From Atlas V to Falcon XX - Commercial suitors wanted for Pad 39A

[Lars_J]

Falcon v1.0 didn't really have any pad access I don't think, unless a guy could climb up the strongback in it's vertical position. 
Other than a crew access arm for a crewed LV, how much pad access would F9/FH need compared to STS?

For the COTS 1 mission, where they needed to shorten the MVac nozzle, a crane was used for access the interstage. (see image)

[Lobo]

So, would it be better to have a MSS that retracted off to the ramp side of the pad?  Or modify the RSS into a full enclsure?

From the picture below it looks liek there's be enough room on the ramp side of the pad to make an LC-37 like MSS on rails.  (assuming the CT isn't partially on the ramp...hard to tell for sure from that picture).
But that would require a lot of tearing up of the surface of the pad to install the rails and other things necessary.  But that might not be too hard.

But if they gutted the RSS, and build an enclosure on the rotating support elements, that could potentially be easier than a brand new MSS.  maybe...

Anyone have thoughts one which way would be better for them to go?  (speculation here of course).

Or perhaps they might go more like LC-41, and have a fixed VIB on the ramp side of the pad about where the Saturn V MSS is depicted in the above picture.  And then stack F9/FH on an Atlas V like MLP and integrate the payload in that.  Then the MLP slides out over the flame trench on some installed rails.  The STS RSS is removed entirely, and the FSS stripped down and an extention built on top (if necessary, it might not be depending on the height of the F9/FH MLP).  It would only serve as a crew access tower for manned launches and only have a crew access arm on top, with the crew escape slide wires moved up to that higher level.  Everything else would be taken care of in the similar way it's done now at LC-40, except the umbilical tower wouldn't need to got horizontal like the strongback, but be fixed vertical like the Atlas V UT.  It would be fixed to the MLP. 
That actually would be much closer to how SpaceX does it now.  But obviously the cores would be loaded into the VIB from the ramp side, rather than be moved in throught the flame trench on the other side as Jim proposed. 
They would be loaded into one side of the VIB onto the MLP and UT that would already be there.  And then the stack on the MLP with UT would roll out the other side to the [new modified] fixed crew access tower.
The flame divider would be removed and a flame wall installed so no plume comes out the ramp side of the pad.

Maybe that would be the more simple solution, and more in common with how SpaceX does it now?
Seems to work pretty good for Atlas V.  There's just be a much shorter rollout from the VIB to the pad and crew access tower.

[Lars_J]

I was wondering what the two set of tracks behind the 39A pad were for, but then I saw this image - apparently the flame deflector could be moved out there. My question is - Why? And was that still done for STS?

[Lobo]

For the COTS 1 mission, where they needed to shorten the MVac nozzle, a crane was used for access the interstage. (see image)

I suppose it wouldn't be an undesirable thing then if the Falcon stack were of a height where the STS intertank access arm and structure could be used then?  The LOX and RP-1 could be pumped into the upper stage and lower stage tanks from there too then I'd assume.  With new RP-1 pipes run right along with the existing LOX and LH2 lines.  Could be a good use of existing hardware then.

[Jim]

I suppose it wouldn't be an undesirable thing then if the Falcon stack were of a height where the STS intertank access arm and structure could be used then?  The LOX and RP-1 could be pumped into the upper stage and lower stage tanks from there too then I'd assume.  With new RP-1 pipes run right along with the existing LOX and LH2 lines.  Could be a good use of existing hardware then.

Boosters are always fueled from their base.  Makes things easier.

[Jim]

I was wondering what the two set of tracks behind the 39A pad were for, but then I saw this image - apparently the flame deflector could be moved out there. My question is - Why? And was that still done for STS?

The one in the picture is a spare. 
The shuttle was fixed.

[Lars_J]

I *think* the Falcon tanks are filled from the bottom - Most of the interstage ducts/wiring is for the upper stage. But someone else can correct me if I'm wrong.

[Lobo]

I was wondering what the two set of tracks behind the 39A pad were for, but then I saw this image - apparently the flame deflector could be moved out there. My question is - Why? And was that still done for STS?

Interesting.  That also begs a question I'd not considered before.  If those tracks are still usable (don't know if they are), could they be extended a bit, and have a fixed VIF there?  Around the corner so that it would be out of the way from any plume coming out the trench. 
Then stack F9/FH on an Atlas V like MLP and roll it around the bend into the trench.  The umbilicals could then come from the FSS and the MLP would be of such a height where it would line up correctly (otherwise they'd have to be brought down into the trench to the MLP base) and have enough from for the flame plume to go put the bottom out the flame trench rather than come directly back up.  It could even be deflected out the ramp side of the flame trench and not back out the trench side at all.  Saturn V and STS flame plumes come out both sides, after all.

Interesting...  There might be a few different ways to skin this cat.

[Jim]

I *think* the Falcon tanks are filled from the bottom - Most of the interstage ducts/wiring is for the upper stage. But someone else can correct me if I'm wrong.

Yes, but upperstage was from umbilical

[Lobo]

I suppose it wouldn't be an undesirable thing then if the Falcon stack were of a height where the STS intertank access arm and structure could be used then?  The LOX and RP-1 could be pumped into the upper stage and lower stage tanks from there too then I'd assume.  With new RP-1 pipes run right along with the existing LOX and LH2 lines.  Could be a good use of existing hardware then.

Boosters are always fueled from their base.  Makes things easier.

Thanks for the info.  Then if the F9 cores were loaded into the trench as you said, on a stand, how would they get the RP-1 and LOX down to the base?  Just bring it over the side and down or something?  Wouldn't you wnat the base of the boosters up on top of the trench then?

If you fueled the booster from the same umbilical (STS intertank access arm) as the upper stage, then you wouldn't need to run the lines down into the trench.
But maybe running them down into the trench would be a pretty easy thing...

[Jim]

But maybe running them down into the trench would be a pretty easy thing...

Don't need to go up the pad and down the trench, just come around on ground level into the trench.

[A_M_Swallow]

{snip}
If you fueled the booster from the same umbilical (STS intertank access arm) as the upper stage, then you wouldn't need to run the lines down into the trench.
But maybe running them down into the trench would be a pretty easy thing...

If they lines get burnt during takeoff classify them as expendable and ensure that they are easy to replace.

[Heinrich]

{snip}
If you fueled the booster from the same umbilical (STS intertank access arm) as the upper stage, then you wouldn't need to run the lines down into the trench.
But maybe running them down into the trench would be a pretty easy thing...

If they lines get burnt during takeoff classify them as expendable and ensure that they are easy to replace.

Be careful now. If the line gets damaged, you get loss of containment of RP1. Which will catch fire. Oil floats on water. Water from sound suppression system. So now you not only have a local pool fire, but a hydrocarbon fire floating on water which is draining towards... [ I don't know. Some catch basin a presume...]

With regards to filling from top: I would assume the reason for filling from the bottom is that you can use the same line for draining the tank upon a scrub.

[MP99]

I'd always assumed it was to avoid dropping prop from top of the tank, and forming bubbles in the liquid.

Cheers, Martin

[padrat]

@Lobo,
   With the Saturns, the RP-1 lines ran right beside the LH2 lines. The pedestals are wide enough.
I would think the current tank and lines would work just fine for methane. I don't know how heavy methane is compared to hydrogen, but I guess that it would depend on how high you need to push the methane as to if you would need to install pumps. Also the only real maintenance needed on the LH2 lines is maintaining the vacuums and a GN2 or GHe purge in the inner line to keep out air and moisture...

[Lobo]

@Lobo,
   With the Saturns, the RP-1 lines ran right beside the LH2 lines. The pedestals are wide enough.
I would think the current tank and lines would work just fine for methane. I don't know how heavy methane is compared to hydrogen, but I guess that it would depend on how high you need to push the methane as to if you would need to install pumps. Also the only real maintenance needed on the LH2 lines is maintaining the vacuums and a GN2 or GHe purge in the inner line to keep out air and moisture...

Padrat,

Thanks for all the great insight.

A few questions though.

1)  What are the chances you would be transferred over from LC-40 to LC-39A if SpaceX leases it?  You worked on both 39A and 39B for STS, correct?  Be ironic to be back there again?

2) What are the chances that a methane LV would launch from 39A if it were to be modified to fly F9R and FH?  What is the likely need to retain the LH2 systems to be utilized for CH4?  Not that it would hurt anything to just leave them just in case there was a future need, if they aren't in the way.  And it doesn't sound like they would be if new RP-1 lines can just be run righ where the old ones were.  But, just wondering if SpaceX would do a future renovation to launch a methane rocket, or if they'd do that from a different new pad once this one was flying F9R and FH?

3)  Do you have any educated speculation on how SpaceX might modify 39A for their needs?  Obviously we've been speculating, but do you have any more educated speculation of what we might expect?

[Occupymars]

http://www.spacenews.com/article/launch-report/36701blue-origin-wary-of-sharing-launch-pad-with-sls

[newpylong]

Despite their worries (which at a max flight rate of once a year for SLS are quite unwarranted) an overall best use of available facilities is Blue Origin on 39b, which NASA is rebuilding for shared use, and SpaceX on A. I hope this is how it goes down.

[Proponent]

Conops docs released thus far indicate that many SLS missions will require multiple launches, and that launches can't be less that 120 days apart.  In a year in which a multi-launch SLS mission took place, Blue Origin might be locked out of the pad for months.

[JBF]

A flight rate of one launch per year of SLS doesn't mean Blue Origin would be able to use the pad 364 days per year.

I think what BO is worried about is if SLS goes out to the pad and sits on it for weeks.