Could Ares 1 have Worked if things had been different?

[Downix]

How did they do it ?

http://www.thefreelibrary.com/ATK+Successfully+Conducts+Its+First-Ever+Start-Stop-Start+Solid...-a0131555528

Ok, so it's a pre-designed shutoff, not whereby you can shut off something already underway in case of emergency.

 It has a variable area nozzle (pintle nozzle) which they can control to reduce the internal pressure at any time in flight, and so terminate burn.

That would need to be a big nozzle to drop the pressure that much.

[renclod]

That would need to be a big nozzle to drop the pressure that much.

They did the experiment for Army tactical stuff, so... no too big, I'd guess.

[edkyle99]

Ed.... Say something....
Robert

O.K.  Consider this alternative.  We have to go back in time for this.  Back to 2005.  Have NASA develop the ESAS Crew Launch Vehicle with the RS-25 upper stage engine and the four segment booster.  Then use it.  Don't spend billions more for Ares V.  Fly lots of Ares I rockets, using the unparalleled scoot and shoot capability of LC 39 - the purpose for which it was originally designed, and go to the Moon using LEO rendezvous as Von Braun intended.  Use the Ares I upper stage as the basis for propellant depot and TLI stage. 

After the program is underway, if deemed helpful, NASA could go ahead and develop five-segment booster or liquid RP booster.  Either would push payload up to 35 or more tonnes to LEO. 

 - Ed Kyle

I can raise you one, and save a ton of money in the process. Don't develop Ares I at all and launch those payloads on EELV. When the need for more lift is there, peruse one of the evolution options.

Without Ares V, Ares I had no purpose for existing.

I agree with you for today - with the modification that I wouldn't limit it to just EELVs, but in 2005 the fiscal and political realities were different.  Imagine, had such a "one-rocket" approach been followed from the get-go.  Today the mass layoffs would not be quite as massive.  "Padrat" and friends would still be at work.  Ares I would have already performed a couple of test flights (since Ares I-X would have actually been an Ares I test - we're assuming a four-segment booster Ares I) and the upper stage engine would probably be further along than today's J-2X.  There might be an Ares I stacked in the VAB on that big new MLP right now.  The Orion coming to KSC next year wouldn't be flying on a Delta IV, it would be flying on a crew-rated Ares I.

 - Ed Kyle

[Jim]

Actually, it is true for today and 2005. There was never a need for Ares I.  In 2005, CEV was going fly in EELV and should have flown already.  The layoffs were inevitable.

There could have been addition pads for Atlas and Delta and billions left over for payloads,  both unmanned and for HSF.

[A_M_Swallow]

Can a SRB be airlit?

Definitely. But why?

You swap the design of the Ares 1 around.  The SSME is a stage 1 engine.  An airlit SRB gives you the stage 2.

There are a few flight path design problems such as changing where the stage 1 shuts down depending on the destination.  The stage 3, probably the SM, controls the final orbit.

[Oberon_Command]

Can a SRB be airlit?

Definitely. But why?

You swap the design of the Ares 1 around.  The SSME is a stage 1 engine.  An airlit SRB gives you the stage 2.

Why would you do that, though? I don't see what that buys you. The SRM is really big and heavy, and hydrogen has a low density, so you'd need a HUGE first stage and lots of SSMEs just to get the thing off the ground, never mind into orbit.

[Jorge]

Can a SRB be airlit?

Definitely. But why?

You swap the design of the Ares 1 around.  The SSME is a stage 1 engine.  An airlit SRB gives you the stage 2.

That's silly. The SRB is much better suited as a first stage due to its high thrust. It's poorly suited for a second stage due to its poor Isp.

[Jason1701]

Solids are the epitome of what you don't want in a second stage: high mass, low Isp, very high thrust, short burn time.

[ChileVerde]

Can a SRB be airlit?

Sure. There have been ICBMs dropped out of C-5s and biggish MDA target rockets out of C-17s. And, if you're looking for air-lit at high velocities, solid second stages of SLVs do it at as a matter of course. Whatever else you may think about them, solid rockets are relatively straightforward animals.

[ChileVerde]

Solids are the epitome of what you don't want in a second stage: high mass, low Isp, very high thrust, short burn time.

Which hasn't kept people from using them as second stages.  Cheap, compact and simple sometimes wins the game, other technical matters notwithstanding.

[baldusi]

Solids are the epitome of what you don't want in a second stage: high mass, low Isp, very high thrust, short burn time.

Which hasn't kept people from using them as second stages.  Cheap, compact and simple sometimes wins the game, other technical matters notwithstanding.

If I might reinforce the fundamental part: solids are cheap, at least on the marginal cost. That's why Orbital use them on the Taurus II (that and the fact that they needed 100% US made).

[edkyle99]

Actually, it is true for today and 2005. There was never a need for Ares I.  In 2005, CEV was going fly in EELV and should have flown already.  The layoffs were inevitable.

There could have been addition pads for Atlas and Delta and billions left over for payloads,  both unmanned and for HSF.

Perhaps, but time-traveling back to 2005, neither EELV then available could lift a lunar-mission Orion.  Ares I, especially an Ares I with an SSME upper stage, would have out-lifted 2005's Delta IV Heavy.   There was also the safety thing, which was a dominant force in the post-Columbia years.   

Yes, Ares I was costly, but the version postulated in this thread should have cost less than the version cancelled last year.  Meanwhile, EELV costs have skyrocketed, so that's also no picnic.

 - Ed Kyle

[Downix]

Actually, it is true for today and 2005. There was never a need for Ares I.  In 2005, CEV was going fly in EELV and should have flown already.  The layoffs were inevitable.

There could have been addition pads for Atlas and Delta and billions left over for payloads,  both unmanned and for HSF.

Perhaps, but time-traveling back to 2005, neither EELV then available could lift a lunar-mission Orion.  Ares I, especially an Ares I with an SSME upper stage, would have out-lifted 2005's Delta IV Heavy.   There was also the safety thing, which was a dominant force in the post-Columbia years.   

Yes, Ares I was costly, but the version postulated in this thread should have cost less than the version cancelled last year.  Meanwhile, EELV costs have skyrocketed, so that's also no picnic.

 - Ed Kyle

You're making stuff up Ed.  ESAS agreed that the EELV's could lift a lunar mission Orion.  It did list that Ares I could outlift the Delta IV, by a half ton, but also that the Atlas V HLV could outlift the Ares I.  They sold Ares I based on inflated safety numbers, not in lift demands.

[edkyle99]

Actually, it is true for today and 2005. There was never a need for Ares I.  In 2005, CEV was going fly in EELV and should have flown already.  The layoffs were inevitable.

There could have been addition pads for Atlas and Delta and billions left over for payloads,  both unmanned and for HSF.

Perhaps, but time-traveling back to 2005, neither EELV then available could lift a lunar-mission Orion.  Ares I, especially an Ares I with an SSME upper stage, would have out-lifted 2005's Delta IV Heavy.   There was also the safety thing, which was a dominant force in the post-Columbia years.   

Yes, Ares I was costly, but the version postulated in this thread should have cost less than the version cancelled last year.  Meanwhile, EELV costs have skyrocketed, so that's also no picnic.

 - Ed Kyle

You're making stuff up Ed.  ESAS agreed that the EELV's could lift a lunar mission Orion.  It did list that Ares I could outlift the Delta IV, by a half ton, but also that the Atlas V HLV could outlift the Ares I.  They sold Ares I based on inflated safety numbers, not in lift demands.

ESAS proper described EELV rockets that didn't exist.  The Delta IV Heavy had a "new upper stage".  Atlas V Heavy of course still doesn't exist, but even the version in ESAS had a "new upper stage" (not Centaur).

Infamous Appendix 6 showed Ares I (the SSME version) out lifting the base EELV Heavies (including the Atlas V Heavy) by nearly a tonne gross, given that NASA wouldn't have used the RL10B-2 on a crew launcher.

 - Ed Kyle

[Downix]

Actually, it is true for today and 2005. There was never a need for Ares I.  In 2005, CEV was going fly in EELV and should have flown already.  The layoffs were inevitable.

There could have been addition pads for Atlas and Delta and billions left over for payloads,  both unmanned and for HSF.

Perhaps, but time-traveling back to 2005, neither EELV then available could lift a lunar-mission Orion.  Ares I, especially an Ares I with an SSME upper stage, would have out-lifted 2005's Delta IV Heavy.   There was also the safety thing, which was a dominant force in the post-Columbia years.   

Yes, Ares I was costly, but the version postulated in this thread should have cost less than the version cancelled last year.  Meanwhile, EELV costs have skyrocketed, so that's also no picnic.

 - Ed Kyle

You're making stuff up Ed.  ESAS agreed that the EELV's could lift a lunar mission Orion.  It did list that Ares I could outlift the Delta IV, by a half ton, but also that the Atlas V HLV could outlift the Ares I.  They sold Ares I based on inflated safety numbers, not in lift demands.

ESAS proper described EELV rockets that didn't exist.  The Delta IV Heavy had a "new upper stage".  Atlas V Heavy of course still doesn't exist, but even the version in ESAS had a "new upper stage" (not Centaur).

Infamous Appendix 6 showed Ares I (the SSME version) out lifting the base EELV Heavies (including the Atlas V Heavy) by nearly a tonne gross, given that NASA wouldn't have used the RL10B-2 on a crew launcher.

 - Ed Kyle

*sigh* Ed, I point you to LV3, a baseline Delta IV with regular upper stage. And the ESAS report itself underreported the DIVH's performance by a full tonne, according to the DIVH Payload Planners Guide. The performance compared to the Ares I, well, I'll let you see for yourself, not a tonne difference at the standard 28.5 degree inclination:

[edkyle99]

*sigh* Ed, I point you to LV3, a baseline Delta IV with regular upper stage. And the ESAS report itself underreported the DIVH's performance by a full tonne, according to the DIVH Payload Planners Guide. The performance compared to the Ares I, well, I'll let you see for yourself, not a tonne difference at the standard 28.5 degree inclination:

That is LV 3.1, not a stock Delta IV Heavy (that was LV 3.0), but a version with a different upper stage engine (the RL10B-2 second stage engine replaced with an RL10A-4-2).  This version also used modified RS-68 engines.

The reason for the payload differences were two-fold.  First, the planners guides give information for unmanned launches flown on highly lofted trajectories.  Crewed flights would follow flatter trajectories, giving up some payload capacity in the process.  Second, the planners guides give data for payloads enclosed in relatively lightweight fairings rather than for spacecraft topped by much heavier launch abort systems.

As I said, I agree that existing or soon to exist launch vehicles could support a lunar landing program.  Here, we're discussing a "what if" about 2005 and a 4-segment booster/SSME upper stage inline Shuttle Derived crew launch vehicle.  Politically, in 2005, I believe that Shuttle-Derived was a winner compared to EELVs.  We're still seeing that today with SLS.  I'm not saying that I agree with the politics, just that it exists.  The all-existing rocket to the moon program that I would prefer does not exist, has not been seriously proposed, and as near as I can tell will never happen.

 - Ed Kyle 

[yinzer]

Agreed that Shuttle-derived rockets are politically preferable to EELVs, but they don't seem preferable enough to actually get built.

Assuming the switch to 5-segment/J-2X hadn't happened, the Ares I and ISS Orion could probably be flying today.  I suspect the operational costs would have grown to the point that there'd be nothing left for developing Ares V or going to the moon, but we might have gotten a cargo Orion out of it.

[strangequark]

You swap the design of the Ares 1 around.  The SSME is a stage 1 engine.  An airlit SRB gives you the stage 2.

There are a few flight path design problems such as changing where the stage 1 shuts down depending on the destination.  The stage 3, probably the SM, controls the final orbit.

You'd need 6 SSMEs to do it, aside from all the other problems. Complete non-starter that adds way more problems than it fixes.

[A_M_Swallow]

You swap the design of the Ares 1 around.  The SSME is a stage 1 engine.  An airlit SRB gives you the stage 2.

There are a few flight path design problems such as changing where the stage 1 shuts down depending on the destination.  The stage 3, probably the SM, controls the final orbit.

You'd need 6 SSMEs to do it, aside from all the other problems. Complete non-starter that adds way more problems than it fixes.

I did not say that it was cheap.

[Patchouli]

Ares I probably could have worked if they were willing to do a lot of unmanned flight testing and accept that a few will end up in the Atlantic during development.

But Ares I should have fell under the ax when the air started SSME did not work out as it was the SSME's performance that made it work as a a Delta IV-H class LV.

The 1.5 launch architecture also put far too many requirements on the CaLV Ares V.
If they switched to Jupiter and a 2 launch architecture when the air started SSME fell through they'd be flight testing hardware already.

Another fix they could have went with a kerolox first stage on Ares I using the nearly finished TR-107 engine pretty much reinventing Jarvis.
This would have gave them upwards of a 38,000kg payload giving the Orion design team much needed breathing room.
One of biggest delays was the move from a 5.5M OML to a 5M one.
It also should be powerful enough to allow testing of the LSAM in LEO.
Fuel would have to be off loaded or Altair would have to perform part of the orbital injection.