Author Topic: DIRECT v2.0 - Thread 2  (Read 595802 times)

Offline Lancer525

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Re: DIRECT v2.0 - Thread 2
« Reply #3740 on: 12/31/2008 01:35 AM »
One other thing that has occurred to me, and if I'm wrong, Chuck, Ross, Mark or one of those guys who know all the science and numbers and what's going on can correct me.

Since Orion has been downsized for weight, removing some of those pesky old safety features, would it not then allow re-introduction of some, if not most, if not all of them if an LV were able to lift it? Is this not reason alone, crew safety (in light of the NASA report on Columbia released today) to implement a booster system that is really a *system* that follows the mandate of law to reuse as much STS infrastructure and engineering as possible?

Keeping all of those things in mind, why would the Obama Transition Team not want to check more deeply into a system that not only follows the law, and also can carry the safer Orion?

Why is this not mentioned more?

Its one of the things I pointed out in my letter to the NYT, but I have not, as yet, heard back from them.

I think that the grass-roots effort to promote DIRECT ought to restate the safety issues with Orion, the compliance with the law, the jobs saved and economic stimulus, and the much reduced gap that will be the result of this LV system.

"For some inexplicable reason, everyone seems to want to avoid simple schemes."   -John Houbolt

Offline Mark S

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Re: DIRECT v2.0 - Thread 2
« Reply #3741 on: 12/31/2008 03:38 AM »
One other thing that has occurred to me, and if I'm wrong, Chuck, Ross, Mark or one of those guys who know all the science and numbers and what's going on can correct me.

Since Orion has been downsized for weight, removing some of those pesky old safety features, would it not then allow re-introduction of some, if not most, if not all of them if an LV were able to lift it? Is this not reason alone, crew safety (in light of the NASA report on Columbia released today) to implement a booster system that is really a *system* that follows the mandate of law to reuse as much STS infrastructure and engineering as possible?

Keeping all of those things in mind, why would the Obama Transition Team not want to check more deeply into a system that not only follows the law, and also can carry the safer Orion?

Why is this not mentioned more?

Its one of the things I pointed out in my letter to the NYT, but I have not, as yet, heard back from them.

I think that the grass-roots effort to promote DIRECT ought to restate the safety issues with Orion, the compliance with the law, the jobs saved and economic stimulus, and the much reduced gap that will be the result of this LV system.



Lancer,

    Thanks for including me (I think) in with the smart guys, but I'm just a space fan in general and DIRECT fan in particular.  I take that as a great compliment, but I'm not associated with DIRECT at all.  Just to be clear.

    I strongly agree that we need to find a way to leverage all aspects of the DIRECT proposal both for better public awareness and industry acceptance.  I know that Ross and Chuck have gone to extremes to avoid antagonizing anyone, and they are much better at sticking to facts, logic, and reason than I am.  I tend to get wrapped up in the heat of the moment.

    The problem with asserting that DIRECT complies more closely to the NASA Authorization Act of 2005 than Ares is that no one in power seems to care.  Yes, the law was written in one particular and explicit way, but they are leaving it up to the Rocket Scientist In Charge on how best to implement their law.  Of course what they see as a discretionary variation, we see as a blatant bait and switch routine.  You and I know that there is no way any objective person could compare Ares and Jupiter and conclude that Ares is a closer derivative of STS than Jupiter.  But they just do not care.

    The powers that be also give the incumbent administrator the benefit of the doubt in controversial situations.  That is understandable up to a point.  But when there are so many voices raising serious concerns about the current direction; when people are afraid to speak out for fear of getting fired; and when the recent history of NASA is "Management Ignoring and Overriding their Engineers when it Matters the Most"; I think we should be able to convince a new Administration that an objective evaluation of all current options, including EELV, DIRECT, and ARES (at the least), would be a prudent and wise decision.

    The two points of yours that those in power will at least pay lip service to are safety and budget concerns.  I believe that DIRECT has the advantage over ARES in both areas, for all the reasons that the DIRECT team has enumerated.  The trick is to get their attention by letting them know that their decisions and lack of oversight are putting our astronauts, and the space program as a whole, at risk.  I don't know how to do that without sounding alarmist or antagonistic.  But it needs to happen.  I don't think they will be moved by any other considerations.

Mark S.

Offline Mark S

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Re: DIRECT v2.0 - Thread 2
« Reply #3742 on: 12/31/2008 06:32 PM »
Wow, this thread has been really quiet this week.  I guess everyone is just waiting for the days to pass....

Meanwhile, elsewhere on the Interwebs, I continue my thankless task of promoting DIRECT when possible.  Yesterday, Slashdot had a discussion on the recent NYT "NASA Fight Club" article.  Someone (not me) posted a pro-DIRECT reference, who was then accused of drinking DIRECT "cool-aid".  So I put my two cents in right here.

So, if anyone has time to review my effort and give me feedback I would appreciate it.  I know most of you here are hard core space techies, but I was trying to be informative and persuasive without alienating the general audience.

So would you say I sounded:

1) informative? 
2) persuasive? 
3) relatively accurate? 
4) too shrill? 
5) tin-foil hatter? 
6) correct level of detail? 
7) anything else?

Thanks

Offline clongton

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Re: DIRECT v2.0 - Thread 2
« Reply #3743 on: 12/31/2008 06:38 PM »
Wow, this thread has been really quiet this week.  I guess everyone is just waiting for the days to pass....

Meanwhile, elsewhere on the Interwebs, I continue my thankless task of promoting DIRECT when possible.  Yesterday, Slashdot had a discussion on the recent NYT "NASA Fight Club" article.  Someone (not me) posted a pro-DIRECT reference, who was then accused of drinking DIRECT "cool-aid".  So I put my two cents in right here.

So, if anyone has time to review my effort and give me feedback I would appreciate it.  I know most of you here are hard core space techies, but I was trying to be informative and persuasive without alienating the general audience.

So would you say I sounded:

1) informative? 
2) persuasive? 
3) relatively accurate? 
4) too shrill? 
5) tin-foil hatter? 
6) correct level of detail? 
7) anything else?

Thanks


Mark
I think it was just right.
Thanks
Chuck
You don't get to come back and try it later, so suck it up and get on the rocket.

Offline Mark S

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Re: DIRECT v2.0 - Thread 2
« Reply #3744 on: 12/31/2008 07:22 PM »

Mark
I think it was just right.
Thanks


Thanks Chuck!  That means a lot, coming from a DIRECT team member.


Offline Khadgars

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Re: DIRECT v2.0 - Thread 2
« Reply #3745 on: 12/31/2008 08:26 PM »
Quote
Mark
I think it was just right.
Thanks

You know I'm a Direct convert, looking at the two designs now I don't see how you couldn't go with Direct.

How ever a lot of time has passed since that decision had to be made and one thing I do agree with Dr. Griffin is that you can't keep stopping every year and try to redesign the rocket or you'll end up with nothing.  That to me is my biggest fear.

Second the whole idea that Direct is safer is misplaced imho, as Direct refers to safer in regards to the Orion capsule.  Orion will never fly if it's unsafe and Ares 1 was chosen because it was the safest launch vehicle they could produce which is something  I think needs to be recognized. 

Third how realistic is the Direct time table?  If I was presented with the choices of Direct or Ares come Jan 20th I would be skeptical that Direct would be able to live up to it's promise.  I've read the time lines presented and they seem to be very generous.  I could be wrong or this information could already be ready for people more important than I but perhaps highlighting how Directs major technical hurdles will be over come and how are they much different that Ares (in regards to how Ares 1 problems can't be over come but Direct can be), every rocket has it's hurdles right?

Finally how well can all the restructuring of the contracts go?  That's got to be a major concern since you're going to be asking out side sources to stop building what NASA told them to, and build a whole new design.  How much money and time will be lost there?  What happens if one of the contractors doesn't want to go along?  We could end up with a big cow pie if things turn south.

Those are just a few concerns that come to mind from some one not inside NASA and don't feel the need to respond as I don't want to waste your time as I'm sure you're busy.  I'm just expressing my internal conflict   :o


Offline clongton

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Re: DIRECT v2.0 - Thread 2
« Reply #3746 on: 12/31/2008 09:08 PM »
 
  You know I'm a Direct convert, looking at the two designs now I don't see how you couldn't go with Direct.
  An awful lot of people agree with you.
 
 
Quote
How ever a lot of time has passed since that decision had to be made and one thing I do agree with Dr. Griffin is that you can't keep stopping every year and try to redesign the rocket or you'll end up with nothing.  That to me is my biggest fear.
  Dr Griffin is right in that once a decision is made, you press forward with it. Otherwise nothing gets done. However, if you study the history of how NASA projects are run, there are decision points all along the way that must get a pass or the program is either terminated or replaced. Throughout all of NASA's history this has been followed, and many a NASA project has been cut because at these decision points they couldn't pass the grade. This time is different however. There have been several points in this program where Ares-I couldn't pass the decision node. But instead of doing the right thing and changing the program, the decision standards were actually lowered to the point that the LV passed. NASA then happily announced to the world that the Ares project has passed yet another milestone. I don't think it's a stretch to call this hypocrisy. This has led many to believe, rightly or wrongly, that Dr Griffin's goal was not to implement the VSE, but to build and fly the Ares rocket which he designed before he was the Administrator, back in his Planetary society days. The clamor to change the program is a cry from people who know what's happening on the inside to return to a sane launch vehicle program so that we can get on with the VSE. What the fear is, and it is very real, is that when Ares goes down as many believe it will, it will take the entire VSE, and possibly the American manned spaceflight program, with it.
 
 
Quote
Second the whole idea that Direct is safer is misplaced imho, as Direct refers to safer in regards to the Orion capsule.  Orion will never fly if it's unsafe and Ares 1 was chosen because it was the safest launch vehicle they could produce which is something  I think needs to be recognized.
  No, DIRECT refers to safer in terms of the launch vehicle. By every measure that matters, the Jupiter-120 is a safer launch vehicle than the Ares-I. For example it doesn't have to execute an engine start at high altitude - there is no extra staging event as there is on Ares-I. Also, the Jupiter-120 uses two main engines and can actually experience an engine out event at 45 seconds after launch and still achieve orbit. Such an experience on the Ares would trigger an immediate abort. The Jupiter-120 uses the 4-segment SRB that NASA has been flying for 30 years and has literally tons of heritage data on. We know how that system works, while the Ares-I uses a totally new SRB with no history and no heritage. It only "looks" like the old SRB. There are many other examples, but the bottom line is that the Jupiter-120 "launch vehicle" is safer than the Ares-I "launch vehicle".
 
 
Quote
Third how realistic is the Direct time table?  If I was presented with the choices of Direct or Ares come Jan 20th I would be skeptical that Direct would be able to live up to it's promise.  I've read the time lines presented and they seem to be very generous.  I could be wrong or this information could already be ready for people more important than I but perhaps highlighting how Directs major technical hurdles will be over come and how are they much different that Ares (in regards to how Ares 1 problems can't be over come but Direct can be), every rocket has it's hurdles right?
  Yes, every rocket has its hurdles. But the timelines we have presented have been put together by the people at MSFC who do the scheduling of projects. It's NASA personnel that are saying we can do this. We are only relaying their conclusions. They give us the data and we make the presentation graphs. The schedule we have presented is actually not aggressive at all. Remember, we really don't loose any significant time by switching to DIRECT because most of what has been done for Ares-I has direct application to the Jupiter-120. In addition, the Jupiter is based solidly on the NLS which, unlike the Ares-I, actually got well past the point of a REAL PDR before the Congress dropped funding because of fiscal conflicts.
 
 
Quote
Finally how well can all the restructuring of the contracts go?  That's got to be a major concern since you're going to be asking out side sources to stop building what NASA told them to, and build a whole new design.  How much money and time will be lost there?  What happens if one of the contractors doesn't want to go along?  We could end up with a big cow pie if things turn south.
  The contract proposals we have put on the table reflect what all the current Ares contract holders have said makes sense to them and they would be willing to do. Remember, these are only "proposals", and reflect the thinking of the current Ares contractors, not just us. But they make good sense and give all the current players an approximately equal share as they get with the contracts that are in place now. But the proposals are not "pie in the sky". They are based on what the current players have told us is workable. The current contract holders have told us that they believe what we have presented, with their participation, is easily doable. Having said all that, the legal aspects of the contract changes are not within our range of expertise and will need to be properly negotiated and executed by the parties involved.
 
 
Quote
Those are just a few concerns that come to mind from some one not inside NASA and don't feel the need to respond as I don't want to waste your time as I'm sure you're busy.  I'm just expressing my internal conflict.
  Responding to genuine questions is not a bother to us. It's actually something we like to do. Sometimes it's me, sometimes it's Ross, and sometimes it's other members of the team using their Forum names.  But never stop asking. Please continue to bring your concerns up and we will address them as best as we can.
 
  Thank you for taking the time to formulate and ask your questions.
 
  Regards
« Last Edit: 12/31/2008 09:37 PM by clongton »
Chuck
You don't get to come back and try it later, so suck it up and get on the rocket.

Offline Bill White

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Re: DIRECT v2.0 - Thread 2
« Reply #3747 on: 12/31/2008 09:16 PM »
I continue to believe one of the strong political arguments for Direct arises from the ample throw weight margins of J-120 versus either EELV or Ares 1.

The ability to simply add 1000 kg to the spacecraft (for example) to solve an unexpected problem rather than engineer the be-jeebers out of it would seem highly beneficial to both shortening "the Gap" and getting the Orion design completed at a lower cost.
EML architectures should be seen as ratchet opportunities

Offline Khadgars

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Re: DIRECT v2.0 - Thread 2
« Reply #3748 on: 12/31/2008 09:53 PM »
Quote
The clamor to change the program is a cry from people who know what's happening on the inside to return to a sane launch vehicle program so that we can get on with the VSE. What the fear is, and it is very real, is that when Ares goes down as many believe it will, it will take the entire VSE, and possibly the American manned spaceflight program, with it.

Yes that is my biggest fear, one in which I'm willing to see Ares go forward in order to preserve.  As much as Direct is better over Ares, Ares is better than nothing and is quite capable of fulfilling VSE. 

And odd question but if Direct is shot down in the coming months (which I hope it's not) would the Direct team be willing to swallow the bullet and press ahead and try to make Ares as successful as possible in order to preserve American spaceflight?
 
Quote
  Yes, every rocket has its hurdles. But the timelines we have presented have been put together by the people at MSFC who do the scheduling of projects. It's NASA personnel that are saying we can do this. We are only relaying their conclusions.

Very reassuring, that's got to be a major strong point for the Direct case when presenting it to the powers that be.  Would Direct be willing to keep Dr. Griffin on board if he was willing in order to prevent a major political shake up with in the agency?  Stability will be key in seeing the program move forward with VSE.
 
« Last Edit: 01/01/2009 12:48 AM by Khadgars »

Offline Will

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Re: DIRECT v2.0 - Thread 2
« Reply #3749 on: 12/31/2008 10:21 PM »
 
  You know I'm a Direct convert, looking at the two designs now I don't see how you couldn't go with Direct.
  An awful lot of people agree with you.
 
 
Quote
How ever a lot of time has passed since that decision had to be made and one thing I do agree with Dr. Griffin is that you can't keep stopping every year and try to redesign the rocket or you'll end up with nothing.  That to me is my biggest fear.
  Dr Griffin is right in that once a decision is made, you press forward with it. Otherwise nothing gets done. However, if you study the history of how NASA projects are run, there are decision points all along the way that must get a pass or the program is either terminated or replaced. Throughout all of NASA's history this has been followed, and many a NASA project has been cut because at these decision points they couldn't pass the grade. This time is different however. There have been several points in this program where Ares-I couldn't pass the decision node. But instead of doing the right thing and changing the program, the decision standards were actually lowered to the point that the LV passed. NASA then happily announced to the world that the Ares project has passed yet another milestone. I don't think it's a stretch to call this hypocrisy. This has led many to believe, rightly or wrongly, that Dr Griffin's goal was not to implement the VSE, but to build and fly the Ares rocket which he designed before he was the Administrator, back in his Planetary society days. The clamor to change the program is a cry from people who know what's happening on the inside to return to a sane launch vehicle program so that we can get on with the VSE. What the fear is, and it is very real, is that when Ares goes down as many believe it will, it will take the entire VSE, and possibly the American manned spaceflight program, with it.
 
 
Quote
Second the whole idea that Direct is safer is misplaced imho, as Direct refers to safer in regards to the Orion capsule.  Orion will never fly if it's unsafe and Ares 1 was chosen because it was the safest launch vehicle they could produce which is something  I think needs to be recognized.
  No, DIRECT refers to safer in terms of the launch vehicle. By every measure that matters, the Jupiter-120 is a safer launch vehicle than the Ares-I. For example it doesn't have to execute an engine start at high altitude - there is no extra staging event as there is on Ares-I. Also, the Jupiter-120 uses two main engines and can actually experience an engine out event at 45 seconds after launch and still achieve orbit. Such an experience on the Ares would trigger an immediate abort. The Jupiter-120 uses the 4-segment SRB that NASA has been flying for 30 years and has literally tons of heritage data on. We know how that system works, while the Ares-I uses a totally new SRB with no history and no heritage. It only "looks" like the old SRB. There are many other examples, but the bottom line is that the Jupiter-120 "launch vehicle" is safer than the Ares-I "launch vehicle".
 
 

And this is the the sort of unbalanced advocacy that costs Direct credibility.

If adding a segment to an existing booster is a "totally new design" then what do you call a totally new design?

Jupiter 120  has three staging events, 2*SRB plus 1* Orion. Ares I has two.

Ares I removes a whole set of falure modes, like an SRB failure damaging the ET, or one SRB failing and sending the stack into a spin. Not so Jupiter 120.

Jupiter 120 has new load paths, new propulsion system, new Oxygen tank, new flight dynamics.

Engine out helps of you have a manufacturing defect in a particular engine. If you have a design or system problem, not so much.

Assume for sake of argument that Jupiter 120 is about as safe as Ares 1. Once Direct goes to the moon, you are no longer using Jupiter 120. You are using Jupiter 232, with an air start upper stage, and a more complex vehicle overall than Ares I.




Offline Mark S

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Re: DIRECT v2.0 - Thread 2
« Reply #3750 on: 12/31/2008 11:54 PM »

And this is the the sort of unbalanced advocacy that costs Direct credibility.

If adding a segment to an existing booster is a "totally new design" then what do you call a totally new design?

Jupiter 120  has three staging events, 2*SRB plus 1* Orion. Ares I has two.

Ares I removes a whole set of falure modes, like an SRB failure damaging the ET, or one SRB failing and sending the stack into a spin. Not so Jupiter 120.

Jupiter 120 has new load paths, new propulsion system, new Oxygen tank, new flight dynamics.

Engine out helps of you have a manufacturing defect in a particular engine. If you have a design or system problem, not so much.

Assume for sake of argument that Jupiter 120 is about as safe as Ares 1. Once Direct goes to the moon, you are no longer using Jupiter 120. You are using Jupiter 232, with an air start upper stage, and a more complex vehicle overall than Ares I.


Will,

    Unbalanced advocacy?  I thought that advocates always presented their positions in the best possible light.  Short of lying or fabricating the numbers, that is.  Have Ares advocates gone to any lengths to play up the pluses and minuses of Jupiter vs Ares?  Or isn't it always "we can't under the laws of physics prove their numbers" or "dual-launch EOR of identical vehicles is vastly overdesigned for ISS logistics", or some other such evasive wording or testimony.

    The new Ares-I five-segment SRB must be treated as a whole new design because: 1) The added segment changes the behavior and characteristics of the combustion chamber, and 2) The propellant's internal shape has also been changed, and 3) The nozzle and TVC have been modifed, and 4) NASA has never used an SRB as the sole first stage of a manned vehicle.  None of those concerns apply to J-120, since it uses the standard Space Shuttle SRB, in the standard Space Shuttle configuration.

    Ares-I has a whole new set of failure modes, like SRB thrust oscillation, residual thrust that could cause a collision after staging, second stage ignition failure modes, and probably more that I don't know about.

    Ares-I has a new booster stage, a totally new upper stage, new load paths, new J2-X engine, new avionics, new flight dynamics.  How is this an advantage for Ares-I over J-120?

     Having no engine-out capability at all doesn't help you in any circumstance.  If you have a design or system problem, it's even worse.

    When J-232 starts flying, we will already have four years of flight experience with J-120.  Safety of J-232 will still be within ESAS designated margins for manned launchers.

Have a happy new year!

Mark S.


Offline HIP2BSQRE

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Re: DIRECT v2.0 - Thread 2
« Reply #3751 on: 01/01/2009 01:51 AM »

And this is the the sort of unbalanced advocacy that costs Direct credibility.

If adding a segment to an existing booster is a "totally new design" then what do you call a totally new design?

Jupiter 120  has three staging events, 2*SRB plus 1* Orion. Ares I has two.

Ares I removes a whole set of falure modes, like an SRB failure damaging the ET, or one SRB failing and sending the stack into a spin. Not so Jupiter 120.

Jupiter 120 has new load paths, new propulsion system, new Oxygen tank, new flight dynamics.

Engine out helps of you have a manufacturing defect in a particular engine. If you have a design or system problem, not so much.

Assume for sake of argument that Jupiter 120 is about as safe as Ares 1. Once Direct goes to the moon, you are no longer using Jupiter 120. You are using Jupiter 232, with an air start upper stage, and a more complex vehicle overall than Ares I.


Will,

    Unbalanced advocacy?  I thought that advocates always presented their positions in the best possible light.  Short of lying or fabricating the numbers, that is.  Have Ares advocates gone to any lengths to play up the pluses and minuses of Jupiter vs Ares?  Or isn't it always "we can't under the laws of physics prove their numbers" or "dual-launch EOR of identical vehicles is vastly overdesigned for ISS logistics", or some other such evasive wording or testimony.

    The new Ares-I five-segment SRB must be treated as a whole new design because: 1) The added segment changes the behavior and characteristics of the combustion chamber, and 2) The propellant's internal shape has also been changed, and 3) The nozzle and TVC have been modifed, and 4) NASA has never used an SRB as the sole first stage of a manned vehicle.  None of those concerns apply to J-120, since it uses the standard Space Shuttle SRB, in the standard Space Shuttle configuration.

    Ares-I has a whole new set of failure modes, like SRB thrust oscillation, residual thrust that could cause a collision after staging, second stage ignition failure modes, and probably more that I don't know about.

    Ares-I has a new booster stage, a totally new upper stage, new load paths, new J2-X engine, new avionics, new flight dynamics.  How is this an advantage for Ares-I over J-120?

     Having no engine-out capability at all doesn't help you in any circumstance.  If you have a design or system problem, it's even worse.

    When J-232 starts flying, we will already have four years of flight experience with J-120.  Safety of J-232 will still be within ESAS designated margins for manned launchers.

Have a happy new year!

Mark S.

Please tone it down...

I think Mark is trying to say, if we look at the safety numbers of Ares I vs Direct 120, using the same criteria that Direct 120 would come ahead of the Ares I. 

If you want to stack the deck in anyone's favor, sure one vicheal can be made to look safer.  But with a fair scale, I feel Direct 120 comes out on top of Ares I. 

Remember, Direct can also carry a heavier cupsule with all the saftey features left in, that Ares cannot carry.  Even if we used the same capsule, I think that Direct would come out on top.  Direct can carry up to 20 tons of additional shielding that Ares cannot carry. 

If you were going into battle , would you rather be in the Hummve (Ares) or in an M1A1 tank  (Direct 120)t hat can carry that extra shielding.

If you want to compare Ares V with Direct 232, I still think that I would go with Direct. Ares V might be able to carry all that weight, but remember now new five segment SRBs, etc.  Direct is pretty much flying like the shuttle today expect for a capsule ontop of the tank and not the shuttle on the side.    I would really like to see the currant LOM numbers  for Ares V.  I would be very suprised if it is lower than Direct. 

At the end of the day, Direct would be flying 8+ missions/year, Ares V 2-4 missions/year.  The more you fly, the safer you can make the rocket.  There will be failures in Direct, like any other rocket, but I would trust more a rocket that has flies 8+ times a year, than one that  we will be luckly will fly 4+/years. 



Offline HIP2BSQRE

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Re: DIRECT v2.0 - Thread 2
« Reply #3752 on: 01/01/2009 02:05 AM »
Quote
The clamor to change the program is a cry from people who know what's happening on the inside to return to a sane launch vehicle program so that we can get on with the VSE. What the fear is, and it is very real, is that when Ares goes down as many believe it will, it will take the entire VSE, and possibly the American manned spaceflight program, with it.

Yes that is my biggest fear, one in which I'm willing to see Ares go forward in order to preserve.  As much as Direct is better over Ares, Ares is better than nothing and is quite capable of fulfilling VSE. 

And odd question but if Direct is shot down in the coming months (which I hope it's not) would the Direct team be willing to swallow the bullet and press ahead and try to make Ares as successful as possible in order to preserve American spaceflight?
 
Quote
  Yes, every rocket has its hurdles. But the timelines we have presented have been put together by the people at MSFC who do the scheduling of projects. It's NASA personnel that are saying we can do this. We are only relaying their conclusions.

Very reassuring, that's got to be a major strong point for the Direct case when presenting it to the powers that be.  Would Direct be willing to keep Dr. Griffin on board if he was willing in order to prevent a major political shake up with in the agency?  Stability will be key in seeing the program move forward with VSE.
 

Ares is better than nothing I agree.  Looking at Ares longterm though, even now I can see that Ares is a dead end.  NASA has great engineers and they do what you tell them to do.  But Ares's cost is going to cost NASA everything 8-10 years down the line.  Ares is already doing that with the science budget and it will only get worse.  Why was Apollo cancelled?  Yes, we got to the moon first, but also because of Apollos high cost.   

It is like asking your parents (Congress) to help buy two $100,000 cars and you make $30,000.  Yes--you can do it on pay as you go.  But guess what--you have very little money for anything else that you may wish to do.   You cannot fund that trip abroad (or visit that NEO) since there is no money.  But that is not the end of it, the cost to maintain thoses cars.  These cars need expensive upkeep and engineers, you need a new garage, new roads, they only take 91 fuel, etc  Now you are broke and can only afford to drive them once or twice a year.    So now you have very little, while your nieghbor who brought that smaller ford pickup, can do all those things.  But guess what, when you go crying back to your parents (congress) for more money, they will say NOPE!  You wasted all that money beforehand, tough luck.  That is NASA's future, which I do not want.

Offline Will

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Re: DIRECT v2.0 - Thread 2
« Reply #3753 on: 01/01/2009 02:48 AM »

And this is the the sort of unbalanced advocacy that costs Direct credibility.

If adding a segment to an existing booster is a "totally new design" then what do you call a totally new design?

Jupiter 120  has three staging events, 2*SRB plus 1* Orion. Ares I has two.

Ares I removes a whole set of falure modes, like an SRB failure damaging the ET, or one SRB failing and sending the stack into a spin. Not so Jupiter 120.

Jupiter 120 has new load paths, new propulsion system, new Oxygen tank, new flight dynamics.

Engine out helps of you have a manufacturing defect in a particular engine. If you have a design or system problem, not so much.

Assume for sake of argument that Jupiter 120 is about as safe as Ares 1. Once Direct goes to the moon, you are no longer using Jupiter 120. You are using Jupiter 232, with an air start upper stage, and a more complex vehicle overall than Ares I.


Will,

    Unbalanced advocacy?  I thought that advocates always presented their positions in the best possible light.  Short of lying or fabricating the numbers, that is.  Have Ares advocates gone to any lengths to play up the pluses and minuses of Jupiter vs Ares?  Or isn't it always "we can't under the laws of physics prove their numbers" or "dual-launch EOR of identical vehicles is vastly overdesigned for ISS logistics", or some other such evasive wording or testimony.

    The new Ares-I five-segment SRB must be treated as a whole new design because: 1) The added segment changes the behavior and characteristics of the combustion chamber, and 2) The propellant's internal shape has also been changed, and 3) The nozzle and TVC have been modifed, and 4) NASA has never used an SRB as the sole first stage of a manned vehicle.  None of those concerns apply to J-120, since it uses the standard Space Shuttle SRB, in the standard Space Shuttle configuration.

 

Tripe. Jupiter 120 has different load paths, different liquid engines, in a different location, with entirely different flight dynamics. It isn't the standard Shuttle configuration by any stretch of the imagination.

While I heartily disagree with your conclusions, I wish you a happy New Year. We both want to get more humans off Earth. We can argue about the way forward, but agree on the destination.

Offline Mark S

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Re: DIRECT v2.0 - Thread 2
« Reply #3754 on: 01/01/2009 02:52 AM »
While I heartily disagree with your conclusions, I wish you a happy New Year. We both want to get more humans off Earth. We can argue about the way forward, but agree on the destination.

Ditto that, Will.

Cheers!


Offline JMSC

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Re: DIRECT v2.0 - Thread 2
« Reply #3755 on: 01/01/2009 02:53 AM »
I think Will brings up some fair points.  You do have to run a balanced analysis concerning all aspects of mission safety.  On a simple Pro/Con list I would give the Jupiter 120 the nod for crew safety vs Ares I.  But as Will points out the J-232 does introduce an upper stage that will (according to safety estimates done by the DIRECT team) make it slightly less safe in terms of LOC than the Ares I.  Against this you have the balance the nearly $20 billion extra it would take to develop Ares I and V, the schedule lag of several years, the greater chance of a loss of mission due to the complexity of Ares V, and the lower total performance of using one 25 ton and 150 ton launcher per mission vs using two 100 ton class launchers for a DIRECT lunar mission.

Getting back too crew safety on a J-120 vs Ares I, I would say it is no competition between the two.  On Ares I side it does have simplicity going for it (2 engines vs 4 engines for the J-120) but thatís about its only real advantage.  The Jupiter uses 2-flight proven engines (existing shuttle SRM and RS-68).  The motors for ARES I are completely unproven (5-segment solids with a new PBAN mixture [essentially a new motor] and an unproven J-2X upper stage engine).  You also have an air startable engine (J-2X) vs a hold verify all engines are running and then launch procedure for Jupiter-120.  In addition thanks to the Jupiter being a rather pleasant looking squat shape it experiences much smaller dynamic loading than the stick like Ares I.  Jupiter can also carry an Orion with all safety features included vs the stripped down version being worked on for Ares.  It is also impossible to fully calculate the advantage of using a minimally modified shuttle stack, which has 123 flights and only one failure to its credit making the shuttle stack the most reliable launch vehicle developed by man.  Jupiterís use of the robust RS-68 and the elimination of the side mounted orbiter should only make an already very reliable system even more reliable.  There are many more safety advantages that the J-120 has over Ares I that are probably too numerous to list (such as the fact the Orion is separated by more than 10 meters from the fuel whereas in Ares I, Orion sits right on top of the hydrogen tank).  All in all even without doing a detailed LOC analysis the J-120 looks to be far superior to ARES I in terms of crew safety.

- John

Offline Jim

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Re: DIRECT v2.0 - Thread 2
« Reply #3756 on: 01/01/2009 02:55 AM »
Tripe. Jupiter 120 has different load paths, different liquid engines, in a different location, with entirely different flight dynamics. It isn't the standard Shuttle configuration by any stretch of the imagination.

Incorrect.  I am an EELV advocate but you are wrong. 

NLS inline aka Direct is a simple modification of the shuttle configuration and would not have any show stoppers
As for flight dynamics, they would be more benign
As for load paths, they are more straight forward and easier to analyze
Different engines don't matter since they are existing 

and the advantages of Direct ground ops is huge
« Last Edit: 01/01/2009 02:56 AM by Jim »

Offline Mark S

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Re: DIRECT v2.0 - Thread 2
« Reply #3757 on: 01/01/2009 03:39 AM »
I think Will brings up some fair points.  You do have to run a balanced analysis concerning all aspects of mission safety.
- John

Oh, I agree John.  I think everyone on the DIRECT team has been asking for an objective analysis and comparison of the currently available launch proposals since the beginning.  I wasn't around back then, but I have gone back and read the NSF threads, TSR articles, AIAA papers, etc.

And as soon as DIRECT 1.0 was first put forward, almost three years ago now, the answer they got was "no, we're too far down the road to start changing plans now."  Of course, that was when the Ares project was barely out of the gates, very much still a "paper rocket".

Now we are three years down the road, and many of the sunny predictions that the Ares project made have fallen flat, and many of the dire predictions that the DIRECT team made have come true.

One (other) thing that bothers me about Ares is when these issues are brought up, they are always just brushed aside by saying "All rockets have problems", and "Designing rockets is really hard", etc.  First, those answers seem flippant and condescending.  Second, this is not 1957 and we are not supposed to be figuring these things out as we go along.  What happened to all that "50 Years of NASA" experience?  Shouldn't we know at least a little bit about rocket design by now?

By my way of thinking, we have almost thirty years (out of fifty!) flying the Shuttle.  Yes, there were two horrible accidents, and we finally realized that the side-mount Shuttle can never be safe.  But that does not mean we have to abandon thirty years of experience, training, and data.  Ares does not leverage these resources, it is something new for the sake of being something new.

DIRECT went to extreme lengths to leverage every single aspect of the Shuttle heritage that they possibly could.  DIRECT listened to outside criticism and incorporated the necessary changes to make the project better.  DIRECT has had a three year gestation period of fine tuning and incremental improvements. 

DIRECT is fighting an uphill battle and only asks for an objective review.  Ares is projected as the only game in town, "it's my way or the highway".  Which project seems like it has something to hide?

Only time will tell.  Let us all hope that 2009 turns out better than 2008 for everyone!

Mark S.

« Last Edit: 01/01/2009 03:52 AM by Mark S »

Offline clongton

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Re: DIRECT v2.0 - Thread 2
« Reply #3758 on: 01/01/2009 03:56 AM »
Compare Jupiter-120 to Ares-I
Compare Jupiter-232 to Ares-V, not Ares-I

By the time we fly Jupiter-232 we will have YEARS of flight history of the Jupiter-120, which *IS* the first stage of the Jupiter-232.

What you are actually comparing is the Jupiter UPPER STAGE (the only new item) to the ENTIRE BRAND NEW ARES-V ROCKET!
« Last Edit: 01/01/2009 03:57 AM by clongton »
Chuck
You don't get to come back and try it later, so suck it up and get on the rocket.

Offline gladiator1332

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Re: DIRECT v2.0 - Thread 2
« Reply #3759 on: 01/01/2009 05:33 AM »
Well it is 2009 here (NJ)...let's hope this is the year of Jupiter. Good luck in the new year fellas.

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