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Topic: Beginning Of The End For Ares?
Username: Connies4ever
Posted 2008-10-28 02:37:51 and read 5838 times.

Another potentially fatal design flaw -- maybe. I guess optimists would say it's manageable, and pessimists would say scrap the whole thing and start over -- maybe with DIRECT.

http://www.space-travel.com/reports/...ws_found_in_Ares_I_rocket_999.html

But it would seem that Ares I is not ready for prime time. Maybe shuttle has more life left in it than previously thought.

Topic: RE: Beginning Of The End For Ares?
Username: TheSonntag
Posted 2008-10-28 06:27:52 and read 5792 times.

Scrap this crap and get something useful. The only bad thing is that the end of Ares I might also mean the end of Ares V, our ticket to the moon. But better stop it now. Orion can also fly on top of another rocket.

Topic: RE: Beginning Of The End For Ares?
Username: Thorny
Posted 2008-10-28 08:50:50 and read 5743 times.

It seems that every few weeks there is another "fatal blow" to Ares. I just wonder how many it will suffer before it really does die. How much more time and taxpayer dollars is NASA going to waste on this turkey?

On the other hand, others say that if there had been an internet around during Apollo, we'd all probably have been sniping about how bad Saturn V is, how the second stage is a hopeless engineering mess and how the third stage is a kludge that has to work okay on both Saturn IB and Saturn V and doesn't work particularly well for either, and oh my God, that pogo issue is gonna kill a crew, and don't get me started on single-engine out in the first three seconds being unsurvivable!  Smile

But I think the weight of evidence is building now to the point that Ares must be discarded. The only viable choice now is going to be Delta IV-Heavy. The Ares name has been so thoroughly discredited that NASA can no longer, in my opinion, shift to DIRECT (even if they call it Ares II) because it now looks very much as if NASA can't design a workable rocket even if given all the budget of the Pentagon (even assuming that's not true, its the appearance of this being the case that is going to kill a new NASA-designed rocket for the foreseeable future, as far as Congress is concerned.)

So look for the next President to kill Ares at the earliest opportunity, and with the economic conditions of the day, he will choose Delta IV (which will need a costly avionics upgrade, but that is a drop in the bucket compared to Ares I expenditures.) The lunar and Mars goals will be set aside for the foreseeable future. They won't be killed, but with Ares I gone so goes Ares V. When we get around to planning lunar missions again, probably 10 years from now, they'll be looking at the propellant depot concept and no mega-rockets.

Topic: RE: Beginning Of The End For Ares?
Username: Venus6971
Posted 2008-10-28 09:02:35 and read 5741 times.

Time to dust off the Saturn V plans and update them, proven technology with todays computers should be a no brainer but this the federal government we are talking about.

Topic: RE: Beginning Of The End For Ares?
Username: Thorny
Posted 2008-10-28 09:40:33 and read 5720 times.



Quoting Venus6971 (Reply 3):
Time to dust off the Saturn V plans and update them, proven technology with todays computers should be a no brainer but this the federal government we are talking about.

That would cost more than Ares. A lot more.

At least the parts for Ares are still in production around the country (except for the J-2 engine, which is turning out to be slow and expensive to put back into production.) Nobody has made parts for Saturn V since 1968. And the original Saturn V was anything but cheap (NASA's unofficial motto of Apollo was "waste anything but time") which is why LBJ and Congress said 'no' to building more in 1967.

Topic: RE: Beginning Of The End For Ares?
Username: TheSonntag
Posted 2008-10-28 14:59:23 and read 5583 times.



Quoting Venus6971 (Reply 3):
Time to dust off the Saturn V plans and update them, proven technology with todays computers should be a no brainer but this the federal government we are talking about.

Not going to work. Not only has all tooling gone, training the stuff again would take years, as well. And of course the electrical system, all other parts and so on have been designed to work with the 1960s technology computers, so you cannot just put a modern computer on it.

It "could" be possible, but by that time, you certainly have Ares V built. The problem does not rest with Ares V anyway, it is the Ares-I design which not only is ugly, but which everyone who knows about rocket technology seems to hate anyway.

Building a cool Nova rocket would be cool, though  Wink

Topic: RE: Beginning Of The End For Ares?
Username: Flighty
Posted 2008-10-28 17:56:34 and read 5515 times.

We should also build giant wooden frigates to sail around the world and retake the seas for His Majesty's Navy! No seriously, we have some very tall trees that will make masts for an excellent new fleet of pointless ships that can re-enact the past... because.... it's cool to do that. Am I missing something?

Topic: RE: Beginning Of The End For Ares?
Username: Cloudy
Posted 2008-10-29 17:11:37 and read 5278 times.

There were people who liked Ares I when it was just going to be a 4 segment SRB with a modified SSME on the 2nd stage. It seems like the only people defending it now, however, are those with some sort of official stake in the program. Just about everyone who knows something and is able to speak freely seems to prefer Direct or EELV. The only reason Ares I seems to be to create an early requirement for the J2X and the 5 segment SRB - smoothing the path to the Ares V.

The cost of a sustained human exploration program on the the moon and Mars is just going to be too high for the public to stomach if we have to use conventional rockets and nobody else threatens to do it first. A sortie to a near earth asteroid or a space telescope at one of the Legrange points seems to be the best that can be hoped for - even if Ares I is replaced by Direct's Jupiter. We need VASIMR or an advanced ion drive, or a nuclear thermal rocket.
The problem with these so far has been low thrust/weight ratio and lack of in space experience - but that has been slowly changing. The ion drive is finally matured enough to be considered a low risk option for deep space missions such as Dawn.

The problems we are having with Ares I would be defensible if we were doing something fundamentally new, as was done in the shuttle and Saturn programs. But Ares I only seeks to build a new booster in the same class as Atlas V and Delta IV, with no major cost or safety advantage. A program with as much cost and risk as Ares I ought to have a much higher payoff then that.

Topic: RE: Beginning Of The End For Ares?
Username: Thorny
Posted 2008-10-29 17:45:29 and read 5259 times.



Quoting Cloudy (Reply 7):
There were people who liked Ares I when it was just going to be a 4 segment SRB with a modified SSME on the 2nd stage.

I was one of them. The many, many changes since then have just taken it too far from that original concept. NASA should have pulled the plug long ago, but it has supporters way up on high, and the guys in the trenches are being told to shut up and color.

Quoting Cloudy (Reply 7):

The cost of a sustained human exploration program on the the moon and Mars is just going to be too high for the public to stomach if we have to use conventional rockets

Maybe, that depends on the cost of the individual rockets. Using the fuel depot concept and a successful low-cost launcher like Falcon 9, there is nothing fundamentally unaffordable about it. We just have to want to do it. Bonus points: the fuel depot concept allows foreign participation quite easily, i.e., "Japan provides 20% of the propellant of the depot and gets 20% of the crew time on the moon" or what-have-you.

Quoting Cloudy (Reply 7):
The problems we are having with Ares I would be defensible if we were doing something fundamentally new

They more or less are. What exactly in Ares I is already in use? The SRB casings? That's about the entirety of it now, and they're talking about switching even them to new composites!

Topic: RE: Beginning Of The End For Ares?
Username: SCAT15F
Posted 2008-10-29 18:15:19 and read 5255 times.

A human-rated Delta 4 is the way to go. Solid propellant is the most inefficient type of chemical/conventional propulsion there is- LOX/LH2 is the most efficient.

Topic: RE: Beginning Of The End For Ares?
Username: Thorny
Posted 2008-10-29 18:59:35 and read 5243 times.



Quoting SCAT15F (Reply 9):
Solid propellant is the most inefficient type of chemical/conventional propulsion there is- LOX/LH2 is the most efficient.

Not for a first stage. LOX/RP-1 (kerosene) is better. LH2 requires huge tankage and heavy insulation, hurting t/w ratios, and ground handling is more difficult.

I'd say Atlas V would be the better engineering choice for NASA, but the Russian engine is just too much for Congress to sign off on, so Delta IV it is (even if Mitsubishi makes some of the tankage, that's a lot easier for Congress to buy into than a Russian engine being in the critical path for national prestige missions.)

Topic: RE: Beginning Of The End For Ares?
Username: Connies4ever
Posted 2008-10-30 03:14:37 and read 5173 times.



Quoting Thorny (Reply 10):
I'd say Atlas V would be the better engineering choice for NASA, but the Russian engine is just too much for Congress to sign off on, so Delta IV it is (even if Mitsubishi makes some of the tankage, that's a lot easier for Congress to buy into than a Russian engine being in the critical path for national prestige missions.)

Atlas V is indeed impressive with the Russian engines. To thwart the national security argument, could not the US enter into a license-production agreement with the Russians on this ? (Apologies if this is already the case, I simply don't know.)

Topic: RE: Beginning Of The End For Ares?
Username: TheSonntag
Posted 2008-10-30 06:54:43 and read 5143 times.

Slightly off topic, but why did the russians always invest into RP-1 powered engines, while the US largely abandoned this market (the F-1 had no successor, for example)?

Topic: RE: Beginning Of The End For Ares?
Username: SCAT15F
Posted 2008-10-30 08:31:29 and read 5102 times.

Rocketdyne did some work on the RS-84, an 800,000 lb thrust Lox/RP-1 engine in the '90s, but they never built it.

Topic: RE: Beginning Of The End For Ares?
Username: Thorny
Posted 2008-10-30 08:39:54 and read 5102 times.



Quoting Connies4ever (Reply 11):
Atlas V is indeed impressive with the Russian engines. To thwart the national security argument, could not the US enter into a license-production agreement with the Russians on this ? (Apologies if this is already the case, I simply don't know.)

That was the plan if LockMart won the EELV contract. They didn't, instead the Air Force gave the contract to both Boeing and LockMart, and the resulting low flight rate made license production of the engine unaffordable. LockMart and Aerojet quietly abandoned the effort earlier this year. NASA's need for two or three engines a year isn't enough to change that.

Officially, Delta IV is the backup to Atlas V if the Russians block further sales of the engine due to some future foreign policy argument, but that option won't be available to NASA, which will have to tailor the Orion to one EELV or the other. So Delta IV is the only politically acceptable alternative of the EELVs.

Topic: RE: Beginning Of The End For Ares?
Username: SCAT15F
Posted 2008-10-30 10:22:56 and read 5071 times.



Quoting Thorny (Reply 14):
So Delta IV is the only politically acceptable alternative of the EELVs.

The other issue is that the (required for the CEV) Atlas V heavy (three core stages) has not even got off the drawing board yet, and it won't as long as the Delta 4 heavy works.

Topic: RE: Beginning Of The End For Ares?
Username: Stitch
Posted 2008-10-30 16:58:11 and read 4980 times.

I admit I was surprised when NASA chose LM over Boeing, since the former has little to no man-rated launch vehicle experience and Boeing has plenty - both on it's own and from it's purchase of Rockwell.

Of course, Boeing has made a royal mess of the sat recon program it beat LM out for, so I guess both NASA and DOD/NRO are learning that picking someone new in the hopes of "something different" doesn't mean that something is usable.

Give Boeing the manned contract and LM the recon and let both continue to do what they do best.

Topic: RE: Beginning Of The End For Ares?
Username: Thorny
Posted 2008-10-30 17:55:26 and read 4955 times.



Quoting Stitch (Reply 16):
I admit I was surprised when NASA chose LM over Boeing, since the former has little to no man-rated launch vehicle experience and Boeing has plenty - both on it's own and from it's purchase of Rockwell.

If we're talking about the launch vehicle Ares, ATK (formely Thiokol) does the first stage and Boeing has the second stage. Pratt & Whitney/Rocketdyne has the second stage engine.

LockMart has the CEV (Orion), but that's not where NASA's problem is, the problem is Ares. The only problem CEV has is that every time they think they have the design nailed down, they find out Ares has yet another problem and LM has to go back to the drawing board to deal with it.

Topic: RE: Beginning Of The End For Ares?
Username: PC12Fan
Posted 2008-11-03 05:00:55 and read 4662 times.

Thorny,

I may have simply over looked your input on Direct, but wouldn't this be the best option? Or is it that NASA doesn't want it to save face.

Topic: RE: Beginning Of The End For Ares?
Username: DfwRevolution
Posted 2008-11-03 07:54:00 and read 4631 times.



Quoting Thorny (Reply 14):
NASA's need for two or three engines a year isn't enough to change that.

If a big Orion like the one we have now was riding on an Atlas V Heavy, that's 3 engines per launch. If we maintain a biannual ISS crew rotation or eventually biannual lunar sorties, that's 6 more engines per year. If during the lunar phase, the Atlas V heavy was again used to park the dry EDS/LASM (on separate flights) that's an additional 12 engines. So if Atlas V Heavy were used for the critical components of a lunar architecture (and fuel road something like Falcon 9), we would be looking at 18 more engines per year. Perhaps with a bit more economy of scale from cranking out 18 additional cores the commercial side would see a more activity, too.

Just playing devils advocate, but I don't think it would be impossible to stimulate either EELV to a healthy flight rate in short order.

Topic: RE: Beginning Of The End For Ares?
Username: Thorny
Posted 2008-11-03 10:13:05 and read 4606 times.



Quoting PC12Fan (Reply 18):
I may have simply over looked your input on Direct, but wouldn't this be the best option? Or is it that NASA doesn't want it to save face.

I used to think so, but now my regard for NASA's ability to design and field a launcher is so low, I'm not at all sure they can pull it off. Worse, after killing Ares, the President and Congress will have to agree to let NASA try again with a new vehicle like DIRECT or just go off-the-shelf with EELV. WIth NASA's totally botched Ares development program, I don't see the politicians giving NASA a second chance (or third, after the X-33 debacle a decade ago) with their own all-new system. So EELV (or perhaps, just maybe Falcon/Dragon) is all that's left.

Quoting DfwRevolution (Reply 19):
If a big Orion like the one we have now was riding on an Atlas V Heavy, that's 3 engines per launch. If

True, but only if we need the -Heavy version. With Atlas V, it isn't clear that we do, especially if they go back to the drawing board after Ares is killed off and Orion is tailored to EELV (which they'll have to do to one degree or another anyway.)

Quoting DfwRevolution (Reply 19):
Just playing devils advocate, but I don't think it would be impossible to stimulate either EELV to a healthy flight rate in short order.

Yes, it almost certainly would, that's one of the advantages of the approach. But would it be enough to warrant a US-based RD-180 engine plant? I doubt it, and it will be a hard sell with Congress, which would rather not send even more money to Russia or pay the huge factory startup costs (that Aerojet will have to pass on to the government) and just use off-the-shelf RS-68, which is already in an improvement program.


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