Man Rating Atlas V or Delta IV?

[JimMcDade]

The carryover of the Space Shuttle SRBs in the Ares designs seems to bother some people. I don't know why some people insist that liquid propulsion engines are superior to solids for getting off the launch pad.

NASA is saving a lot of time, money, and jobs, by using the proven SRB components. SRBs are extremely simple in comparison to liquid engines, a feature which greatly enhances reliability.

You can't throttle or shutdown a solid, but that is about the only disadvantage unless you spring a plasma leak at one of the segment joints as happened with Challenger. A leak such as that could cause an abort for an Ares I launch, but the post-Challenger accident redesign appears to have eliminated that problem. The Ares I SRB will not have an ET mounted beside it, so it is unlikely that such an event would be fatal for a crew.

NASA is wisely to taking advantage of the best transferable Space Transportation System components for the next-generation of Space Vehicles. I can recall Buzz Aldrin proposing an Atlas-based Space Shuttle replacement system about ten years ago.

Here is an interesting blog post from WIRED commentator Loretta Hidalgo Whitesides.

http://blog.wired.com/wiredscience/2...sa-isnt-t.html

Some commenters have raised a very reasonable question: Why doesn't NASA just human rate an expendable launch vehicle like the Atlas V or the Delta IV? It seems reasonable because they fly all the time, they are big, they are reliable and they are already built. So what is the problem?


Weight- The Orion Crew Exploration Vehicle is too heavy for the Atlas V and the Delta IV (I will deal with other capsules after the jump). You also have to account for other mission constraints. For example, you have to include the loss of performance you get from going to the high inclination orbit of the International Space Station. ISS doesn't just fly directly over the equator but at an angle that allows it to pass over Russia. That orbit takes more energy to get to. In addition you will also lose performance because you have to fly a less aggressive launch profile. The current profile subjects payloads to 6 G's (Space Shuttle is 3 G's). Human payloads don't respond well to sustained 6 G loads. Flying a less aggressive profile will mean you will be able to lift less.


So all in all, you would need to develop a "triple-core" (three Atlas' strapped together) to be able to lift Orion. A triple core Atlas has never been flown. You would also need a new upper stage for an extra bit of kick at the end of the flight. The Delta IV, although larger and more mature, would also need a new upper stage.


Triple Redundancy- All human-rated vehicles are designed to be triply redundant. If something fails, there has to be two other options for the crew. It's like when the power goes out at your house, you have a back-up system which is a flashlight. If the flashlight fails, you have a second back up system which is a bunch of candles and matches. Now, to be stuck in the dark you would need to have all three systems fail. Cargo rockets are not designed with that much redundancy in their systems. Adding in that kind of redundancy after the fact would be like getting under the hood of your car and installing a back-up set of brakes. You have to create feed throughs for the wires, try to figure out where you will put the extra brakes etc.


Now to be fair, you could launch a smaller human vehicle on a current expendable rocket...(Orion does seat six).


In fact, before the Columbia disaster NASA teams were working on an Orbital Space Plane (OSP) designed to do just that. At the time, OSP was maligned for being small and limited in capability. (It is ironic that the Orion is now being maligned for being too large and capable.) OSP was a smaller vehicle designed to launch on an Atlas V or a Delta IV and seat "no less than four" crew members. It was eventually overcome by events when Constellation and the Moon, Mars, and beyond program kicked off and NASA transferred the knowledge gained on the OSP to the development of Crew Exploration Vehicle.


Then there is Robert Bigelow, a self made millionaire, who is building an inflatable space hotel (they already have a scale model on orbit now). He is converging on a deal with Lockheed Martin to human-rate a version of the Atlas V. This is plausible, given that they are looking for an OSP-class capability. Bigelow's main interest is getting clients to and from his future orbiting facilities.


SpaceX is also building a small capsule that could launch people to ISS or Bigelow's space hotel. Their Dragon capsule, being built to take cargo to the International Space Station, will fit on their Falcon 9 rocket and be able to launch humans. Although it will not fly on an Atlas or a Delta, it is in that same class of vehicles.


Perhaps in the end it is a good idea for NASA to focus their efforts on building the new, heavier Orion capsule and the Ares I and V. These vehicles are suitable for the longer, more demanding trips to the moon. Then NASA could leave the lighter, smaller low Earth orbit capsules to commercial space to work out. That would serve both the goal of NASA being an exploration agency and of evolving our commercial space sector.
So the short answer is: NASA is not human-rating an Atlas V because that system will not be sufficient for exploration beyond low Earth orbit (though Bigelow Aerospace is looking at human-rating the Atlas V).

[J.McDonald]

Hi Jim, interesting post.

Triple Redundancy- All human-rated vehicles are designed to be triply redundant

surely this must have its limits! I'm no rocket scientist, but how does, e.g., the shuttle's TPS fair in a 'triple redundancy' analysis? There must be other critical areas too, perhaps in the first two minutes of ascent when there is no abort option.
Thanks

John

[JimMcDade]

Hi Jim, interesting post.

surely this must have its limits! I'm no rocket scientist, but how does, e.g., the shuttle's TPS fair in a 'triple redundancy' analysis? There must be other critical areas too, perhaps in the first two minutes of ascent when there is no abort option.
Thanks

John

John, There are some people who claim that the Apollo Saturn V Launch Escape System could not have saved the astronauts if it had never been needed. The emergency parachute that was crammed inside Freedom 7 was also widely considered to be useless. For that matter, the entire Apollo lunar biological isolation was probably a waste of many millions of dollars. When the Navy divers opened the Apollo hatch and tossed in the BIGs, sea-spray and raw moon dust were liberally mixed.

Triple-redundancy and emergency procedures are, in reality, sometimes little more than a nice gesture. Spaceflight is a dangerous profession.

This is not directly related, but the early version of the USAF F-104 fighter jet utilized a downward-firing ejection seat design that killed a total of 21 pilots when the 104 experienced low-altitude failures. Ironically , that downward-firing was intended to save pilots from being killed by the big tail of the 104 when ejecting at supersonic speed. As you know, many aircraft incidents occur at low altitude during either takeoff or landing. The 104 had a pretty high stall speed and it could be a bear to land for the newer pilots. The 104 also had a fairly short range (730 miles) without the drop tanks and you did not want to run out of gas and have to make a dead-stick landing. The downward firing seats were quickly abandoned after so many pilots were fired directly into the ground.

[J.McDonald]

John, There are some people who claim that the Apollo Saturn V Launch Escape System could not have saved the astronauts if it had never been needed. The emergency parachute that was crammed inside Freedom 7 was also widely considered to be useless. For that matter, the entire Apollo lunar biological isolation was probably a waste of many millions of dollars. When the Navy divers opened the Apollo hatch and tossed in the BIGs, sea-spray and raw moon dust were liberally mixed.

Triple-redundancy and emergency procedures are, in reality, sometimes little more than a nice gesture. Spaceflight is a dangerous profession.

This is not directly related, but the early version of the USAF F-104 fighter jet utilized a downward-firing ejection seat design that killed a total of 21 pilots when the 104 experienced low-altitude failures. Ironically , that downward-firing was intended to save pilots from being killed by the big tail of the 104 when ejecting at supersonic speed. As you know, many aircraft incidents occur at low altitude during either takeoff or landing. The 104 had a pretty high stall speed and it could be a bear to land for the newer pilots. The 104 also had a fairly short range (730 miles) without the drop tanks and you did not want to run out of gas and have to make a dead-stick landing. The downward firing seats were quickly abandoned after so many pilots were fired directly into the ground.

I'm not sure where you're going with this.
On the one hand, you appear to agree with the statement that triple redundancy is required for any manned vehicle. Yet on the other hand you are happy to accept that many 'safety' system used in the past have been virtually worthless. Your description of some of these systems is frightening- surely it would make more sense to use the mass/funding wasted on these systems to shore up the weak points of the design.

I presume that I was correct in identifying that the shutle TPS is a single-point failure risk?

I do find the EELV argument a strong one. Danny Deger has written some interesting comments refuting the supposed 'black zones' for EELV aborts.

Perhaps I've spent too long over at NSF, but I can see how a 5-seg SRB plus a new US is a completely new vehicle. NASA reckon it's got excellent reliability, but they've not flown one yet. Apparently the shuttle was supposed to have a failure rate of 1:10,000! Look how wrong they were with that one.
The SRB cannot be terminated- what are the impacts of this on the LES? Must it be much more powerful to lift Orion cleanly away from the still-thrustin booster?

In any case, given that Ares-I is supposed to be the first step on the journey to the moon, I'm surprised that NASA is so worried about its reliability. There are plenty of other phases of the mission where the crew are in danger, and a chain is only as strong as its weakest link. If they have LOC/LOM numbers for Ares launch, presumably they have them for all phases of the lunar mission- can these be accessed anywhere?

The main advantage of the EELV, to me (other than schedule/cost concerns) is that it is already flying. We know how reliable they are, from actual flights, not from calculations. We entrust them with billion dollar national security payloads. And they would certainly be safer than the shuttle, or perhaps any previous NASA manned space vehicle.

[J.McDonald]

Three fault tolerance.... is a hoax! I quote: "The space system shall provide failure tolerance to catastrophic events (minimum of one failure tolerant)"


from http://nodis.gsfc.nasa.gov/displayDi...PR&c=8705&s=2B para 3.2.2

[Me2]

1. NASA is saving a lot of time, money, and jobs, by using the proven SRB components. SRBs are extremely simple in comparison to liquid engines, a feature which greatly enhances reliability. .

2. Weight- The Orion Crew Exploration Vehicle is too heavy for the Atlas V and the Delta IV (I will deal with other capsules after the jump).

3. So all in all, you would need to develop a "triple-core" (three Atlas' strapped together) to be able to lift Orion. A triple core Atlas has never been flown. You would also need a new upper stage for an extra bit of kick at the end of the flight. The Delta IV, although larger and more mature, would also need a new upper stage.


4. Triple Redundancy- All human-rated vehicles are designed to be triply redundant. If something fails, there has to be two other options for the crew. .

5. Now to be fair, you could launch a smaller human vehicle on a current expendable rocket...(Orion does seat six).


6. In fact, before the Columbia disaster NASA teams were working on an Orbital Space Plane (OSP) designed to do just that. At the time, OSP was maligned for being small and limited in capability. (It is ironic that the Orion is now being maligned for being too large and capable.) OSP was a smaller vehicle designed to launch on an Atlas V or a Delta IV and seat "no less than four" crew members.


7. So the short answer is: NASA is not human-rating an Atlas V because that system will not be sufficient for exploration beyond low Earth orbit .

I am going to throw the BS card and refute everyone of your bogus claims.

1. Wrong and wrong. The stick is no longer safe, simple and soon. The bad decision to select the stick has delayed the first flight by 2 years. Due to all the changes, the 5 segment is no longer the same as the 4 segment. The only thing that is common is the casings themselves and NASA might even change that by going to composites. The argument that the 1st stage booster is safe no longer applicable. The Stick SRB was to be only safe when they have large amounts of flight experience which doesn't apply any more

2. Orion is too heavy for Ares I also. The ISS crew has been cut from 6 to 4. What is good for the goose is good for the gander, NASA can adjust Orion requirements so that EELV's can fly it.

3. The triple core Atlas has already been designed. It went all the way to CDR. It could be ready in less than 30 months. Also, the Delta-IV is going to have an engine upgrade that will make it more powerful than the Stick. New upperstages are not needed, the vehicles can be used as is. Also there is a version of the Atlas V called Phase 2, which would have a wider core, elminiating the need for the strap on cores. This could be a very good CLV. Any of the EELV's options would cost less than 2 billion to field which would include pad mods for crew access.

4, Wrong. Ares I never could meet this requirement and the requirement was actually relaxed to allow the Stick to be used
NPR 8705 "http://nodis.gsfc.nasa.gov/displayDi...PR&c=8705&s=2B

5. wrong, the requirement for 6 has be changed to 4.

6. And the EELV's were fine for a crew at that time, so what changed that they are good enough for Orion.

7. Wrong. Orion only needs to get to LEO. The orion launch vehicle (stick or what ever) has nothing to done with the other mission. That is for Ares 5 or what ever.

The stick performance and redundancy card can't be used against EELV's since the stick can't meet the requirements either

[JimMcDade]

I am going to throw the BS card and refute everyone of your bogus claims.

1. Wrong and wrong. The stick is no longer safe, simple and soon. The bad decision to select the stick has delayed the first flight by 2 years. Due to all the changes, the 5 segment is no longer the same as the 4 segment. The only thing that is common is the casings themselves and NASA might even change that by going to composites. The argument that the 1st stage booster is safe no longer applicable. The Stick SRB was to be only safe when they have large amounts of flight experience which doesn't apply any more

Jim says: You are clearly begging the question by assuming that any or all of these changes to the "stick" are BAD. You cannot know that these changes are bad because you don't have access to the engineering process flow that preceded the announcement of these changes. Your statement that, "The Stick SRB was to be only safe when they have large amounts of flight experience", is presumptuous, at the very least.

2. Orion is too heavy for Ares I also. The ISS crew has been cut from 6 to 4. What is good for the goose is good for the gander, NASA can adjust Orion requirements so that EELV's can fly it.

Jim says: Leaping to conclusions and the inability to tell good evidence from bad. All reports from Steve Cook and NASA management state that the "stick" is still well within margins. Perhaps the six crew plan was too ambitious, but so what? Does that mean Ares I is a bad design? The crew reduction decision is not good or relevant evidence for the primary DIRECT 2.0 hoax claim that Ares I will kill astronauts. All launch systems gain weight as they move from the drawing board to the launch pad. Stuff always gets either reduced or eliminated. They had to take the seats and the second docking port off of the Apollo LM. Did that make the LM a bad design? A crew of four still allows the USA to launch more astronauts per launch than any other nation.

3. The triple core Atlas has already been designed. It went all the way to CDR. It could be ready in less than 30 months. Also, the Delta-IV is going to have an engine upgrade that will make it more powerful than the Stick. New upperstages are not needed, the vehicles can be used as is. Also there is a version of the Atlas V called Phase 2, which would have a wider core, elminiating the need for the strap on cores. This could be a very good CLV. Any of the EELV's options would cost less than 2 billion to field which would include pad mods for crew access.

Jim says: The Atlas series is awesome. I love Atlas, but what you are dreaming about can't and won't happen. Man rating the triple-core Atlas is not so simple or cheap. You simply aint gonna see any new man-rated vehicle in 30 months.

4, Wrong. Ares I never could meet this requirement and the requirement was actually relaxed to allow the Stick to be used
NPR 8705 "http://nodis.gsfc.nasa.gov/displayDi...PR&c=8705&s=2B

5. wrong, the requirement for 6 has be changed to 4.

6. And the EELV's were fine for a crew at that time, so what changed that they are good enough for Orion.

7. Wrong. Orion only needs to get to LEO. The orion launch vehicle (stick or what ever) has nothing to done with the other mission. That is for Ares 5 or what ever.

The stick performance and redundancy card can't be used against EELV's since the stick can't meet the requirements either

Jim says: Good to see that you have all of the answers. Are you intersted in replacing Steve Cook or replacing Michael Griffin with yourself? In summary, all of the changes to Ares I and Ares V are the result of engineering studies, sophisticated modeling and actual testing. That is what the NASA/industry team is paid to do.

All of the objections coming from the DIRECT 2.0 crowd are based upon a lack of understanding of the process that has been faithfully pursued under very trying budget conditions. The DIRECT 2.0 PowerPoint presentation is backed by little more than raw, unstudied, opinion. The objections that you and your friends keep listing here and elsewhere have been addressed and yet you guys keep coming with your stock reponses and relentless naysaying.

After soliciting for engineers who have a problem with ARES I, I finally received a reply from a person who may actually be a qualified engineer who says that he has some problems with Ares I. He has agreed to have a calm dialogue with me after I confirm his credentials and experience. I am hoping that he has some substantial objections and numbers to share with me. It will be nice to hear some reasonable objections as opposed to the unfounded claims, insults and ostracism that the DIRECT 2.0 folks have tossed at me when I question their wildest claims in their classic hoax conspiracy style. I can be converted if verifiable facts are presented. The DIRECT 2.0 advocates are seeming stuck in some kind of a tail-chasing routine that leaves them with no way to gracefully exit the public stage. Sad.

[Me2]

J

1. All of the objections coming from the DIRECT 2.0 crowd are based upon a lack of understanding of the process that has been faithfully pursued under very trying budget conditions. The DIRECT 2.0 PowerPoint presentation is backed by little more than raw, unstudied, opinion.

2. The objections that you and your friends keep listing here and elsewhere have been addressed and

3. yet you guys keep coming with your stock reponses and relentless naysaying.

1. What does this have to do with Direct? This thread is about manrating EELV's. I have said nothing about nor made any reference to Direct here.

2. You have not address the objections with anything of substance.

3. Look in a mirror. You are the one with the stock responses. Any thing that goes against the Stick, you have to come back with the relentless cheerleading. You have nothing to base your beliefs except PR spin.

[Me2]

1. Jim says: You are clearly begging the question by assuming that any or all of these changes to the "stick" are BAD. You cannot know that these changes are bad because you don't have access to the engineering process flow that preceded the announcement of these changes.

2. Your statement that, "The Stick SRB was to be only safe when they have large amounts of flight experience", is presumptuous, at the very least.

3. Jim says: Leaping to conclusions and the inability to tell good evidence from bad. All reports from Steve Cook and NASA management state that the "stick" is still well within margins. Perhaps the six crew plan was too ambitious, but so what? Does that mean Ares I is a bad design?

4. The crew reduction decision is not good or relevant evidence for the primary DIRECT 2.0 hoax claim that Ares I will kill astronauts.

5. All launch systems gain weight as they move from the drawing board to the launch pad. Stuff always gets either reduced or eliminated. They had to take the seats and the second docking port off of the Apollo LM. Did that make the LM a bad design?

6. A crew of four still allows the USA to launch more astronauts per launch than any other nation.

7. Jim says: The Atlas series is awesome. I love Atlas, but what you are dreaming about can't and won't happen. Man rating the triple-core Atlas is not so simple or cheap.

8.You simply aint gonna see any new man-rated vehicle in 30 months.

1. They are bad by definition because the "change" means the current booster is no longer related to the shuttle SRB flight experience. How do you know I don't have access? I have access.

2. It is not presumptuousbut a fact. It is basic rocket science. SRM reliability is based on a large experience base which is obtain by many flights and static burns.

3. The Stick is NOT within margins if the payload has to be reduced. By your same argument against Direct, it doesn't "meet the requirements of the VSE" which is 6 crew to ISS. And yes, it does mean Ares I is a bad design. It doesn't meet the requirements

4. Who said it did?

5. Wrong and bad analogy. The stick could never do the mission. It was a bad choice in the first place. As for the LM, it could still carry the crew members that it was required to unlike the stick. There was no requirement for seats or a second docking port. The requirements were a method for restrainng the crew and the ability to see the CSM during docking, which were met by a "harness" in the crew suits and a window on the ceiling of the LM

6. So? What does that have to do with this topic

7. It is simple, the process is known, and it would be cheaper than the cost of the Ares I-X test.

8. Yes we will. It will be the Falcon 9, with an Atlas close by. It definitely won't be the Ares I. A. Its first launch is in 2012 and B. Ares I will be canceled

[J.McDonald]

Jim: it would appear that Loretta has effectively retracted her article; you may wish to reconsider citing it, to avoid embarrassment.

[JimMcDade]

I have noting to be embarrassed about. My preceding comments about Ares I remaining within all required margins still hold up. I passed on the WIRED blogger's story for the benefit of this discussion. Loretta's recent education about triple-redundancy and the other blogger's comment about Orion executing a "significant burn to just get to orbit" are neither here nor there when it comes to the overall flight-worthiness of Ares I.

BTW- The DIRECT 2.0 Level 2 expert that contacted me is unable to offer any numbers to support the key DIRECT 2.0 claims. (I will refer to the expert as he, although it could be a she.) I agreed to protect his identity.

He can't offer the supporting numbers due to the fact that the pertinent documents are not cleared for distribution outside of the NASA/contractor circle. It is not that he is not trying to dialog, it is a matter of legal constraints on that discussion. It is currently impossible to substantiate the DIRECT 2.0 claims due to this lack of verifiable, evidential documentation. This source may or may not be an expert in space vehicle development but since his his stated objections are not evidential in nature, so I still cannot switch over to the DIRECT 2.0 side. It is clear that he does not like either Michael Griffin or George Bush but he cannot give me the numbers that would support the key technical claims against Ares I:

1) Lack of lift performance
2) Column buckling
4) Thrust Oscillation
5) LOM and LOC probability numbers

The non-technical claims against Ares I round out the complete list of 8 DIRECT 2.0 allegations:

6) Cost (more than doubled in the past two years)
7) Long developmental time (slipped three years in the last two years)
8) Ares I is no longer; as simple as they first thought, is not as safe as they thought it would be, and will be no where as soon as they thought it would be.

Stay tuned for more details. There is much more to this story. Some fascinating details are coming soon.

[Me2]

Again, what does Direct have to do with this thread? It is about manrating the EELV's. Also what does Ares I short comings have to do with Direct, they are independent of Direct.

Anyways, claims, 6, 7 & 8 are self evident.
6 Cost. Ares I was suppose to be an 4 segment SRB with SSME. The 5 segment SRB and the J-2 are more expensive
7. Ares I was to be fielded in 2011 or so, now it is 2014/15
8. 6&7 knock off soon and simple. The need for TO mitigation eliminates "safe" (it is no different from the EEE's)

[JimMcDade]

Me2, This is the DIRECT 2.0 forum. Do you think that we should create an Atlas/Delta forum so that we don't get things mixed up?

As for 6, 7 & 8, those are more legitimate claims. Does cost growth in a federal program really surprise you? The USA does not cancel programs when they become more costly than expected. They just spend more money.

The safety claims about Ares I are possibly the result of two things: 1) a misunderstanding or misinterpretation of very conservative NASA project risk management approach at this stage in Ares I development. 2) A misunderstanding of how the NASA Risk assessment matrix is used. It is used to outline the criteria by which technical issues can be qualitatively and initially prioritized. The matrix score is a guidance tool, not an ax of finality. That matrix also takes into account that the Ares project is extremely risk averse. That aversion to risks translates into an extremely sensitive and conservative matrix scorecard.

This is what Griffin told SPACE NEWS about the perceived slips:

"I do want to comment when you say Constellation internal milestones have been slipping to the right. I do want to put that in context because I don't think that's been done yet. So I'd like you guys to listen up on this.


We maintained for several years — on purpose and at my direction — internal milestones for Constellation that were as early as could be credibly done. Some would have even questioned whether they even were credible. I maintained the earliest milestones that we could precisely because — and you guys were in these hearings — there was much consternation about the length of the gap between shuttle retirement and Ares and Orion deployment and many questions about how much money would be required to accelerate development of the new systems by so many months. We had questions like that at virtually every hearing and so in order to have the program appropriately positioned should the congress have decided to provide extra money to Constellation, I didn't want the issue to be moot."

[J.McDonald]

I don't think this topic should slip. It's unfortunate that it's in the Direct section, but there you go.

Anyway, given that
1) The EELVs can meet the performance and safety needs of the CLV sooner than Ares
2) Ares I and V have diminishing commonality (diverging SRB designs)

what are the justifications for continuing the Ares-I program?

(not trolling here... genuinely curious!)

[Me2]

what are the justifications for continuing the Ares-I program?

Inertia is not a justification. Ares I is not too far along. Anyways, like all NASA programs it is due for the standard redesign. See SSF vs ISS, Lunar direct vs LOR, etc

[Rick]

what are the justifications for continuing the Ares-I program?

(not trolling here... genuinely curious!)

John,
As I have mentioned in more than a few posts, and now evidence exists that over 200 contracts are being implemented, its too late.

The end game is pretty clear in my opinion.

[Rick]

Inertia is not a justification. Ares I is not too far along. Anyways, like all NASA programs it is due for the standard redesign. See SSF vs ISS, Lunar direct vs LOR, etc

So are you saying that the Ares I-X is not going to launch eary next year?

If that is the case, please provide us with documentation to substantiate that please.

[Me2]

So are you saying that the Ares I-X is not going to launch eary next year?

If that is the case, please provide us with documentation to substantiate that please.

Never said anything about Ares I-X date, only that Ares I is not to far along for change. 200 contracts doesn't mean squat. NASA and DOD have canceled larger programs

But since you brought it up, it is the world's largest model rocket and a great waste of taxpayer's money. It is nothing about PR show and is a marginal test at best and certainly not worth the more than 1/2 Billion dollars it will cost. For that price, one of the EELV's could be manrated or a dedicated manned launch pad launch pad for one of them could be built *.

* this is from the OSP program

[J.McDonald]

John,
As I have mentioned in more than a few posts, and now evidence exists that over 200 contracts are being implemented, its too late.

The end game is pretty clear in my opinion.

So the justification is that.... it was chosen. thus it is justified? Pretty self-fulfilling. If that's the case, will NASA develop it no matter whether it is tehcnically the best option or not?

I've watched the CLV design evolve through many changes. It started as a 4-seg wth SSME. The SRB has changed greatly, I hear rumours about non-recovery and new casings, new propellants, etc. The upper stage has also changed thanks to dropping the SSME. The TO problem is well publicised. Of course you wouldn't expect a deveopment to be smooth, but I'm starting to wonder would NASA ever give up on this rocket? Even if its cost, safety, and schedule all fell behind the alternative(s)?

[Rick]

So the justification is that.... it was chosen. thus it is justified? Pretty self-fulfilling. If that's the case, will NASA develop it no matter whether it is tehcnically the best option or not?

No, I never said that John. All I mentioned were facts. There is no proof that I have seen, other than Directs inability to release a study to disprove NASA's decisions. Be that as it may, I'd also like to see proof that NASA's decision to go with Ares is wrong, and its not technically the best option, other than a group of people who are burning yet to be built bridges with the space agency, who insist NASA is covering up facts, and the NASA management is near 'criminal'.

That's not my cup of tea, and evidentely I have more faith in NASA's engineers than those who oppose Ares and NASA itself.