Author Topic: Pad 39B to gain new Flame Deflector and Trench upgrade  (Read 26003 times)


Offline GClark

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #1 on: 02/06/2015 06:32 AM »
And a fine piece of journalism it is, sir.

I doff my hat in your general direction (I would hit your tip jar, if you had one).

Offline Martin FL

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #2 on: 02/06/2015 11:32 AM »
Really enjoy infrastructure articles! That was another great read.

And a fine piece of journalism it is, sir.

I doff my hat in your general direction (I would hit your tip jar, if you had one).


If you don't already have it, get L2! That's the site's tip jar, with massive benefits! :)

Offline spacenut

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #3 on: 02/06/2015 01:44 PM »
Will the new flame deflector take a higher pressure for future larger rockets?

Offline chrisking0997

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #4 on: 02/06/2015 05:24 PM »
Did I understand correctly that they are removing (some of) the brick from the trench or just the old flame deflector?
Tried to tell you, we did.  Listen, you did not.  Now, screwed we all are.

Offline Halidon

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #5 on: 02/06/2015 05:31 PM »
Thanks for the article, Chris. From an outsider's perspective, I would think that a flame deflector that can handle the heat/pressure from SLS could do the job for most smaller vehicles as well, provided they don't have an unusual configuration like STS. Would I be wrong in that assumption?

Offline AS_501

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #6 on: 02/06/2015 05:34 PM »
Did I understand correctly that they are removing (some of) the brick from the trench or just the old flame deflector?

If so, we can presume they will apply lessons learned after STS-124 blew out some of the bricks lining the trench.  Foot note:  Still hard to image any rocket engines generating as much blast force as five F-1s.

Offline Jim

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #7 on: 02/06/2015 05:52 PM »
Still hard to image any rocket engines generating as much blast force as five F-1s.

One 5 segment SRB is more than 2 F-1s and has a more blast force during ignition.  Much easier to build flame deflector for F-1s than SRB's

Offline PahTo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #8 on: 02/06/2015 07:44 PM »

To answer spacenut's and Halidon's queries, as well as follow-on to AS_501 and Jim, the trench and deflector is being fabricated to specs for "advanced boosters"--that is, fiber wound case (FWC) units that have even higher over-pressure than the 5-segs (which are much higher than even the "tuned up" 4-seg boosters used on STS-124).  It should be noted that the F-1s ramped up in thrust (and acoustical energy) over a number of seconds, while the SRBs exert a massive amount of OP at ignition (see transient overpressure vs MEOP [Mean Effective Operating Pressure]).
One of the coating materials used in lieu of the old bricks to withstand the OP and heat is "fondue fyre".  I can't imagine another rocket that will create the same sonic, thermal and OP as the notional FWC, or even the 5 segs, but we'll see (at least from 39B, a-hem).  Any other rocket that flies from 39B would only be constrained by orientation, not output.
I'm still of a mind the first launch of SLS (should it actually come to pass) will prove to be a learning experience re: pad substrate, structure and MLP/LUT.

Offline PahTo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #9 on: 02/06/2015 08:02 PM »

Oh, and sorry to double-post, but I am curious if they're going to "split" the SRB exhaust (one N and one S) or mimic the STS and have RS-25s flow S and both SRBs flow N (and thus under the MLP).  It would seem to make more sense to try to split evenly/distribute those forces, but those calculations Chris mentioned are critical to understanding flow patterns, waves that cancel and waves that amplify...
btw, thanks for the article on infrastructure, Chris!

Offline newpylong

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #10 on: 02/06/2015 08:08 PM »
Exhaust will not be split. All to the north.

Offline AS_501

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #11 on: 02/06/2015 08:13 PM »
Still hard to image any rocket engines generating as much blast force as five F-1s.

One 5 segment SRB is more than 2 F-1s and has a more blast force during ignition.  Much easier to build flame deflector for F-1s than SRB's

Interesting, thanks.  Do SRBs create a "sand-blasting" effect (from any un-burnt propellent?) on the trench that liquid engines do not?

Offline AS_501

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #12 on: 02/06/2015 08:41 PM »

To answer spacenut's and Halidon's queries, as well as follow-on to AS_501 and Jim, the trench and deflector is being fabricated to specs for "advanced boosters"--that is, fiber wound case (FWC) units that have even higher over-pressure than the 5-segs (which are much higher than even the "tuned up" 4-seg boosters used on STS-124).  It should be noted that the F-1s ramped up in thrust (and acoustical energy) over a number of seconds, while the SRBs exert a massive amount of OP at ignition (see transient overpressure vs MEOP [Mean Effective Operating Pressure]).
One of the coating materials used in lieu of the old bricks to withstand the OP and heat is "fondue fyre".  I can't imagine another rocket that will create the same sonic, thermal and OP as the notional FWC, or even the 5 segs, but we'll see (at least from 39B, a-hem).  Any other rocket that flies from 39B would only be constrained by orientation, not output.
I'm still of a mind the first launch of SLS (should it actually come to pass) will prove to be a learning experience re: pad substrate, structure and MLP/LUT.

Fascinating perspectives, thanks.  Probably a silly point here, but I wonder if there would be any value in staging some trench materials behind an SRB test motor in Utah, without compromising SRB test objectives.  Also, any indication if they will conduct an FRF on the first SLS?

Offline PahTo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #13 on: 02/08/2015 08:55 PM »
Fascinating perspectives, thanks.  Probably a silly point here, but I wonder if there would be any value in staging some trench materials behind an SRB test motor in Utah, without compromising SRB test objectives.  Also, any indication if they will conduct an FRF on the first SLS?

I know there are all kinds of evaluation hardware sensors all over the place, and beyond that, neighbors in the area have had direct experiences with erosive and corrosive by-products of motor firings (see threads covering DM testing); and I don't know, respectively.

Offline Jim

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #14 on: 02/08/2015 08:59 PM »


Interesting, thanks.  Do SRBs create a "sand-blasting" effect (from any un-burnt propellent?) on the trench that liquid engines do not?

Not just unburnt but the primary fuel is aluminum, so it is very corrosive.

Offline TomH

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #15 on: 02/09/2015 02:11 AM »
Not just unburnt but the primary fuel is aluminum, so it is very corrosive.

The advanced solid boosters will have greater pressure, but do we know enough yet about their formula to know whether they will be more/less corrosive, more/less toxic?

Offline Jim

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #16 on: 02/09/2015 02:56 AM »
That would be splitting hairs.

Offline MP99

That would be splitting hairs.
Chlorine can have that effect. :-)

Cheers, Martin

Offline Lobo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #18 on: 02/09/2015 09:54 PM »
Exhaust will not be split. All to the north.

Wasn't Saturn V's exhaust split?  I'd assume so as 39A and B were built with both north and south flame duts.  If so, why wouldn't SLS's be split too then?

Offline PahTo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #19 on: 02/09/2015 10:08 PM »
Exhaust will not be split. All to the north.

Wasn't Saturn V's exhaust split?  I'd assume so as 39A and B were built with both north and south flame duts.  If so, why wouldn't SLS's be split too then?

Note newlylong's response was re: SRB exhaust only per the context.  I expect the RS-25 exhaust will be directed S (same as it was for STS).  The geometry of the RS-25s might mean something different (a split of 2x2 N/S) but expect it to mimic STS.

Offline newpylong

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #20 on: 02/09/2015 11:21 PM »
No, all of the exhaust is going to the north, SRBs and RS-25s. No more wedge.
« Last Edit: 02/09/2015 11:21 PM by newpylong »

Offline Jim

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #21 on: 02/10/2015 12:05 AM »

Note newlylong's response was re: SRB exhaust only per the context.  I expect the RS-25 exhaust will be directed S (same as it was for STS).  The geometry of the RS-25s might mean something different (a split of 2x2 N/S) but expect it to mimic STS.

STS was split because of the sidemount

Offline PahTo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #22 on: 02/10/2015 01:56 PM »

Learn something new every day around this site...
Good stuff--thanks folks!

Offline AnalogMan

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #23 on: 02/10/2015 02:47 PM »
No, all of the exhaust is going to the north, SRBs and RS-25s. No more wedge.

There was some early evaluation of a flame deflector that diverted SRB and SSME plumes to different sides of the flame trench.  An idea labelled "Concept 1C2" was one of those and  incorporated a staggered ridge and slopes.

A simulation image of maximum surface pressures during SRB start-up shows the geometry considered - its compared to the baseline design which deflects to one side only.

Online DaveS

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #24 on: 02/10/2015 03:26 PM »

Note newlylong's response was re: SRB exhaust only per the context.  I expect the RS-25 exhaust will be directed S (same as it was for STS).  The geometry of the RS-25s might mean something different (a split of 2x2 N/S) but expect it to mimic STS.

STS was split because of the sidemount
To be accurate, Saturn V used wedge-shaped flame-deflector as well. It was mobile, on rails as it wasn't tied into the pad's water deluge system like the STS flame deflector.
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Offline PahTo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #25 on: 02/10/2015 03:38 PM »
Thanks for the images, AnalogMan.  I assume these are some of the products of the analysis (from article)

Quote
Following simulations using NASA Ames’ supercomputer, a deflector design – that could withstand the high heat from plume exhaust, that did not result in plume blow-back, and whose surface pressure was within design margin limits – was selected.

Offline Lobo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #26 on: 02/11/2015 04:02 PM »

Note newlylong's response was re: SRB exhaust only per the context.  I expect the RS-25 exhaust will be directed S (same as it was for STS).  The geometry of the RS-25s might mean something different (a split of 2x2 N/S) but expect it to mimic STS.

STS was split because of the sidemount
To be accurate, Saturn V used wedge-shaped flame-deflector as well. It was mobile, on rails as it wasn't tied into the pad's water deluge system like the STS flame deflector.

But was Saturn's flame divided?  It sure looks like it was in this picture.  And if so, why won't SLS's be divided?  It has all of it's exhaust in one central area like Saturn V, not offset like STS.  And it will be about 1Mlbs more thrust at liftoff that Saturn V  I'd always assumed 39A and 39B were set up the way they were because Saturn V had too much thrust to direct out just one flame port.  N-1's pad was built with 3 flame ducts...I assumed for the same reason. 
But if SLS's thrust can all go out the north side, seems like that was an incorrect assumption.  Why build the pad with two flame ducts then rather than just one if one can do the job?
« Last Edit: 02/11/2015 04:03 PM by Lobo »

Offline AS_501

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #27 on: 02/11/2015 04:28 PM »

Note newlylong's response was re: SRB exhaust only per the context.  I expect the RS-25 exhaust will be directed S (same as it was for STS).  The geometry of the RS-25s might mean something different (a split of 2x2 N/S) but expect it to mimic STS.

STS was split because of the sidemount
To be accurate, Saturn V used wedge-shaped flame-deflector as well. It was mobile, on rails as it wasn't tied into the pad's water deluge system like the STS flame deflector.

But was Saturn's flame divided?  It sure looks like it was in this picture.  And if so, why won't SLS's be divided?  It has all of it's exhaust in one central area like Saturn V, not offset like STS.  And it will be about 1Mlbs more thrust at liftoff that Saturn V  I'd always assumed 39A and 39B were set up the way they were because Saturn V had too much thrust to direct out just one flame port.  N-1's pad was built with 3 flame ducts...I assumed for the same reason. 
But if SLS's thrust can all go out the north side, seems like that was an incorrect assumption.  Why build the pad with two flame ducts then rather than just one if one can do the job?

I'm no engineer, but there is something inherently unsettling about deflecting all that energy in one direction (asymmetrically).  Perhaps this could damage the launch platform?

Offline newpylong

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #28 on: 02/11/2015 04:42 PM »
Stop the nonsense. Nothing is going to be damaged and there is nothing inherently bad with a unidirectional flame.

Simulations and testing to aid in design for things like this did not exist when Saturn and even STS were developed. The single trench is less complex, allows for easier inspection and will be cheaper to build.

Offline Jim

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #29 on: 02/11/2015 04:43 PM »

I'm no engineer, but there is something inherently unsettling about deflecting all that energy in one direction (asymmetrically).  Perhaps this could damage the launch platform?

No, see Atlas, Titan, Delta, etc

Offline Lobo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #30 on: 02/11/2015 05:02 PM »
Stop the nonsense. Nothing is going to be damaged and there is nothing inherently bad with a unidirectional flame.

Simulations and testing to aid in design for things like this did not exist when Saturn and even STS were developed. The single trench is less complex, allows for easier inspection and will be cheaper to build.

Yes, but we're talking a pad that's already built, not a new one they are going to build.  And the way it's built is to allow for exhaust out two sides especially with use of the Saturn type MLP's as SLS will.  Is it just today they are able to to in depth analysis of construction and determine that 39B was so over built that it can handle almost 9Mlbs of thrust out either side?  Something they'd couldn't be certain of in the 60's so they just added a lot of margin? Or something else?

I'm still trying to get the "why" of only using one side of an existing pad that already has two flame ports.  I understand the "why" of a new pad to only have one port with cost and simplicity.
« Last Edit: 02/11/2015 05:05 PM by Lobo »

Offline AS_501

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #31 on: 02/11/2015 05:03 PM »
Thanks all for the feedback.  While we're in the general area of the trench, it will be interesting to see how the SLS sound suppression water system will be configured, given that:
-  SLS will be generating more acoustic energy that STS (I assume)
-  The spacecraft is at the top of the stack and inside a shroud, not down on the side and exposed

Offline Jim

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #32 on: 02/11/2015 06:22 PM »
Thanks all for the feedback.  While we're in the general area of the trench, it will be interesting to see how the SLS sound suppression water system will be configured, given that:
-  SLS will be generating more acoustic energy that STS (I assume)
-  The spacecraft is at the top of the stack and inside a shroud, not down on the side and exposed


Also there is no large deck to reflect sound energy back at the vehicle

Much less of a requirement. 

Offline newpylong

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #33 on: 02/11/2015 06:51 PM »
Stop the nonsense. Nothing is going to be damaged and there is nothing inherently bad with a unidirectional flame.

Simulations and testing to aid in design for things like this did not exist when Saturn and even STS were developed. The single trench is less complex, allows for easier inspection and will be cheaper to build.

Yes, but we're talking a pad that's already built, not a new one they are going to build.  And the way it's built is to allow for exhaust out two sides especially with use of the Saturn type MLP's as SLS will.  Is it just today they are able to to in depth analysis of construction and determine that 39B was so over built that it can handle almost 9Mlbs of thrust out either side?  Something they'd couldn't be certain of in the 60's so they just added a lot of margin? Or something else?

I'm still trying to get the "why" of only using one side of an existing pad that already has two flame ports.  I understand the "why" of a new pad to only have one port with cost and simplicity.

I answered your questions already as to why. Just because there are two it doesn't mean you need to use both.

If you need further information I am sure it's out there direct from GSDO.

Offline Jim

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #34 on: 02/11/2015 07:04 PM »
Stop the nonsense. Nothing is going to be damaged and there is nothing inherently bad with a unidirectional flame.

Simulations and testing to aid in design for things like this did not exist when Saturn and even STS were developed. The single trench is less complex, allows for easier inspection and will be cheaper to build.

Yes, but we're talking a pad that's already built, not a new one they are going to build.  And the way it's built is to allow for exhaust out two sides especially with use of the Saturn type MLP's as SLS will.  Is it just today they are able to to in depth analysis of construction and determine that 39B was so over built that it can handle almost 9Mlbs of thrust out either side?  Something they'd couldn't be certain of in the 60's so they just added a lot of margin? Or something else?

I'm still trying to get the "why" of only using one side of an existing pad that already has two flame ports.  I understand the "why" of a new pad to only have one port with cost and simplicity.

I answered your questions already as to why. Just because there are two it doesn't mean you need to use both.

If you need further information I am sure it's out there direct from GSDO.

Having a single side flame deflector means that there is no leading edge that has to take the brunt of the exhaust.

Offline Lobo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #35 on: 02/11/2015 10:08 PM »
Stop the nonsense. Nothing is going to be damaged and there is nothing inherently bad with a unidirectional flame.

Simulations and testing to aid in design for things like this did not exist when Saturn and even STS were developed. The single trench is less complex, allows for easier inspection and will be cheaper to build.

Yes, but we're talking a pad that's already built, not a new one they are going to build.  And the way it's built is to allow for exhaust out two sides especially with use of the Saturn type MLP's as SLS will.  Is it just today they are able to to in depth analysis of construction and determine that 39B was so over built that it can handle almost 9Mlbs of thrust out either side?  Something they'd couldn't be certain of in the 60's so they just added a lot of margin? Or something else?

I'm still trying to get the "why" of only using one side of an existing pad that already has two flame ports.  I understand the "why" of a new pad to only have one port with cost and simplicity.

I answered your questions already as to why. Just because there are two it doesn't mean you need to use both.

If you need further information I am sure it's out there direct from GSDO.

Having a single side flame deflector means that there is no leading edge that has to take the brunt of the exhaust.

And that certainly makes sense as well.

Why did Saturn V divide it's thrust then rather than just have it all go out the north as well? 

Offline Lobo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #36 on: 02/11/2015 10:13 PM »
Stop the nonsense. Nothing is going to be damaged and there is nothing inherently bad with a unidirectional flame.

Simulations and testing to aid in design for things like this did not exist when Saturn and even STS were developed. The single trench is less complex, allows for easier inspection and will be cheaper to build.

Yes, but we're talking a pad that's already built, not a new one they are going to build.  And the way it's built is to allow for exhaust out two sides especially with use of the Saturn type MLP's as SLS will.  Is it just today they are able to to in depth analysis of construction and determine that 39B was so over built that it can handle almost 9Mlbs of thrust out either side?  Something they'd couldn't be certain of in the 60's so they just added a lot of margin? Or something else?

I'm still trying to get the "why" of only using one side of an existing pad that already has two flame ports.  I understand the "why" of a new pad to only have one port with cost and simplicity.

I answered your questions already as to why. Just because there are two it doesn't mean you need to use both.

If you need further information I am sure it's out there direct from GSDO.

Not exactly.  You said why a single ducted trench is better than a multi ducted one if they were building a new one.  "Cheaper to build" to quote you.  But not how that applies to an existing two ducted trench which doesn't need to be built.  And if it makes mores sense to use just one side of it even though it has two, why did Saturn use both?

I'm not arguing, just curious.  Trying to learn.  :-)

 

Offline catdlr

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #37 on: 02/12/2015 01:38 AM »
Stop the nonsense. Nothing is going to be damaged and there is nothing inherently bad with a unidirectional flame.

Simulations and testing to aid in design for things like this did not exist when Saturn and even STS were developed. The single trench is less complex, allows for easier inspection and will be cheaper to build.

Yes, but we're talking a pad that's already built, not a new one they are going to build.  And the way it's built is to allow for exhaust out two sides especially with use of the Saturn type MLP's as SLS will.  Is it just today they are able to to in depth analysis of construction and determine that 39B was so over built that it can handle almost 9Mlbs of thrust out either side?  Something they'd couldn't be certain of in the 60's so they just added a lot of margin? Or something else?

I'm still trying to get the "why" of only using one side of an existing pad that already has two flame ports.  I understand the "why" of a new pad to only have one port with cost and simplicity.

I answered your questions already as to why. Just because there are two it doesn't mean you need to use both.

If you need further information I am sure it's out there direct from GSDO.

Having a single side flame deflector means that there is no leading edge that has to take the brunt of the exhaust.

And that certainly makes sense as well.

Why did Saturn V divide it's thrust then rather than just have it all go out the north as well? 


Perhaps to reduce possible debris (blast force) raining down on the SpaceX horizontal integration assets just a 1/4 mile to the south of the pad?  Where as the Saturn and Shuttle facilities were 4 miles away.
« Last Edit: 02/12/2015 01:39 AM by catdlr »
Tony De La Rosa

Offline SWGlassPit

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #38 on: 02/13/2015 01:56 PM »
It's just shy of a mile south.  1/4 mile south is the pad perimeter fence.

Offline chrisking0997

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #39 on: 02/13/2015 04:39 PM »
debris from 39B flying to 39A?  :o
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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #40 on: 02/16/2015 05:05 PM »
I doubt that's it.  I'm guessing it's just with modern CAD anaysis and materials to construct a flame deflector today, that they're able to be pretty sure that all of SLS's thrust can be channelled out just one side of 39B's trench.  And if it can handle that, then it has some benefits as Jim and others have mentioned.  STS's offset engines needed for the thrust to be divided out both sides, and with Saturn, they designed it to withstand a Nova Class rocket, and just set Saturn V up the way a Nova would sit on the pad, with it's thrust divided out both sides.  There wasn't the sort of CAD analysis available in the 1960's so there was no reason not to just to error on the side of caution in case deflecting all of Saturn V's thrust out just the north side caused some sort of problems.

That's my guess, but I was hoping for someone who knew the real reason Saturn V was divided while SLS will not be, even thought Saturn V had less thrust than SLS will, could explain fully.

PS:  I wonder if it has anything to do with the "width" of the thrust?  SLS's width will only be around 8.4m wide, pretty much just the width of the core as the RS-25 nozzles won't prodrude very far from the core (at lease as depicted in renderings of SLS).  Saturn V's was a little over 11m as the F-1 nozzles were a little wider than the 10m S-1C.  Maybe 11+m wide meant deflecting it all out to one side would mean to shallow of a slope for a deflector.  So they actually had to divide it?  SLS's deflector is shorter and would have a steeper slope.  Perhaps steep enough to be provide enough thrust redirection?

Offline edkyle99

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #41 on: 02/16/2015 07:15 PM »
That's my guess, but I was hoping for someone who knew the real reason Saturn V was divided while SLS will not be, even thought Saturn V had less thrust than SLS will, could explain fully.
According to:
http://www.hq.nasa.gov/pao/History/SP-4204/ch11-7.html
a two-sided deflector was selected for LC 39 because that was what had been used at LC 34 and LC 37.

According to:
http://www.hq.nasa.gov/pao/History/SP-4204/ch2-4.html
a two-sided deflector was chosen for LC 34 because the four-sided deflector design previously used by ABMA/MSFC for Redstone and Jupiter would have created plumes that would have blocked views from the blockhouse.  This was an uncooled design.  Single-direction deflectors were used on Saturn test stands at MSFC and MTF, but they needed to be water-cooled and also required the pedestal to be taller, raising costs.

Presumably, flame trench science has advanced since the early 1960s, especially as it relates to the use of acoustic suppression deluge systems.

 - Ed Kyle
« Last Edit: 02/16/2015 07:22 PM by edkyle99 »

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #42 on: 02/17/2015 04:11 PM »
That's my guess, but I was hoping for someone who knew the real reason Saturn V was divided while SLS will not be, even thought Saturn V had less thrust than SLS will, could explain fully.
According to:
http://www.hq.nasa.gov/pao/History/SP-4204/ch11-7.html
a two-sided deflector was selected for LC 39 because that was what had been used at LC 34 and LC 37.

According to:
http://www.hq.nasa.gov/pao/History/SP-4204/ch2-4.html
a two-sided deflector was chosen for LC 34 because the four-sided deflector design previously used by ABMA/MSFC for Redstone and Jupiter would have created plumes that would have blocked views from the blockhouse.  This was an uncooled design.  Single-direction deflectors were used on Saturn test stands at MSFC and MTF, but they needed to be water-cooled and also required the pedestal to be taller, raising costs.

Presumably, flame trench science has advanced since the early 1960s, especially as it relates to the use of acoustic suppression deluge systems.

 - Ed Kyle

Ahhh...thanks Ed.  That's the info I was looking for.

Well, one thing about all of the exhaust going north, is the plume won't obstruct the view from the Causeway when SLS takes off.  :-)

As an aside, depending on the size of a SpaceX BFR, they could probably launch it from 39A basically how they will be launching Falcon, and direct all of the exhaust out the north side rather than needing to split it.  Which means the south side of the trench could contain the erecting mechanisms.

Offline jacqmans

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #43 on: 03/05/2016 08:48 AM »
Upgrades and modifications continue to the flame trench at Launch Pad 39B at NASA’s Kennedy Space Center in Florida. Pad B is being refurbished to support the launch of NASA’s Space Launch System rocket. The Ground Systems Development and Operations (GSDO) Program at Kennedy is helping transform the space center into a multi-user spaceport and prepare for Exploration Mission-1, deep-space missions, and the journey to Mars. For more information about GSDO, visit: www.nasa.gov/groundsystems. Photo credit: NASA/Kim Shiflett

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #44 on: 03/05/2016 01:27 PM »
Upgrades and modifications continue to the flame trench at Launch Pad 39B at NASA’s Kennedy Space Center in Florida. Pad B is being refurbished to support the launch of NASA’s Space Launch System rocket. The Ground Systems Development and Operations (GSDO) Program at Kennedy is helping transform the space center into a multi-user spaceport and prepare for Exploration Mission-1, deep-space missions, and the journey to Mars. For more information about GSDO, visit: www.nasa.gov/groundsystems. Photo credit: NASA/Kim Shiflett

Are there any commitments from other users to use LC-39B or any work being done on the infrastructure to accommodate other users?  Haven't heard a word on that topic for a couple years...
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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #45 on: 03/06/2016 12:00 AM »
Upgrades and modifications continue to the flame trench at Launch Pad 39B at NASA’s Kennedy Space Center in Florida. Pad B is being refurbished to support the launch of NASA’s Space Launch System rocket. The Ground Systems Development and Operations (GSDO) Program at Kennedy is helping transform the space center into a multi-user spaceport and prepare for Exploration Mission-1, deep-space missions, and the journey to Mars. For more information about GSDO, visit: www.nasa.gov/groundsystems. Photo credit: NASA/Kim Shiflett

There really is a remarkable amount of work that's gone on there. I have a picture from 39A that really contrasts from that last shot of 39B.

« Last Edit: 03/06/2016 12:06 AM by rayleighscatter »

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #46 on: 04/29/2016 07:08 PM »
Kennedy's Launch Pad 39B Transforms for Launch of Largest Rocket Ever

NASAKennedy

Published on Apr 29, 2016
In the Launch Pad 39B north flame trench at NASA’s Kennedy Space Center in Florida, construction workers prepare the concrete walls for new heat-resistant bricks. The Pad B flame trench is being refurbished to support the launch of NASA’s Space Launch System rocket. The Ground Systems Development and Operations Program at Kennedy is helping transform the space center into a multi-user spaceport and prepare for Exploration Mission 1, deep-space missions, and the journey to Mars. For more information about GSDO, visit: www.nasa.gov/groundsystems.

Video Location: https://www.youtube.com/results?search_query=RZ9j97zxWUo

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #49 on: 07/26/2017 06:17 AM »
At Launch Pad 39B at NASA's Kennedy Space Center in Florida, construction workers position large segments of the support hardware for a new flame deflector in the flame trench. The new flame deflector will be positioned about six feet south of the shuttle-era flame deflector’s position. During liftoff of NASA’s Space Launch System, the rocket’s flame and energy will be diverted to the north side of the flame trench. The north side of the deflector will be protected by a NASA standard coating. The south side of the deflector will not be slanted and will have no lining. The new design will provide easier access for inspection, maintenance and repair. The Ground Systems Development and Operations (GSDO) Program at Kennedy is managing the installation of the flame deflector for Exploration Mission 1, deep space missions, and NASA's Journey to Mars.
Photo credit: NASA/Kim Shiflett

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #50 on: 07/26/2017 06:18 AM »

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #51 on: 07/26/2017 06:19 AM »

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #52 on: 07/26/2017 06:21 AM »


Offline Lars-J

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #54 on: 07/26/2017 04:49 PM »
I thought they were done with the flame trench wall upgrades, but in the last image we see a closeup of the south end, which looks in pretty bad condition. (Wall cracks, weeds, etc) Are they only doing the northern end?

Offline Khadgars

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Re: Pad 39B to gain new Flame Deflector and Trench upgrade
« Reply #55 on: 07/26/2017 05:35 PM »
I thought they were done with the flame trench wall upgrades, but in the last image we see a closeup of the south end, which looks in pretty bad condition. (Wall cracks, weeds, etc) Are they only doing the northern end?

That is how I understand it.  The exhaust is being channeled in one direction only, the Flame Deflector you are seeing being erected in the pictures above will direct it towards the newly minted flame trench (just completed earlier this month).  The other side of the flame trench does not need to be upgraded.

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