Author Topic: Ares I with lighter upper stage engines  (Read 12579 times)

Offline Nathan

  • Member
  • Full Member
  • ****
  • Posts: 710
  • Sydney
  • Liked: 16
  • Likes Given: 3
Ares I with lighter upper stage engines
« on: 10/27/2009 09:17 am »
Given that one of the peices of hardware that will take the longest to develop is the Ares I upper stage engine J2X I was wondering whether an available alternative could be used?
For example - could a cluster of RL10 engines be used? They are lightweight. Is there a sweet spot between weight, thrust and number of engines that could work?
Volume would be an issue, requiring a wider engine area.
Are there any other engines that could be used? What about international options? LE5B?

If an existing engine could be used then the timetable could be bought forward.
Given finite cash, if we want to go to Mars then we should go to Mars.

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10560
  • Liked: 807
  • Likes Given: 40
Re: Ares I with lighter upper stage engines
« Reply #1 on: 10/27/2009 10:15 am »
There are no reasonable alternatives for this vehicle except an air-start SSME.

This thread should be in the Ares-I section.

Ross.
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline William Barton

  • Senior Member
  • *****
  • Posts: 3487
  • Liked: 8
  • Likes Given: 0
Re: Ares I with lighter upper stage engines
« Reply #2 on: 10/27/2009 10:23 am »
There are no reasonable alternatives for this vehicle except an air-start SSME.

This thread should be in the Ares-I section.

Ross.

For it's stated mission (seems to be short on payload even for that), but I'm curious: What does 5seg + ACES-41 do? Or could it manage ACES-71? I'm not suggesting it's a good idea, just wondering.

Offline Nathan

  • Member
  • Full Member
  • ****
  • Posts: 710
  • Sydney
  • Liked: 16
  • Likes Given: 3
Re: Ares I with lighter upper stage engines
« Reply #3 on: 10/27/2009 10:27 am »
There are no reasonable alternatives for this vehicle except an air-start SSME.

This thread should be in the Ares-I section.

Ross.

If anyone knows how to move the thread please do so.

What about a completely different upper stage based on 3xRD-120 engines?
Given finite cash, if we want to go to Mars then we should go to Mars.

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10560
  • Liked: 807
  • Likes Given: 40
Re: Ares I with lighter upper stage engines
« Reply #4 on: 10/27/2009 11:56 am »
For it's stated mission (seems to be short on payload even for that), but I'm curious: What does 5seg + ACES-41 do? Or could it manage ACES-71? I'm not suggesting it's a good idea, just wondering.

It drops into the Ocean somewhere short of the European/African coastline because it doesn't have *close* to the necessary thrust required to get it into orbit from the point where that first stage places it (in velocity/altitude terms).

Also, ACES-41 is lighter, so the First Stage acceleration and Max-Q would get significantly worse too.

J-2X is actually underpowered for this configuration and in order to pick up correct acceleration levels after FS jettison, you would require 12 RL-10B-2's to match its thrust levels.

Ross.
« Last Edit: 10/27/2009 12:00 pm by kraisee »
"The meek shall inherit the Earth -- the rest of us will go to the stars"
-Robert A. Heinlein

Offline Downix

  • Senior Member
  • *****
  • Posts: 7082
  • Liked: 22
  • Likes Given: 1
Re: Ares I with lighter upper stage engines
« Reply #5 on: 10/27/2009 12:22 pm »
For it's stated mission (seems to be short on payload even for that), but I'm curious: What does 5seg + ACES-41 do? Or could it manage ACES-71? I'm not suggesting it's a good idea, just wondering.

It drops into the Ocean somewhere short of the European/African coastline because it doesn't have *close* to the necessary thrust required to get it into orbit from the point where that first stage places it (in velocity/altitude terms).

Also, ACES-41 is lighter, so the First Stage acceleration and Max-Q would get significantly worse too.

J-2X is actually underpowered for this configuration and in order to pick up correct acceleration levels after FS jettison, you would require 12 RL-10B-2's to match its thrust levels.

Ross.
What about with the AJ-26-59?

It's thrust is 25% higher than the J-2X, but it's isp is 35% lower, so dunno if it is a substitute.  Altho, if you used 2 AJ-26-59, would give plenty of lift, yes?  And we'd have plenty of pre-built engines thanks to leftover Russian models.  But then it would have the same political issues as the Atlas V.
chuck - Toilet paper has no real value? Try living with 5 other adults for 6 months in a can with no toilet paper. Man oh man. Toilet paper would be worth it's weight in gold!

Offline Antares

  • ABO^2
  • Senior Member
  • *****
  • Posts: 5181
  • Done arguing with amateurs
  • Liked: 371
  • Likes Given: 228
Re: Ares I with lighter upper stage engines
« Reply #6 on: 10/27/2009 03:35 pm »
Non-starter.  The gravity losses from carrying RP1 instead of LH2 would be huge.
If I like something on NSF, it's probably because I know it to be accurate.  Every once in a while, it's just something I agree with.  Facts generally receive the former.

Offline Lars_J

  • Senior Member
  • *****
  • Posts: 6160
  • California
  • Liked: 677
  • Likes Given: 195
Re: Ares I with lighter upper stage engines
« Reply #7 on: 10/27/2009 03:46 pm »
Hmmm... Perhaps using an SRB as a first stage in an inline rocket is not such a great idea, if it places such extreme requirements on the 2nd stage.

If only this could have been predicted. :D :D :D

Offline Downix

  • Senior Member
  • *****
  • Posts: 7082
  • Liked: 22
  • Likes Given: 1
Re: Ares I with lighter upper stage engines
« Reply #8 on: 10/27/2009 03:59 pm »
Hmmm... Perhaps using an SRB as a first stage in an inline rocket is not such a great idea, if it places such extreme requirements on the 2nd stage.

If only this could have been predicted. :D :D :D
I know, if only someone had made mention of it sooner, and prepared a complete, well thought out program that could stand on it's own to replace this concept....
chuck - Toilet paper has no real value? Try living with 5 other adults for 6 months in a can with no toilet paper. Man oh man. Toilet paper would be worth it's weight in gold!

Online mmeijeri

  • Senior Member
  • *****
  • Posts: 7772
  • Martijn Meijering
  • NL
  • Liked: 397
  • Likes Given: 822
Re: Ares I with lighter upper stage engines
« Reply #9 on: 10/27/2009 04:01 pm »
Especially one that was already available commercially...
Pro-tip: you don't have to be a jerk if someone doesn't agree with your theories

Offline Archibald

  • Senior Member
  • *****
  • Posts: 2611
  • Liked: 500
  • Likes Given: 1096
Re: Ares I with lighter upper stage engines
« Reply #10 on: 10/27/2009 04:05 pm »
Hmmm... Perhaps using an SRB as a first stage in an inline rocket is not such a great idea, if it places such extreme requirements on the 2nd stage.

If only this could have been predicted. :D :D :D
I know, if only someone had made mention of it sooner, and prepared a complete, well thought out program that could stand on it's own to replace this concept....

I had some similar, mixed feelings ten minutes ago looking at the Ares 1 scrub thread.

The astonishment of seeing "real" Constellation hardware on the launch pad, imediately balanced by "wow, this thing is sure ugly. Not very efficient. And dummy upper stage. And the program may be cancelled soon.
Hell, how do we ended with this thing on LC-39 ?
ho, yes, ATK lobby, plus the need to reuse shuttle hardware. Plus commonality with Ares V.
Sigh...
Han shot first and Gwynne Shotwell !

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 15391
    • Space Launch Report
  • Liked: 8565
  • Likes Given: 1356
Re: Ares I with lighter upper stage engines
« Reply #11 on: 10/27/2009 04:18 pm »
Non-starter.  The gravity losses from carrying RP1 instead of LH2 would be huge.

The original ATK inline concepts included a J-2S powered LH2 upper stage able to lift 16-18 tonnes to LEO and a kerosene upper stage loaded with 113 tonnes of propellant able to lift 13 tonnes to LEO, both on top of 4-segment boosters.  (The original "Stick" was proposed well before ESAS and lunar exploration was in the mix.  It was just going to be an ISS transporter, with much lower mass requirements.)   

So yes, kerosene upper stage and/or smaller LH2 upper stage could work just fine, but would not be able to lift as much mass to orbit as Ares I. 

 - Ed Kyle
« Last Edit: 10/27/2009 04:19 pm by edkyle99 »

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 15391
    • Space Launch Report
  • Liked: 8565
  • Likes Given: 1356
Re: Ares I with lighter upper stage engines
« Reply #12 on: 10/27/2009 04:24 pm »
The astonishment of seeing "real" Constellation hardware on the launch pad, imediately balanced by "wow, this thing is sure ugly.

Beauty is in the eye of the beholder.

 - Ed Kyle

Offline Herb Schaltegger

Re: Ares I with lighter upper stage engines
« Reply #13 on: 10/27/2009 04:39 pm »
The astonishment of seeing "real" Constellation hardware on the launch pad, imediately balanced by "wow, this thing is sure ugly.

Beauty is in the eye of the beholder.

 - Ed Kyle

Or not. Behold: "The Corndog."  :-\
Ad astra per aspirin ...

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 15391
    • Space Launch Report
  • Liked: 8565
  • Likes Given: 1356
Re: Ares I with lighter upper stage engines
« Reply #14 on: 10/27/2009 05:03 pm »
The astonishment of seeing "real" Constellation hardware on the launch pad, imediately balanced by "wow, this thing is sure ugly.

Beauty is in the eye of the beholder.

 - Ed Kyle

Or not. Behold: "The Corndog."  :-\

As opposed to, say, this ungainly conglomeration?

 - Ed Kyle

Offline Lars_J

  • Senior Member
  • *****
  • Posts: 6160
  • California
  • Liked: 677
  • Likes Given: 195
Re: Ares I with lighter upper stage engines
« Reply #15 on: 10/27/2009 05:05 pm »
[re: Ares 1-X and STS images] Neither should win any beauty prizes. ;)
« Last Edit: 10/27/2009 05:05 pm by Lars_J »

Offline Antares

  • ABO^2
  • Senior Member
  • *****
  • Posts: 5181
  • Done arguing with amateurs
  • Liked: 371
  • Likes Given: 228
Re: Ares I with lighter upper stage engines
« Reply #16 on: 10/27/2009 08:27 pm »
Non-starter.  The gravity losses from carrying RP1 instead of LH2 would be huge.
1) The original ATK inline concepts included a J-2S powered LH2 upper stage able to lift 16-18 tonnes to LEO and a kerosene upper stage loaded with 113 tonnes of propellant able to lift 13 tonnes to LEO, both on top of 4-segment boosters.

2) would not be able to lift as much mass to orbit as Ares I.

1) And look at how well the performance predictions of subsequent ATK inline concepts have turned out

2) so, yeah, non-starter.
If I like something on NSF, it's probably because I know it to be accurate.  Every once in a while, it's just something I agree with.  Facts generally receive the former.

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 15391
    • Space Launch Report
  • Liked: 8565
  • Likes Given: 1356
Re: Ares I with lighter upper stage engines
« Reply #17 on: 10/27/2009 08:59 pm »
Non-starter.  The gravity losses from carrying RP1 instead of LH2 would be huge.
1) The original ATK inline concepts included a J-2S powered LH2 upper stage able to lift 16-18 tonnes to LEO and a kerosene upper stage loaded with 113 tonnes of propellant able to lift 13 tonnes to LEO, both on top of 4-segment boosters.

1) And look at how well the performance predictions of subsequent ATK inline concepts have turned out

Not bad, actually.  Subsequent studies showed that a four-segment booster topped by a J-2S powered second stage would have been able to lift *more* than 18 tonnes - as much as 20-ish tonnes - to the CEV insertion orbit. 

 - Ed Kyle

Offline Lobo

  • Senior Member
  • *****
  • Posts: 6915
  • Spokane, WA
  • Liked: 672
  • Likes Given: 437
Re: Ares I with lighter upper stage engines
« Reply #18 on: 10/27/2009 09:50 pm »
For it's stated mission (seems to be short on payload even for that), but I'm curious: What does 5seg + ACES-41 do? Or could it manage ACES-71? I'm not suggesting it's a good idea, just wondering.

It drops into the Ocean somewhere short of the European/African coastline because it doesn't have *close* to the necessary thrust required to get it into orbit from the point where that first stage places it (in velocity/altitude terms).

Also, ACES-41 is lighter, so the First Stage acceleration and Max-Q would get significantly worse too.

J-2X is actually underpowered for this configuration and in order to pick up correct acceleration levels after FS jettison, you would require 12 RL-10B-2's to match its thrust levels.

Ross.

Ross,

I’m curious about your statement here.  You said the 5-seg booster wouldn’t get it high enough, and the ACES-41 wouldn’t have enough thrust to get to LEO.  However, ULA is saying a regular Atlas V can launch them with either an Orion capsule, or their ACES/Altair ascent module and get them into LEO, although they’ll be empty when they get there and need a LEO depot.

I thought the 5-Seg SRB had more lifting capacity than the Atlas V 1st stage.  So why couldn’t an Ares 1/ACES-41 get Orion with an ACES-41 SM into LEO?

Seems like it would and have fuel to spare.  Obviously ULA is saying it’s ok to Launch the ACES-41 with less than a full fuel load or else the Atlas V couldn’t get off the ground. 
If Atlas V is supposed to be able to do it, why not the Ares 1 first stage?

(Not that I’m advocating Ares 1 here.  I’d much rather see a full ACES-41 SM with Orion Capsule go to LEO with enough fuel to get to TLI and not need the LEO depot).

Offline Antares

  • ABO^2
  • Senior Member
  • *****
  • Posts: 5181
  • Done arguing with amateurs
  • Liked: 371
  • Likes Given: 228
Re: Ares I with lighter upper stage engines
« Reply #19 on: 10/27/2009 09:56 pm »
1) And look at how well the performance predictions of subsequent ATK inline concepts have turned out
Not bad, actually.  Subsequent studies showed that a four-segment booster topped by a J-2S powered second stage would have been able to lift *more* than 18 tonnes - as much as 20-ish tonnes - to the CEV insertion orbit.

I really wish you had a badge, Ed, so we could dispense with these arguments.
If I like something on NSF, it's probably because I know it to be accurate.  Every once in a while, it's just something I agree with.  Facts generally receive the former.

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 15391
    • Space Launch Report
  • Liked: 8565
  • Likes Given: 1356
Re: Ares I with lighter upper stage engines
« Reply #20 on: 10/27/2009 11:37 pm »
1) And look at how well the performance predictions of subsequent ATK inline concepts have turned out
Not bad, actually.  Subsequent studies showed that a four-segment booster topped by a J-2S powered second stage would have been able to lift *more* than 18 tonnes - as much as 20-ish tonnes - to the CEV insertion orbit.

I really wish you had a badge, Ed, so we could dispense with these arguments.

I turned in my badge when I left for greener pastures years ago.  I still have a collection of mission specific site passes in a drawer (including one for 51-L that I didn't look at for years), as well as the temporary badge they gave me to get me to the exit gate! 

All I'm saying is that the original-original inline SRB-based launcher concept was not unreasonable.  It was modest actually, and safety driven.  And, guess what, it didn't even originate at ATK! 

 - Ed Kyle
« Last Edit: 10/28/2009 01:29 pm by edkyle99 »

Offline Lars_J

  • Senior Member
  • *****
  • Posts: 6160
  • California
  • Liked: 677
  • Likes Given: 195
Re: Ares I with lighter upper stage engines
« Reply #21 on: 10/27/2009 11:56 pm »
But even the original "stick" still had the SSME airstarted second stage, right? So while the concept may have looked simple back then, the whole 2nd stage should have seemed problematic from the beginning...

And speaking of that - How far along is the second stage of Ares I? How many years away is an Ares 1-Y launch, which I presume would have a 2nd stage?
« Last Edit: 10/27/2009 11:58 pm by Lars_J »

Offline the_roche_lobe

  • Member
  • Full Member
  • *
  • Posts: 100
  • Liked: 3
  • Likes Given: 0
Re: Ares I with lighter upper stage engines
« Reply #22 on: 10/28/2009 01:18 am »
In retrospect (always in retrospect), while making the SSME air RE-startable is clearly pretty much impossible, would it have been THAT hard to just make it one-off air startable? Expensive yes Im sure, but more expensive than all the subsequent 5 segment / J2-X teeth gnashing?

Lots of people here, including 'stick haters' seem to have at least grudgingly admitted that the original 4 seg / SSMME concept, while hardly elegant, was at least an acceptable kludge, especially if it was combined with a more sensible 'classic'/DIRECT sized HLV using the same main engines and SRBs.

Things seems to start getting seriously out of control the moment the SSME was removed from the Ares I equation.

P

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 37440
  • Cape Canaveral Spaceport
  • Liked: 21450
  • Likes Given: 428
Re: Ares I with lighter upper stage engines
« Reply #23 on: 10/28/2009 01:22 am »
Expensive yes Im sure, but more expensive than all the subsequent 5 segment / J2-X teeth gnashing?


J-2X would still be required.

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 15391
    • Space Launch Report
  • Liked: 8565
  • Likes Given: 1356
Re: Ares I with lighter upper stage engines
« Reply #24 on: 10/28/2009 03:54 am »
But even the original "stick" still had the SSME airstarted second stage, right? So while the concept may have looked simple back then, the whole 2nd stage should have seemed problematic from the beginning...

The first post-Columbia accident concept called for a J-2 or J-2S second stage engine.  There were earlier single-stick studies, performed by Lockheed during the 1990s, that considered SSME or J-2S powered stages atop an ASRM derived first stage.

The stage isn't problematic technically, it is more like a schedule hog due to the J-2X development timeline (combined with limited funding).  But Orion will probably be the final schedule driver.

Substantial J-2X testing can't begin until the big new A-3 test stand at Stennis is finished.  That probably won't be until late 2010 or 2011.  J-2X powerpack testing will be first up. 

Michoud production capacity buildup is supposed to occur in 2009-2010.  Build of the first Ares I upper stage ground test article at Michoud is supposed to occur in 2011-2012.  It will be tested at MSFC, probably in the dynamics tower, mostly during 2013.  Build of US-00 for Ares I-Y is supposed to occur in 2012-2013.   

 - Ed Kyle
« Last Edit: 10/28/2009 04:02 am by edkyle99 »

Offline gin455res

  • Full Member
  • ****
  • Posts: 510
  • bristol, uk
  • Liked: 42
  • Likes Given: 72
Re: Ares I with lighter upper stage engines
« Reply #25 on: 10/28/2009 12:12 pm »
I hope this isn't too naive a question but here goes:

Are there any parallel staged upperstages?

If something like the stick or direct is still suffering from considerable gravity losses on the second  stage, is there any reason why this couldn't be improved in the same way that boosters on parallel staged first stage help fight gravity losses and reduce the size of the sustainer engines.

Why isn't this technique also used for second-stages and upperstages?

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 15391
    • Space Launch Report
  • Liked: 8565
  • Likes Given: 1356
Re: Ares I with lighter upper stage engines
« Reply #26 on: 10/28/2009 01:10 pm »
I hope this isn't too naive a question but here goes:

Are there any parallel staged upperstages?

If something like the stick or direct is still suffering from considerable gravity losses on the second  stage, is there any reason why this couldn't be improved in the same way that boosters on parallel staged first stage help fight gravity losses and reduce the size of the sustainer engines.

Why isn't this technique also used for second-stages and upperstages?

Yes, there have been parallel, or cluster, upper stages.  The first U.S. satellite, Explorer 1, was boosted to orbit by a spinning cluster of relatively small solid rocket motors.

For a liquid upper stage, the easier approach would be to add another engine.  Alternative Crew Launch Vehicle designs with upper stages powered by two J-2S engines were studied during ESAS.  The designs allowed much more second stage propellant, which increased LEO payload by 2 to 4 tonnes.

 - Ed Kyle
« Last Edit: 10/28/2009 01:12 pm by edkyle99 »

Offline William Barton

  • Senior Member
  • *****
  • Posts: 3487
  • Liked: 8
  • Likes Given: 0
Re: Ares I with lighter upper stage engines
« Reply #27 on: 10/28/2009 01:33 pm »
I hope this isn't too naive a question but here goes:

Are there any parallel staged upperstages?

If something like the stick or direct is still suffering from considerable gravity losses on the second  stage, is there any reason why this couldn't be improved in the same way that boosters on parallel staged first stage help fight gravity losses and reduce the size of the sustainer engines.

Why isn't this technique also used for second-stages and upperstages?

Yes, there have been parallel, or cluster, upper stages.  The first U.S. satellite, Explorer 1, was boosted to orbit by a spinning cluster of relatively small solid rocket motors.

For a liquid upper stage, the easier approach would be to add another engine.  Alternative Crew Launch Vehicle designs with upper stages powered by two J-2S engines were studied during ESAS.  The designs allowed much more second stage propellant, which increased LEO payload by 2 to 4 tonnes.

 - Ed Kyle

I thought of mentioning Jupiter-C (a.k.a. Juno I), especially since the third stage was tucked inside the center of the second-stage cluster, but it begs the question whether that kind of sequential firing is any different from a conventional in-line serial stage concept. As far as I know, there haven't been an booster-sustainer upper stages in the exact sense of the way R-7 and Atlas I did things. Though I guess you could argue the case for Shuttle. The SSMEs don't fire again after MECO, but the OMS sometimes fires during ascent, and then again after MECO. Stretching the point...

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
0