Direct (Jupiter) v. Ares...the debate continues

[joeybigO]

check that sorry and thanks for the recovery, check the RD-170 engine.

link here

 

[Urwumpe]

RD-0120 would also fit as SSME replacement, this is a bit more expensive as the RS-68, but one of the best researched rocket engines in the world - only the SSME has more test data available. It is far more effective as the RS-68, thanks to a pretty ingenious staged combustion cycle.

The information from the RD-0120 was used for improving both SSME and RS-68, though the knowledge of optimizing turbopumps still got left in Russia.

http://www.astronautix.com/engines/rd0120.htm

EDIT: Before all think, swapping engines on Ares or Direct will be a cool idea - even the change from SSME to RS-68 is already a critical problem, as the RS-68 requires different ground equipment for starting as the SSME.

 

[GregBurch]

I just want to mention, in reality echo the voices on NasaSpaceFlight, that too much blame is placed on NASA and not enough on the presentation of Direct.

For me, it's not so much that Direct is such a great design, it's that the whole Ares/Orion program design is soooo bad. Just off the top of my head (and in no particular order), here are a few of the major criticisms I have of the Ares/Orion program design:

• We have two great, proven launchers in the EELV rockets. NASA rejected them out of hand as "not man-rated" in order to develop two new rockets that are not man-rated (because they didn't even exist at the time the program was designed).
• We've spent billions developing very effective on-orbit assembly techniques with ISS. NASA didn't incorporate any of this technology or knowledge into the Ares/Orion program design.
• We've spent billions learning about reusability of space systems with STS. NASA developed a completely throw-away system with Ares/Orion.
• NASA knew the day would come when STS would have to be retired for years, but postponed developing a successor program until the short time available became one of the major design constraints.
• NASA spent time and money developing the X-38 to a very high level as a ACRV, which could have been easily continued on into a good crew transfer vehicle. But it was ditched so that it's Orion would have to be developed as a crew transfer vehicle.

There's more, and none of it has to do with the positives that are involved in Direct. Much of the criticism of Direct as (possibly) having too little lofting power goes away if you accept that using on-orbit assembly and fuel storage should be part of any robust space infrastructure system.

My disgust with NASA as a political pig trough had reached a critical level before Ares/Orion was conceived. Ares /Orion is just the bitter icing on the cake.

 

[Urwumpe]

GregBurch: 100% ACK on this one, great summary of the criticisms.

 

[AstroCam]

Even though i'm an aussie, and therefore don't have to pay for ares, it just seems so BAD.

I mean, working on a air launched TSTO vehicle, or a starclipper style shuttle vehicle would be the way to go.

With ares, at the very LEAST they should have kept the land recovery option - there is no way you can reuse and refurbish a tin can full of sensitive electronics after dunking it in saltwater for several hours.

*sigh* if we can generate the same amount of hype that surrounded the first apollo landing, but with a mars shot, we should be able to save manned spaceflight....

If only the Deltaglider existed in real life.

 

[Arrowstar]

Frankly, there are days I think SpaceX would have a better chance of getting to the moon (if they so chose) than NASA will. *sigh*

 

[GregBurch]

*sigh* if we can generate the same amount of hype that surrounded the first apollo landing, but with a mars shot, we should be able to save manned spaceflight....

"We" most certainly can save manned space flight. But not with the political process and not through national/state bureaucracies. That way has played itself out to an end-game that has become a net negative force acting on space development.

The sooner the plug gets pulled on the current national manned program and those resources (or even a fraction of them) are channeled toward private endeavors, the sooner we'll get back to making progress.

Frankly, there are days I think SpaceX would have a better chance of getting to the moon (if they so chose) than NASA will. *sigh*

Some venture involving SpaceX is far, far more likely to put the next humans on the moon than the claptrap NASA is doing.

 

[dougkeenan]

Do private endeavors in space mean the private sector will service military space requirements?

 

[GregBurch]

Do private endeavors in space mean the private sector will service military space requirements?

Not necessarily. After all, the Air Force doesn't build its own airplanes.

 

[dougkeenan]

True but it does specify them. (I'm not trying to be difficult, just getting a grip on your vision.) If a return to the moon is specified but no private contractor wants to play, do we punt?

 

[GregBurch]

True but it does specify them. (I'm not trying to be difficult, just getting a grip on your vision.) If a return to the moon is specified but no private contractor wants to play, do we punt?

Well, my first reply to that would be that we should cross that bridge when we come to it, since trying to recast the national manned state space effort as a purchaser of specified goods and services as much as possible hasn't been tried, and it's worked in the closely related realm of satellite launch services.

Second, there were plenty of industry proposals out there prior to the VSE/Ares/Orion nightmare.

Third, since NASA is demonstrably failing to deliver by pursuing its model of doing it all in-house, at an enormous waste of taxpayer dollars, even so great a space development enthusiast as me would ask the question of whether the ends justify THESE means -- in other words, doesn't a point come where doing something poorly is worse than not doing it at all? As far as I and many, many others are concerned, the Ares/Orion screw-up is the final proof that that point has been reached. In my book, it was reached when the X-38 was killed. For me, that was the last straw.

For me, NASA is no longer something I love despite its flaws. It has become the number one enemy of space development.

 

[Zatnikitelman]

Greg, I don't suppose you've got a Phd in "Why NASA sucks and the inadequacies of their current program?"

NASA has basically lost all my support going with this stupid rocket design. Frankly, it's not even Orion that's the big problem, it's just the stupid launch vehicle. A vehicle that only sees about 8 minuts of glory before being cast off into oblivion. I got to see a mockup of the interior of the Orion capsule last weekend at the Huntsville Space and Rocket Center and I gotta say, it looked great! Orion's basically a success if they could stop hacking it off piece by piece to make up for a flying piece of crap launcher.

 

[GregBurch]

Greg, I don't suppose you've got a Phd in "Why NASA sucks and the inadequacies of their current program?"

:rofl:In a sense, I do: Three of the main passions in my life are space development, history and political philosophy and policy. The slow-motion train wreck that has been NASA since the beginning of the STS era has been for me like watching a beloved friend succumb to drug addiction. You see the self-destructive behavior, the rationalizations, the lack of insight into the problem that's killing your friend, the friend who used to be so bright and full of promise ... and nothing anyone says or does, and no amount of waking up and not knowing how they got into jail seems to make a difference. Finally the day comes where you sadly shrug your shoulders and say, "Enough!" NASA is beyond help.

NASA has basically lost all my support going with this stupid rocket design. Frankly, it's not even Orion that's the big problem, it's just the stupid launch vehicle. A vehicle that only sees about 8 minuts of glory before being cast off into oblivion. I got to see a mockup of the interior of the Orion capsule last weekend at the Huntsville Space and Rocket Center and I gotta say, it looked great! Orion's basically a success if they could stop hacking it off piece by piece to make up for a flying piece of crap launcher.

Yes -- by itself, Orion is OK. Nothing to write home about, and nothing we couldn't have done in 1975, but OK.

 

[Andy44]

I like the Air Force / DOD model of doing spaceflight: they didn't design the EELV's or the Delta II in house, they paid Lockheed and Boeing to build them rockets according to their specs, and we now have very good, reliable, and relatively cheap launchers. The old Titan series had run its course, after a good run, but it was an old system and too costly, and the EELV has replaced it nicely. The Air Force carries on with business. USAF was also smart enough to cut its losses with STS after it became apparent that it wouldn't be cost-effective.

I'm not a big fan of U.S. defense spending or government spending in general, but it certainly offers a valuable alternative to compare managment of NASA with, all the more so since both USAF space and NASA work for the same government, use the same contractors, use some of the same facilities, and grew up together in the 1950-60s side by side.

Of course, it helps that the USAF has real missions with a real purpose, while NASA's main mission is to "do glorious stuff" to pump up their budget.

 

[GregBurch]

I'm not a big fan of U.S. defense spending or government spending in general, but it certainly offers a valuable alternative to compare managment of NASA with, all the more so since both USAF space and NASA work for the same government, use the same contractors, use some of the same facilities, and grew up together in the 1950-60s side by side.

Yeah -- this has been a useful discussion, because I can now add another stanza of bitterness to my symphony of sorrow about NASA: As inefficient as the US defense procurement process is, it's a model of efficiency compared to NASA.

 

[Kodiak]

:rofl:In a sense, I do: Three of the main passions in my life are space development, history and political philosophy and policy. The slow-motion train wreck that has been NASA since the beginning of the STS era has been for me like watching a beloved friend succumb to drug addiction. You see the self-destructive behavior, the rationalizations, the lack of insight into the problem that's killing your friend, the friend who used to be so bright and full of promise ... and nothing anyone says or does, and no amount of waking up and not knowing how they got into jail seems to make a difference. Finally the day comes where you sadly shrug your shoulders and say, "Enough!" NASA is beyond help.

:speakcool: Thats a pretty grim picture you painted there Greg
I have to say though that NASA has changed considerably since the STS era mostly thanks to the internet. nasa could almost almost get away with murder in 80's, and early 90's. Nasa informing the public on its programs consisted of mostly 2 - 5 page pamphlets with pretty pictures and meaningless words. When Bush sr announced the Space Exploration Initiative, NASA bought a 3 page ad in popular mechanics, that consisted of nothing but gibberish. Space nuts would have a hell a time trying to tell the difference between a toilet brush, and a nasa program. however now is a whole different story, Nasa cannot get away with business as usual. Anytime there is even minor hiccup in project constellation, Space nuts are generally informed and go to town about it in the forums.

 

[Swatch]

In defense of the decision not to use the HHLV...

• when designed, they were designed to lower safety factors, which while possible to re-qualify, becomes a quagmire if numerous structural pieces need redesigning (beefy structure increases weight decreases payload).
• I know one of the two (Delta I believe) follows a non-optimal ascent profile that results in over 5G's at launch.
• They aren't exactly proven designs. 1 with a 50% success/failure, 1 unlaunched.

I do agree that DIRECT has some impressive design claims, but ignoring disagreements on performance, it appears to be a better method of looking at developing a Shuttle-derived launch vehicle.

ARES however is drowning under its own designs.

 

[GregBurch]

In defense of the decision not to use the HHLV...

• when designed, they were designed to lower safety factors, which while possible to re-qualify, becomes a quagmire if numerous structural pieces need redesigning (beefy structure increases weight decreases payload).
• I know one of the two (Delta I believe) follows a non-optimal ascent profile that results in over 5G's at launch.
• They aren't exactly proven designs. 1 with a 50% success/failure, 1 unlaunched.

I do agree that DIRECT has some impressive design claims, but ignoring disagreements on performance, it appears to be a better method of looking at developing a Shuttle-derived launch vehicle.

ARES however is drowning under its own designs.

Almost all of these criticisms could have been leveled at the military missiles NASA used for its first three manned launchers (Redstone, Atlas, Titan). The example of the work that was done toward developing the Titan IIIc as a launcher for the X-20 presents a good precedent for how the EELV family could have adopted a development pathway toward man-rating during their own development.

As for the over-G on one of the EELVs, I don't doubt that addressing that issue would have been FAR cheaper and provided a more robust solution to the task of getting people and their stuff into orbit than the Ares junkpiles.

And lest anyone think that the spacecraft in this train wreck are exempt from the same kinds of criticisms, check this out:

http://www.flightglobal.com/article...air-engine-faces-landing-abort-challenge.html

It looks like the Altair lander has a significant design flaw in its basic configuration. I don't doubt that this is fixable, but at what mass cost cascading down the Ares V/TLI design?

 

[GregBurch]

I have to say though that NASA has changed considerably since the STS era mostly thanks to the internet. nasa could almost almost get away with murder in 80's, and early 90's. Nasa informing the public on its programs consisted of mostly 2 - 5 page pamphlets with pretty pictures and meaningless words. When Bush sr announced the Space Exploration Initiative, NASA bought a 3 page ad in popular mechanics, that consisted of nothing but gibberish. Space nuts would have a hell a time trying to tell the difference between a toilet brush, and a nasa program. however now is a whole different story, Nasa cannot get away with business as usual. Anytime there is even minor hiccup in project constellation, Space nuts are generally informed and go to town about it in the forums.

Here's what gets me -- even in this wonderfully open and democratic new Internet age, NASA doesn't really seem to be changing the most important element of its culture, which is how over-all space development policy is developed. I would argue that they have the same high-priest trying to satisfy every political constituency mentality in this key area they always have.

 

[Moonwalker]

It's questionable if there are serious engineers who develope something in their spare time which is not being developed by NASA while they are developing Ares in their working time. It doesn't make sense to me. We're talking about an article, not about serious and official work I think. People can do what they want to in their spare time...

Talking about facts, development of Ares is moving very fast. Compared to the development of the Shuttle (hundreds or even thousands of lost tiles during atmospheric test flight, exploded main engines during ground tests and so on...) Ares seems to become cold reality too like the Shuttle once. I'm not pessimistic anymore when I look to all the tests within the last month and the progress...