start getting commercial customers, Congress (and NASA) is no longer on the critical path to the outward exploration/exploitation/development of space....

To me, *that's* sustainable.

~Jon

Offline edkyle99

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RE: Griffin speech - EELV would not work for Constellation
« Reply #42 on: 01/24/2008 12:31 am »
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savuporo - 23/1/2008  4:17 PM

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jongoff - 23/1/2008  11:50 AM
For existing, very low launch rate vehicles (EELV, SDVs, etc), you might have a point, but I'd be careful with generalities like that.
Considering Dnepr vs EELV launch costs per pound, the point just does not work.

Oh, please.  Do I have to write out the obvious disclaimer every time?  The one that says "all other things being equal"?  As in comparing launch vehicles built in the same country, using the same currency, the same labor laws, the same safety rules, the same environmental regulations, etc.?  

NASA isn't going to use Russian-built launch vehicles to fly to Mars, or the Moon, or where ever, unless national policy changes.  If that happens, then we can sit down and compare Dnepr per pound versus Proton per pound, etc..

 - Ed Kyle


Offline landofgrey

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Re: Griffin speech - EELV would not work for Constellation
« Reply #43 on: 01/24/2008 12:59 am »
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Antares - 23/1/2008  1:46 PM

It's kinda funny that 2.5 years after ESAS, he's still having to sell the architecture.  By now, one would think it could stand on its own merits.

The speech was for the benefit of understanding for those who have questions, and I'm sure it was the last thing Griffin wanted to talk about... yet... again. Simply put, ESAS has already been sold to everyone who matters: Congress, industry and the majority of the public who care, which is why it is now essentially a matter of law. The opposition from a vocal minority of the public, scientists and engineers notwithstanding, the architecture has been "sold" and most people agree with the basic direction. I know that doesn't sit well with proponents of EELV-derived solutions or DIRECT, but some people also still don't accept that Ron Paul isn't going to get elected or realize they're in the 5% minority (backhanded analogy). Presonally, I just hope we don't get bit by the decisions that have been made.
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Quote
landofgrey - 24/1/2008  1:59 AM

Quote
Antares - 23/1/2008  1:46 PM

It's kinda funny that 2.5 years after ESAS, he's still having to sell the architecture.  By now, one would think it could stand on its own merits.

The speech was for the benefit of understanding for those who have questions, and I'm sure it was the last thing Griffin wanted to talk about... yet... again. Simply put, ESAS has already been sold to everyone who matters: Congress, industry and the majority of the public who care, which is why it is now essentially a matter of law. The opposition from a vocal minority of the public, scientists and engineers notwithstanding, the architecture has been "sold" and most people agree with the basic direction. I know that doesn't sit well with proponents of EELV-derived solutions or DIRECT, but some people also still don't accept that Ron Paul isn't going to get elected or realize they're in the 5% minority (backhanded analogy). Presonally, I just hope we don't get bit by the decisions that have been made.

Got to admit that's a great post.
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Offline Jim

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Re: Griffin speech - EELV would not work for Constellation
« Reply #45 on: 01/24/2008 01:11 am »
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landofgrey - 23/1/2008  8:59 PM
Simply put, ESAS has already been sold to everyone who matters: Congress, industry and the majority of the public who care, which is why it is now essentially a matter of law.

There is no law that says NASA must follow ESAS.   VSE is law

Offline yinzer

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Re: Griffin speech - EELV would not work for Constellation
« Reply #46 on: 01/24/2008 01:52 am »
Furthermore, the first few years of the ESAS are already sold to everyone who matters.  There are two more administrations and four more Congresses that will have to stay sold on the ESAS to get to the first manned Orion flight.  These are the people to whom the serious discussions about the real problems of ESAS are addressed.
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Offline CFE

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RE: Griffin speech - EELV would not work for Constellation
« Reply #47 on: 01/24/2008 02:11 am »
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edkyle99 - 23/1/2008  2:38 PM

Quote
Danny Dot - 23/1/2008  3:21 PM

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Chris Bergin - 23/1/2008  11:30 AM

http://www.nasa.gov/pdf/208916main_Space_Transportation_Association_22_Jan_08.pdf

Here's the part that will make many a coffee be spat over screens in Denver etc. ;)

snip

The Ares I lift requirement is 20.3 mT for the ISS mission and 23.3 mT for the lunar mission.  EELV lift capacity for both the Delta IV and Atlas V are insufficient, so a new RL-10 powered upper stage would be required, similar to the J-2X based upper stage for Ares I.  We considered using additional strap-on solid rocket boosters to increase EELV performance, but such clustering lowers overall reliability.

ship


What is the lift capability of Delta and Atlas heavy?  I am certain Atlas Heavy can lift this much and it is already at CDR with a very low risk to first flight.

Danny Deger

My recollection is that NASA's study showed that the EELVs couldn't lift the payload when restricted to the low-loft ascent profiles.  They would also carry a lot of LAS mass, etc., that would limit them compared to a typical satellite in a shroud type payload.  Together, these factors dramatically cut the EELV mass delivery capabilities for a CEV.  

 - Ed Kyle

Of course, the question must be asked why Orion weighs so much to begin with.  In my reading of the ESAS report, I have yet to find any rationale why the capsule is so huge for such a minuscule crew.  It begs the question of whether the capsule was deliberately designed to place it out of reach of the existing Delta family.

Delta IV Heavy is up to the task of launching a manned capsule, but it admittedly isn't the safest theoretical design out there.  On paper, Ares I is a much simpler, safer design.  But Delta IV Heavy has the edge in terms of actual flight experience.  Ares I has absolutely zero flight experience, and whatever heritage components are being used on Ares are being used in a flight environment that has little relevance to the one in which they were qualified (Shuttle & Saturn.)

So when Michael Griffin and co. boast about how safe Ares will be, tell them that you'll believe it when you see it.  An ounce of test is worth at least a pound of theory.
"Black Zones" never stopped NASA from flying the shuttle.

Offline jongoff

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RE: Griffin speech - EELV would not work for Constellation
« Reply #48 on: 01/24/2008 02:53 am »
Ed,
Quote
Oh, please.  Do I have to write out the obvious disclaimer every time?  The one that says "all other things being equal"?  As in comparing launch vehicles built in the same country, using the same currency, the same labor laws, the same safety rules, the same environmental regulations, etc.?  

NASA isn't going to use Russian-built launch vehicles to fly to Mars, or the Moon, or where ever, unless national policy changes.  If that happens, then we can sit down and compare Dnepr per pound versus Proton per pound, etc..

I agree that Dnepr is an unfair comparison.  That said, even with launchers built in the same country, using the same labor and safety rules, and the same environmental regulations, there still is plenty of other things which sometimes aren't equal.  The biggest one being the effect of flight rate.  It's possible that even though Jupiter is slightly smaller than Ares-V, that it may end up being cheaper in $/kg because it could fly more often, uses less engines, less segments, requires less R&D to be amortized, etc.

~Jon

Offline Antares

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RE: Griffin speech - EELV would not work for Constellation
« Reply #49 on: 01/24/2008 04:45 am »
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Tim S - 23/1/2008  2:39 PM
Well said Mr Griffin.

We're not talking about U-Haulers for cargo here. We're talking manned space flight.

EELV folks on here need to stick to what they know.
I hope you get up early and have Sen. Shelby on speed dial.  Some morning in the not too distant future when the sun rises over the Atlantic, the dawn will be cast on a winged vehicle atop an EELV pointed at Space.  Wisps of GOX will be venting from its haunches (no vent arm needed).  Ice will be forming and falling away in the humid air.  Turbopumps will spin and steam and maybe carbon dioxide will rush forth, without a hint of HCl or molten aluminum polluting the precious refuge.

An hour or so later, there will be much rejoicing in Denver, Florida, LA AFB, and the south side of the Tennessee River in Northern Alabama.  Those on the north side of the river will still be wondering why their square-tired Ferrari is still 5 years from launch and there's a Ford in space.  That night, all those Congressmen who don't usually care about Space will look skyward and have their own Sputnik moment as the "cargo" orbits past and realize there's a chance America may still be able to sell burgers on the moon before we have to put up with free samples of bourbon chicken.

We'll stick with what we know: fulfilling customer requirements, market-driven systems, true risk management, successful product development, cost-effective mission success.

Please, go do Ares V.  Just stop wasting time and money on another 50K-class launch vehicle when cheaper, adequate ones already exist.
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Offline khallow

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Re: Griffin speech - EELV would not work for Constellation
« Reply #50 on: 01/24/2008 05:09 am »
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landofgrey - 23/1/2008  5:59 PM

Quote
Antares - 23/1/2008  1:46 PM

It's kinda funny that 2.5 years after ESAS, he's still having to sell the architecture.  By now, one would think it could stand on its own merits.

The speech was for the benefit of understanding for those who have questions, and I'm sure it was the last thing Griffin wanted to talk about... yet... again. Simply put, ESAS has already been sold to everyone who matters: Congress, industry and the majority of the public who care, which is why it is now essentially a matter of law. The opposition from a vocal minority of the public, scientists and engineers notwithstanding, the architecture has been "sold" and most people agree with the basic direction. I know that doesn't sit well with proponents of EELV-derived solutions or DIRECT, but some people also still don't accept that Ron Paul isn't going to get elected or realize they're in the 5% minority (backhanded analogy). Presonally, I just hope we don't get bit by the decisions that have been made.

Another thing to keep in mind is that even if the architecture were absolutely perfect, it'd still be threatened by the "this money could be better spent elsewhere" crowd. Having said that, I don't think the Ares program is assured of survival. Not even Ares 1. This year will be a critical one for Ares.
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Offline kkattula2

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RE: Griffin speech - EELV would not work for Constellation
« Reply #51 on: 01/24/2008 06:12 am »
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A bigger launch vehicle is always going to cost less on a $/kg payload basis when it is compared to a smaller launch vehicle if the payload requirements are large enough or the program time frame is long enough, or both.  Ares V outhauls Direct, and so will always beat it at that cost-comparison game when it comes to Mars missions that start in 2030, require a million pounds of payload in LEO for each mission, and are part of a Mars exploration program that continues forever.

That might be true over 30 years, IF you only compare Ares V and Jupiter 232.

But if you throw in Ares I and Jupiter 120 for the LEO missions. Direct is a little ahead.

Then if you add in other jobs Juptiter 120 can do (ISS construction, large science payloads, etc), Direct is well ahead.

Then if you factor in the costs of; a big post shuttle gap, reduced safety margins in the CEV, workforce retention, impact on current budget, Direct is miles ahead.


Griffin is missing the big picture, even though he practically defines it. Nasa needs cheap, reliable, crew and heavy launch capability. Get that working, using your existing technology base, and then you can spend money on the more interesting things. Like exploration.

Offline renclod

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Re: Griffin speech - EELV would not work for Constellation
« Reply #52 on: 01/24/2008 06:35 am »
Quote
kevin-rf - 23/1/2008  9:42 PM

Noticed he said nothing about the five segment thrust oscillation issues

But he did. In the Q&A session that follows the speach.

The speach has a few twists on top of what you can read in the pdf.

Keith Cowing has recorded the whole session and has made it available for all to listen - thanks Keith !
See
http://www.spaceref.com/news/viewsr.html?pid=26756
http://onorbit.com/podcasts/2008.01.08.griffin.sta.m4a
feed://onorbit.com/podcasts/onorbitpodcasts.xml

 Enjoy !

Offline savuporo

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Re: Griffin speech - EELV would not work for Constellation
« Reply #53 on: 01/24/2008 07:03 am »
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Chris Bergin - 23/1/2008  4:01 PM

Quote
landofgrey - 24/1/2008  1:59 AM

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Antares - 23/1/2008  1:46 PM

It's kinda funny that 2.5 years after ESAS, he's still having to sell the architecture.  By now, one would think it could stand on its own merits.

The speech was for the benefit of understanding for those who have questions, and I'm sure it was the last thing Griffin wanted to talk about... yet... again. Simply put, ESAS has already been sold to everyone who matters: Congress, industry and the majority of the public who care, which is why it is now essentially a matter of law. The opposition from a vocal minority of the public, scientists and engineers notwithstanding, the architecture has been "sold" and most people agree with the basic direction. I know that doesn't sit well with proponents of EELV-derived solutions or DIRECT, but some people also still don't accept that Ron Paul isn't going to get elected or realize they're in the 5% minority (backhanded analogy). Presonally, I just hope we don't get bit by the decisions that have been made.

Got to admit that's a great post.

Except that it tries to paint a picture that really isnt there. Being "sold" doesnt mean eternal support from political institutions, and saying things like "vocal minority of engineers" and "most people agree" is just pulling stuff from thin air.
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Offline savuporo

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RE: Griffin speech - EELV would not work for Constellation
« Reply #54 on: 01/24/2008 07:17 am »
Quote
CFE - 23/1/2008  5:11 PM
Of course, the question must be asked why Orion weighs so much to begin with.  In my reading of the ESAS report, I have yet to find any rationale why the capsule is so huge for such a minuscule crew.  
If you read Griffins speech, you'll notice that even the crew size is a random number pulled out of .. air. The only justification is "its bigger than Apollo", which is a very weak argument to commit to billions worth of suspect hardware, without doing further tradeoff analysis.
What if it was three ? What if you landed two landers in close coordination, both carrying a crew of two, i.e. use lunar surface mission staging ?
Another big gotcha is the entire justification on going heavy lift: hydrogen boiloff, and "obviousness" of not wanting to stage 20-ton modules on LEO. I never understood how it became so obvious.
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Offline Jim

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RE: Griffin speech - EELV would not work for Constellation
« Reply #55 on: 01/24/2008 11:59 am »
Quote
Antares - 24/1/2008  12:45 AM

Quote
Tim S - 23/1/2008  2:39 PM
Well said Mr Griffin.

We're not talking about U-Haulers for cargo here. We're talking manned space flight.

EELV folks on here need to stick to what they know.
I hope you get up early and have Sen. Shelby on speed dial.  Some morning in the not too distant future when the sun rises over the Atlantic, the dawn will be cast on a winged vehicle atop an EELV pointed at Space.  Wisps of GOX will be venting from its haunches (no vent arm needed).  Ice will be forming and falling away in the humid air.  Turbopumps will spin and steam and maybe carbon dioxide will rush forth, without a hint of HCl or molten aluminum polluting the precious refuge.

An hour or so later, there will be much rejoicing in Denver, Florida, LA AFB, and the south side of the Tennessee River in Northern Alabama.  Those on the north side of the river will still be wondering why their square-tired Ferrari is still 5 years from launch and there's a Ford in space.  That night, all those Congressmen who don't usually care about Space will look skyward and have their own Sputnik moment as the "cargo" orbits past and realize there's a chance America may still be able to sell burgers on the moon before we have to put up with free samples of bourbon chicken.

We'll stick with what we know: fulfilling customer requirements, market-driven systems, true risk management, successful product development, cost-effective mission success.

Please, go do Ares V.  Just stop wasting time and money on another 50K-class launch vehicle when cheaper, adequate ones already exist.

And there is even irony.  MSFC couldn't handle the project and got it canceled.

Offline meiza

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Re: Griffin speech - EELV would not work for Constellation
« Reply #56 on: 01/24/2008 12:23 pm »
I think four crew is justified by enabling two EVA pairs. If you have three, it's dangerous if one goes alone and thus you have to move as a group of three and then it's not that much more useful than just two since you can't spread out much. So either 2 or 4.

I do realize that this is just a speech with limited time and Griffin can't just include every possible reasoning but some stuff still would warrant closer scrutiny.

I'm especially interested in the Delta IV heavy aborts and payload capability loss with a depressed trajectory. And the same thing for Atlas V heavy (18 months from Go to production).

Offline kevin-rf

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Re: Griffin speech - EELV would not work for Constellation
« Reply #57 on: 01/24/2008 01:18 pm »
Quote
meiza - 24/1/2008  8:23 AM

I think four crew is justified by enabling two EVA pairs. If you have three, it's dangerous if one goes alone and thus you have to move as a group of three and then it's not that much more useful than just two since you can't spread out much. So either 2 or 4.

A few points on that magic number.

First, on the moon and even in space you are limited to the crew on hand. There is no going for help. It doesn't matter if it is two, three, or four. You are limited to the muscle power of the others in the group. There are no solo space walks, most likely for that reason.

A few things to think about, (I do a fair amount of project caving and actually have a good amount of cave rescue training.)

In caving where you are realistically cut off from the rest of the world in a hostile enviroment the magic number is three. One to stay with the patient (we never use the word vicitim, to cavers thats means passed on to the underworld) and one to go for help. The first rule is to self rescue if you can, sending one ahead, and one to assist. Think about it, if you are eight hours from the surface, it will take at least 24 for assistance to arrive. That is why self rescue is so important. On the moon it can be measured in weeks or even months. Show me a moon suit that has a months air supply. It is also worth noting that multiple people injured during a cave accident is rare. It will most likely be the same during a lunar sortie.

The other thing to think about is cave diving. I have several friends that do it and do drag tanks when asked. In cave diving the magic number is almost always two (unless your a NE sump diver, then it is one (the thought of death wish comes to mind) ). It is an unforgiving enviroment, you almost never hear about non fatal cave diving accidents. When you reach a third of a tank consumed turn arround, keep an eye on the guy behind you, if you loose track of them stop and wait for them, assist them if they need help. This is very similar to space walks on the ISS, ever notice they are done in groups of two, even when the shuttle is docked.

During a surface sortie, the more the better to help out with any issue that might develop. Four is not the magic number, just a nice number since you now have three people to drag back an injured team mate. ( One to grab each arm, and another to take a video to post on YouTube ;) )
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Offline James Lowe1

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RE: Griffin speech - EELV would not work for Constellation
« Reply #58 on: 01/24/2008 03:58 pm »
Thread deleted back to before the arguments. Uh oh, too far back it seems :(


Offline clongton

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RE: Griffin speech - EELV would not work for Constellation
« Reply #59 on: 01/24/2008 04:16 pm »
Quote
James Lowe1 - 24/1/2008  11:58 AM

Thread deleted back to before the arguments. Uh oh, too far back it seems :(

Thank you very much.
This speech is a major event, and there is room here for an awful lot of evaluation and discussion of it. It’s unfortunate when it drops into such back and forth. New posters need to learn the proper use of PM’s for that stuff if they wish to pursue it and to keep it off the thread.
Thanks
P.S. I'm sure you'll fix it.  :)
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I started my career on the Saturn-V F-1A engine

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