Senate Commerce Committee Executive and Congress Version - July 15 onwards

[simonbp]

Today Shuttle C or Not Shuttle C have no advantages over an inline vehicle, and have a lot of serious drawbacks.

I wouldn't say none, as the JSC Sidemount does get away with not having to replace/modify a lot of systems at KSC and MAF, and so could be ready sooner for cheaper initial costs. Its disadvantages come into play in the longer term, with flexibility and recurring costs.

[clongton]

Today Shuttle C or Not Shuttle C have no advantages over an inline vehicle, and have a lot of serious drawbacks.

I wouldn't say none, as the JSC Sidemount does get away with not having to replace/modify a lot of systems at KSC and MAF, and so could be ready sooner for cheaper initial costs. Its disadvantages come into play in the longer term, with flexibility and recurring costs.

Not so. They still need to build that side mount pod which EVERYONE SEEMS TO FORGET (or ignore) is not just an empty can mounted on the side. It's a brand new space shuttle orbiter minus the tiles and wings. It's a huge bloody rocket all by itself with propulsion and avionics all it's own. It's expensive as all hell.

[Jorge]

Today Shuttle C or Not Shuttle C have no advantages over an inline vehicle, and have a lot of serious drawbacks.

I wouldn't say none, as the JSC Sidemount does get away with not having to replace/modify a lot of systems at KSC and MAF, and so could be ready sooner for cheaper initial costs. Its disadvantages come into play in the longer term, with flexibility and recurring costs.

Not so. They still need to build that side mount pod which EVERYONE SEEMS TO FORGET (or ignore) is not just an empty can mounted on the side. It's a brand new space shuttle orbiter minus the tiles and wings. It's a huge bloody rocket all by itself with propulsion and avionics all it's own. It's expensive as all hell.

It's important not to *overstate* it either. The *current* sidemount concept remains attached to the ET and does not go into orbit with the payload, so it is not as complex as a Shuttle-C type of design would have been. In particular, the current sidemount needs *no* additional avionics above what inline needs, nor does it need propulsion other than the SSMEs (which are also needed for inline). This means the payload needs propulsion, but that is the case regardless.

[Namechange User]

Nor does sidemount have OMS/RCS, fuel cells and PRSD tanks, ET disconnects, etc.  It is about as close to an "empty can" as you can get, I mean heck, half of jetisons off during ascent.

[simonbp]

Not so. They still need to build that side mount pod which EVERYONE SEEMS TO FORGET (or ignore) is not just an empty can mounted on the side. It's a brand new space shuttle orbiter minus the tiles and wings. It's a huge bloody rocket all by itself with propulsion and avionics all it's own. It's expensive as all hell.

Chuck, one would think that you hadn't actually read the JSC HLV study on L2. The current sidemount design (first presented publicly over a year ago) is no more complex than an equal-sized inline design.

And I'm not drinking the Kool-Aid that inline is going to be cheap on the infrastructure. The point is that it's cleaner-sheet, and that's going to extend to KSC and MAF...

[Ben the Space Brit]

Today Shuttle C or Not Shuttle C have no advantages over an inline vehicle, and have a lot of serious drawbacks.

I wouldn't say none, as the JSC Sidemount does get away with not having to replace/modify a lot of systems at KSC and MAF, and so could be ready sooner for cheaper initial costs.

How much of this infrastructure is really re-used?

It is my understanding that Ares-I-X pretty much trashed Pad 39B's FSS, which had been partially disassembled anyway to fit I-X on it.  The high bays in the VAB would need to be modified as the work platforms would need to be re-shaped for the Side-mount cargo pod, which is wider than the shuttle orbiter.  It is also my understanding that both the pads at LC-39 will need a degree of refurbishment because of the damage caused by SRM exhaust products over the past 30 years and that the MLPs may also need replacement too, no matter what vehicle is chosen.

IMHO, Side-Mount will require as many infrastructure changes & refurbishment as In-line, just different ones.  It is unlikely that they will necessarily turn out The question is more about what kind of vehicle you want.  All the data I've seen suggests that In-line is more adaptable and has higher payload limits than Side-Mount.

@simonbp,

JSC's study is disadvantaged by proposing a completely artificial three-stage evolution (Side-Mount, Hybrid, In-line) that requires the development of three different engine boat-tails, at least one extra redesign of the ET and at least one extra refurbishiment of the VAB high bays.  I've got a feeling that going direct to In-line would cost a lot less and provide a lot more capability and far more quickly.

[edit]
Just to emphasise, my understanding of the JSC study is that they agreed that In-line in some form would eventually be necessary.  Wouldn't it be better to save money and go directly there? An in-line SLS-Medium (J-130) would have the same capabilities as the Side-Mount and be quickly evolvable into the SLS-Heavy (J-246/-241) without costly extra infrastructure and vehicle redesigns.

The JSC Three-Stage HLV evolution is in many ways repeating the key conceptual failing of the published form of ESAS - the fallacy that NASA can afford to develop and field multiple heavy launcher types over a very tight time-frame.

Now it becomes political - are certain individuals willing to have an HLV if it doesn't look like an evolved shuttle to the untutored eye?

[Integrator]

Why are we still discussing sidemount here? It is time to face reality and move forward.  No amount of wishful thinking or evangelizing will ever bring it back folks.  The decision has been made.  Let's move on.

INTEGRATOR

[MP99]

JSC's study is disadvantaged by proposing a completely artificial three-stage evolution (Side-Mount, Hybrid, In-line) that requires the development of three different engine boat-tails, at least one extra redesign of the ET and at least one extra refurbishiment of the VAB high bays.  I've got a feeling that going direct to In-line would cost a lot less and provide a lot more capability and far more quickly.

That wasn't the recommended way forward, just one way to end up with in-line.

cheers, Martin

[JohnFornaro]

They still need to build that side mount pod which EVERYONE SEEMS TO FORGET (or ignore) is not just an empty can mounted on the side.

Except for me?

This is largely why I believe that the partially finished tanks that we already have should be used on the shuttle.  They are already fashioned for this exact purpose.

That the shuttle looks like a rig is because of the circumstances surrounding the decisions at the time of design.  Fine.  It's time to move on.  The assymetrical design, is fraught with unnecessary complications in this day and age, I'd say.  That "The *current* sidemount concept remains attached to the ET and does not go into orbit with the payload" is a small advantage for unmanned cargo flights only, IMO.

If Ben is right, there are no substantial infrastructure benefits either.  Clearly, limitations on payload diameter and length are less critical with in-line.  There is also the design time and cost necessary for the "three stage evolution" that Ben alludes to.  It may be, in some extremely narrow interpretation of optimization, that side-mount will come in a day sooner and a dollar cheaper than in-line.  The other thing going on is that ultimately, we want an in-line vehicle and really are wasting time and money considering the side-mount alternative in any more exhausting detail.

The things I've read so far are so fraught with exceptions and seemingly carefully constructed exclusions, that it is beyond my capabilities to justify my opinion.  Like the shock waves from the sidemount LAS?

I think that the most important part of the term "shuttle derived" is tank diameter.  From that Report on S3729:

Section 203. Assurance of core capabilities.
This section would provide a sense of Congress that existing space capabilities such as the ISS and Space Shuttle, and initial capabilities of follow-on transportation systems should be utilized to provide operational experience, technology development, and the requisite infrastructure for expanded future exploration missions.
This section also would require the Administrator to refurbish the ET-94 Space Shuttle external tank as a means of retaining necessary skills and capabilities in the fabrication and preparation for
flight readiness of large-diameter vehicle components necessary for development of the new Space Launch System.

Stick the damn thing in-line and let's move on.  [If I may be allowed to be one of 'us'.]

[robertross]

Why are we still discussing sidemount here? It is time to face reality and move forward.  No amount of wishful thinking or evangelizing will ever bring it back folks.  The decision has been made.  Let's move on.

INTEGRATOR

You make that sound as if it is already off the table...but is it?

Unless you're making that a conclusive statement of fact? (hopefully)

[simonbp]

IMHO, Side-Mount will require as many infrastructure changes & refurbishment as In-line, just different ones.

I wouldn't go that far; JSC's assertion that Sidemount would require almost no changes is an exaggeration, but Sidemount would definitely require less. If nothing else, Inline needs a taller launch tower than the FSS, and some way of keeping it from falling over during rollout. While Sidemount, on the other hand, could use existing MLPs and at least the 39A FSS/RSS.

The question is more about what kind of vehicle you want.  All the data I've seen suggests that In-line is more adaptable and has higher payload limits than Side-Mount.

Oh, I'm not going to argue that Inline isn't a better design in the long term. The question is, is NASA confident that it can be flying crews on Inline by the end of 2016, or will they choose the slightly schedule-safer Sidemount? (The inline-payload, sidemount-boattail design in the report may have been an attempted answer to that question.)

[JohnFornaro]

...or will they choose the slightly schedule-safer Sidemount?

I'm just not convinced of the accuracy of, well, any of the schedule estimates.  Where does it say that either scheme will be finished by such and such a date?

[chrisking0997]

If nothing else, Inline needs a taller launch tower than the FSS, and some way of keeping it from falling over during rollout. While Sidemount, on the other hand, could use existing MLPs and at least the 39A FSS/RSS.

huh?  why would inline have a risk of "falling over during rollout"?

[TrueBlueWitt]

If nothing else, Inline needs a taller launch tower than the FSS, and some way of keeping it from falling over during rollout. While Sidemount, on the other hand, could use existing MLPs and at least the 39A FSS/RSS.

huh?  why would inline have a risk of "falling over during rollout"?

Good question..  seeing as the 300ft plus Ares-1X model rocket made it to.the pad supported by just a single SSRM.. and much lower bending preload for in-line design than shuttle or side-mount.

[spacetraveler]

And let's not forget we have a NASA administrator who's against Shuttle and SD HLV, and who's not been seen since the Muslim outreach scandal.

At a time NASA needs a leader, we've got a political yes man.

I'm not sure what the point of this post was.

Griffin supported Constellation, because that's what Bush wanted.

Bolden supports commercial because that's what Obama wants.

It is the job of the NASA administrator to support the president's space policy. If he did not the president would not have appointed him.

[kraisee]

HQ have weighed-in:   JSC has been instructed to support In-Line and to drop Sidemount.   Also, MSFC will remain the lead LV Development Center and JSC will remain the lead Orion Development Center and the Mission Operations Center.

After months and months of pointless in-fighting, this debate is finally over and the lines are finally set in stone.

Amazingly enough (or should that be predictably enough?) the lines all remain exactly the way they were before.

I can't help but think what a total waste of time and effort this stupid turf-war turned out to be.

I sure hope that both groups now knuckle-down and get on with the real job which they have ahead of them:   Making this new system work, on-time and on-budget.   Just how quickly the two factions can put this aside and really start pulling TOGETHER will, IMHO, become the clearest indication of whether NASA can be successful in this.

Ross.

[e of pi]

HQ have weighed-in:   JSC has been instructed to support In-Line and to drop Sidemount.   Also, MSFC will remain the lead LV Development Center and JSC will remain the lead Orion Development Center and the Mission Operations Center.

After months and months of pointless in-fighting, this debate is finally over and the lines are finally set in stone.

Amazingly enough (or should that be predictably enough?) the lines all remain exactly the way they were before.

I can't help but think what a total waste of time and effort this stupid turf-war turned out to be.

I sure hope that both groups now knuckle-down and get on with the real job which they have ahead of them:   Making this new system work, on-time and on-budget.   Just how quickly the two factions can put this aside and really start pulling TOGETHER will, IMHO, become the clearest indication of whether NASA can be successful in this.

Ross.

If side mount is truly dead, I think all turf wars in the meantime are now irrelevant. I do agree that I hope this means that both groups can now get to work on putting NASA back on track.

[MP99]

The JSC HLLV document pushed ULA-based upper stages.

Obviously, I don't know where MSFC's thinking on this lies, but that could still be a significant difference between the two centres..

cheers, Martin

[Ben the Space Brit]

The JSC HLLV document pushed ULA-based upper stages.

Obviously, I don't know where MSFC's thinking on this lies, but that could still be a significant difference between the two centres..

The MSFC D-SDLV study ('Ares-IV Redux' as I think of it) is where the re-purposing of the AIUS as an EDS comes from.  JSC, as you say, uses ACES heritage designs and Boeing's HLV paper uses something not unlike the AVUS.  DIRECT's proposals is essentially for a super-sized ACES (the JUS and ACES having a common ancestry in the Common Upper Stage concept) and, in that, they could be considered a hybrid of the Boeing and JSC proposals.

Fortunately, the 2016 deadline is for the SLS-M launching Orion to the ISS, not any BEO objective.  Instead of using five years to develop an HLV, will those years be used deciding which EDS to use?

[clongton]

DIRECT's proposals is essentially for a super-sized ACES

No so Ben; it's the other way around. The JUS came long before ACES. Therefore ULA's proposal is actually for a downsized JUS.