Author Topic: 6 segment SRB?  (Read 17537 times)

Offline nathansr

  • Member
  • Posts: 15
  • Liked: 0
  • Likes Given: 0
6 segment SRB?
« on: 04/04/2007 09:01 PM »
Would a 6 segment srb solve the Ares I's mass-to-orbit problems (assuming that the problem is with the Ares I rather than the Orion - which isn't necessarily the case!)? What are the issues here? Obviously this hasn't been tested at all whilst a 5 segment version has. The vehicle may be too tall & thus unstable.

Even if the 6 segment SRB does nothing for Ares I would it be useful for Ares V? Or would stability issues be a problem here too?

Just thinking out loud.

Offline AntiKev

  • Veteran
  • Full Member
  • *
  • Posts: 179
  • Pilot
  • Windsor, Ontario
    • James
  • Liked: 0
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #1 on: 04/04/2007 09:18 PM »
The biggest problem is that the SRBs weren't originally designed with this concept in mind.  Sure in principle you can add another middle section to the booster and change the propellant grain a little bit, but in practice it doesn't work that way.  The studies by Dr. Von Braun in the Apollo era show that using a solid first stage is sometimes a better option than using a liquid first stage.  Reference his Saturn I designs with 260-inch diameter solid first stages.  But I think that using shuttle technology as a design constraint here is the wrong way to go.  I am on the fence about the DIRECT proposal itself, but I favour that and an EELV launched Orion to the NASA-designed Ares I/V architecture.  There are some strange decisions and decrees that have come out of NASA management that have little basis in fact and have more to do with emotion.  The one that comes to mind being the no crew with cargo decree.

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10483
  • Liked: 415
  • Likes Given: 19
RE: 6 segment SRB?
« Reply #2 on: 04/04/2007 09:53 PM »
Quote
nathansr - 4/4/2007  5:01 PM

Would a 6 segment srb solve the Ares I's mass-to-orbit problems (assuming that the problem is with the Ares I rather than the Orion - which isn't necessarily the case!)? What are the issues here? Obviously this hasn't been tested at all whilst a 5 segment version has. The vehicle may be too tall & thus unstable.

Even if the 6 segment SRB does nothing for Ares I would it be useful for Ares V? Or would stability issues be a problem here too?

Just thinking out loud.

There are, unfortunately, a number of problems with the concept.   As it is, the fifth segment is already making the Stick very tall and ungainly and has caused problems which have had to be resolved.   Adding another segment would exacerbate this considerably.   One concern is the height - such a tall vehicle might perhaps even make the LV too tall to fit in the VAB!

Also the bending moments on the joins between the segments during flight are also considerable.   A sixth segment would create yet another join where the vehicle can bend during flight - this puts a lot of stress on the bolts holding the vehicle together - a 6th seg would probably over-stress some of these - especially on such a tall and thin structure.

Another concern would be that the pressure inside the SRB of all that propellant burning would increase internal pressures to a point where the existing cases may just not be able to handle the forces.   Perhaps this could be solved by using the PBAN propellant.   This would seem to offer a way to reduce the internal pressure while increasing the burn time.

And any big changes like this would always necessitate a complete re-design of the engine nozzle, TVC system and recovery parachutes.

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

Offline meiza

  • Expert
  • Senior Member
  • *****
  • Posts: 3068
  • Where Be Dragons
  • Liked: 3
  • Likes Given: 3
Re: 6 segment SRB?
« Reply #3 on: 04/04/2007 11:58 PM »
If the pressure was held the same and more thrust used, the throat&nozzle at the bottom would have to be widened but I understand they're as wide with the 5 seg booster as they can get without having to change the surrounding structures, which would cost a lot more because it requires new manufacture.

Offline Christine

  • Member
  • Posts: 79
  • Liked: 0
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #4 on: 04/05/2007 12:21 AM »
It would be a hell of a lot easier to simply widen the casings.

Offline HarryM

  • Member
  • Full Member
  • ****
  • Posts: 420
  • California
  • Liked: 25
  • Likes Given: 34
Re: 6 segment SRB?
« Reply #5 on: 04/05/2007 08:39 PM »
(From other posts) the tooling to make the casings is gone. The Ares-1 would be using casings recycled from STS (while they last), so not easy to change the size.

Seems the upper stage is the problem, no? (not easy to make airstartable SSME. Whoever the genius(s) were that said "sure, we can do that no problem" needs to be taken out and horsewhipped.) Since 2 J-2S will no fit in the upper stage would 2 smaller vernier engines fit to give it enough extra thrust, so 1 J-2S plus 2 RL-10 class engines?

Offline Scotty

  • Member
  • Full Member
  • ****
  • Posts: 1124
  • Merritt Island, Florida
  • Liked: 663
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #6 on: 04/05/2007 09:19 PM »
If the SRB was made larger than the current 148 inch in diameter, you could not move them via the rail system.
Then how would you get them to and from Utah?

The rail road was the limiting factor in the maximum diameter of the SRB.
There were plans for 156 inch diameter solids at the beginning of the Shuttle program, but when the predecessor of ATK won the contract, that idea went out the window for good.
A 18 foot diameter (216 inch) solid would be ideal for Ares I.
Anyone have 50 or so of them in storage at your house?

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10483
  • Liked: 415
  • Likes Given: 19
Re: 6 segment SRB?
« Reply #7 on: 04/05/2007 09:34 PM »
Scotty, I'm sure I've got a couple of 'em laying under my desk here...   Ahhh, nope.   The cat musta taken 'em... ;)

Seriously though, what ever happened to the really large casing for the Apollo Saturn-1B Solid First Stage which was being developed by P&W down near West Palm Beach?   It was something like 260" diameter IIRC.   I guess it got scrapped?

Even more seriously, is there another way to move large dangerous objects to and from Utah?   I don't know the territory there at all, but are there any rivers flowing within 100 miles of ATK's plant, which run to the sea?   That might allow barges to be used instead of rail cars, and then you might have the option to increase the diameter.   Of course, if we could take Utah out of the loop altogether...   But that's never going to happen because that state has way too much pull for this program.

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

Offline simonbp

Re: 6 segment SRB?
« Reply #8 on: 04/05/2007 09:49 PM »
The 260-inch/6.6m first stage solid that Aerojet developed for the Saturn I were monolithic, and so had to be cast on site. It would be nice for Ares I, though, if you could get the cost/politics to work...

http://www.astronautix.com/stages/260lidhl.htm

http://www.astronautix.com/lvs/satint05.htm

It was, incidentally, the largest rocket of any kind ever fired; must have been quite a sight/sound!

Simon :)

Offline meiza

  • Expert
  • Senior Member
  • *****
  • Posts: 3068
  • Where Be Dragons
  • Liked: 3
  • Likes Given: 3
Re: 6 segment SRB?
« Reply #9 on: 04/05/2007 11:31 PM »
They found out that storing big monolithic solids was hard - it'd sag, bend and crack and all that, so it had to be stored inclined and constantly rotated slowly...
Generic username said that the humid florida air was bad for casting the solids, and that was one of the reasons why ATK got the segmented solid deal. dunno then... The Aerojet facility is currently abandoned, somebody here posted about someone who went to take pics from it.

Offline yinzer

  • Extreme Veteran
  • Full Member
  • ****
  • Posts: 1509
  • Liked: 1
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #10 on: 04/06/2007 12:13 AM »
Quote
kraisee - 5/4/2007  2:34 PM

Even more seriously, is there another way to move large dangerous objects to and from Utah?   I don't know the territory there at all, but are there any rivers flowing within 100 miles of ATK's plant, which run to the sea?   That might allow barges to be used instead of rail cars, and then you might have the option to increase the diameter.   Of course, if we could take Utah out of the loop altogether...   But that's never going to happen because that state has way too much pull for this program.

Regarding rivers and Utah: no.  Surprisingly emphatically no.
California 2008 - taking rights from people and giving rights to chickens.

Online wannamoonbase

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 3084
  • Denver, CO
    • U.S. Metric Association
  • Liked: 747
  • Likes Given: 1206
Re: 6 segment SRB?
« Reply #11 on: 04/06/2007 12:38 AM »
Quote
Scotty - 5/4/2007  5:19 PM

If the SRB was made larger than the current 148 inch in diameter, you could not move them via the rail system.
Then how would you get them to and from Utah?

The rail road was the limiting factor in the maximum diameter of the SRB.
There were plans for 156 inch diameter solids at the beginning of the Shuttle program, but when the predecessor of ATK won the contract, that idea went out the window for good.
A 18 foot diameter (216 inch) solid would be ideal for Ares I.
Anyone have 50 or so of them in storage at your house?

Nutz to Utah is my answer to that.  Build them near water, that shouldn't be too hard to find in the US.  But keeping the work in Utah is the point of reusing the SRB isn't it?  (at least in some theories.)

I really like the idea of a shorter fatter SRB.  And you can't tell me that with all the money and time being spent on Ares 1 that tooling for the casings is a limiting factor.  It was built once it can be built again and probably better and more efficient now.

I don't buy the tooling arguments when you consider all the costs in these programs.  If you were doing it each time you built a vehicle perhaps, but not on a long term program such as this.
Needing a copy of 'Tales of Suspense #39'

Offline CFE

  • Extreme Veteran
  • Full Member
  • ****
  • Posts: 722
  • Liked: 1
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #12 on: 04/06/2007 01:47 AM »
I also agree that if we absolutely have to build Ares I, we should widen the SRB instead of lengthening it.  Is there a way to airlift the motor segments from the ATK plant in Utah, in the same way that Atlas V is airlifted from the plant in Colorado?  If not, the Aerojet plant in Florida should be renovated.  Perhaps ULA could modify the Decatur, AL plant to produce wider solid rockets.  Of course, the letter two ideas threaten to break ATK's stranglehold on the SRB business, and NASA would never stand for that.

Somebody had mentioned Von Braun and the Saturn INT-05 concept.  I don't know who at MSFC was behind that, as Von Braun was a vocal opponent of using solid rockets in manned spacecraft.  I share Von Braun's concerns, but I'd pick an INT-05 over an Ares I in a heartbeat.
"Black Zones" never stopped NASA from flying the shuttle.

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32440
  • Cape Canaveral Spaceport
  • Liked: 11186
  • Likes Given: 331
Re: 6 segment SRB?
« Reply #13 on: 04/06/2007 01:58 AM »
Quote
wannamoonbase - 5/4/2007  8:38 PM
 And you can't tell me that with all the money and time being spent on Ares 1 that tooling for the casings is a limiting factor.  It was built once it can be built again and probably better and more efficient now.

I don't buy the tooling arguments when you consider all the costs in these programs.  If you were doing it each time you built a vehicle perhaps, but not on a long term program such as this.

I am telling you and you must buy it.

1.  The company is out of business
2.  It is not just the tooling that is gone, but also the heat treatment facilities
3.  All the money is being used to qualify just a modified SRM, not a whole new design from ground zero

Just as battleship metal is made anymore

Also there is no efficency improvements.  The same processes would be involved.  If the same ones weren't involved, then more money to qualify the new processes

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32440
  • Cape Canaveral Spaceport
  • Liked: 11186
  • Likes Given: 331
Re: 6 segment SRB?
« Reply #14 on: 04/06/2007 02:05 AM »
Quote
CFE - 5/4/2007  9:47 PM

1. Is there a way to airlift the motor segments from the ATK plant in Utah, in the same way that Atlas V is airlifted from the plant in Colorado?  

2 If not, the Aerojet plant in Florida should be renovated.  
.

1 too big

2,  Not there any more

Offline jimvela

  • Member
  • Full Member
  • ****
  • Posts: 1307
  • Liked: 205
  • Likes Given: 10
Re: 6 segment SRB?
« Reply #15 on: 04/06/2007 02:09 AM »
Quote
yinzer - 5/4/2007  6:13 PM

Quote
kraisee - 5/4/2007  2:34 PM

Even more seriously, is there another way to move large dangerous objects to and from Utah?   I don't know the territory there at all, but are there any rivers flowing within 100 miles of ATK's plant, which run to the sea?   That might allow barges to be used instead of rail cars, and then you might have the option to increase the diameter.   Of course, if we could take Utah out of the loop altogether...   But that's never going to happen because that state has way too much pull for this program.

Regarding rivers and Utah: no.  Surprisingly emphatically no.

The Colorado river:

a)  has to pass through the Glen Canyon dam (Lake Powell, woo hoo!)
b)  has to pass through the Hoover Dam (Lake Mead)
c)  has to pass through a host of little diversion dams
d)  supplies drinking water and irrigation water to large parts of the southwestern US
e)  Thus trickles out before ever reaching baja, which would be a terrible route to ship things even if the river did still make it.


Offline EE Scott

  • Full Member
  • ****
  • Posts: 1153
  • Liked: 41
  • Likes Given: 138
RE: 6 segment SRB?
« Reply #16 on: 04/07/2007 07:35 PM »
Solids, solids, solids.  I wonder how large Aerojet could super-size the SRB they build for the Atlas V, while still keeping it monolithic and with its relatively lightweight filament-wound case design.  Three or four of those in parallel might be an alternative.  Nah, never happen.

Perhaps using 3 three-segment SRBs in parallel could work, but I gues the burn time would be way too short.  Or 3 three-segment SRBs around a center three segment SRB that would be air-started after stage 0 burned out.  How many design rules/safety factors can I violate at one time???  One could go crazy trying to design something decent with the stupid and arbitrary design constraints (e.g., shutle srbs for first stage) NASA has given itself for political purposes.  Hopefully NASA can make it work, otherwise we all get to watch VSE die a slow and painful death.
Scott

Offline aftercolumbia

  • Member
  • Full Member
  • **
  • Posts: 265
  • Liked: 0
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #17 on: 04/13/2007 05:49 PM »
Quote
Scotty - 5/4/2007  3:19 PM

If the SRB was made larger than the current 148 inch in diameter, you could not move them via the rail system.
Then how would you get them to and from Utah?

The rail road was the limiting factor in the maximum diameter of the SRB.
There were plans for 156 inch diameter solids at the beginning of the Shuttle program, but when the predecessor of ATK won the contract, that idea went out the window for good.
A 18 foot diameter (216 inch) solid would be ideal for Ares I.
Anyone have 50 or so of them in storage at your house?

Yeah, I got a couple six-packs in the basement, but FedEx says they won't fit in the van. ;)

Offline johng

  • Johnny Space Commander
  • Full Member
  • **
  • Posts: 263
  • Deland, FL
  • Liked: 2
  • Likes Given: 2
Re: 6 segment SRB?
« Reply #18 on: 08/07/2007 10:05 PM »
Quote
Jim - 5/4/2007  9:58 PM



I am telling you and you must buy it.

1.  The company is out of business
2.  It is not just the tooling that is gone, but also the heat treatment facilities
3.  All the money is being used to qualify just a modified SRM, not a whole new design from ground zero

Just as battleship metal is made anymore

Also there is no efficency improvements.  The same processes would be involved.  If the same ones weren't involved, then more money to qualify the new processes

I've was told, by someone involved, that the heat treat plant is there, it's just been mothballed and the experience base (workers) are gone. Anyhow, he didn't sound like new segments were that far out of the realm of possibility.

Anybody know exactly where the old Ginormous Aerojet Everglades facility was? I looked on Google maps and found the "Aerojet Canal" but could not identify a firing pit or blockhouse.

Offline Lee Jay

  • Elite Veteran
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6683
  • Liked: 982
  • Likes Given: 140
Re: 6 segment SRB?
« Reply #19 on: 08/07/2007 10:43 PM »
We recently did a logistics study on moving wind turbine tower sections so I have some data about this.

Rail is indeed limited to 4 meters overall height, which means about 3.7 meters in diameter.

Trucks can go to about 4.8 meters overall height which means around 4.4 meters in diameter.  Hey, send them by truck, you say!

Well...rail is limited to around 160mT, while trucks are limited to around 102mT.  I think the current segments are already too heavy to meet that 102mT requirement for the overall system, so making them bigger would necessitate making them shorter.  That means even more field joints.

There are exceptions to the weight limit, and I think the largest load ever moved over a major US highway was around 600mT (to Utah, an autoclave for a gold mine).  But that's a one-time thing that you can get permits for.  Doing something regularly is entirely different from the point of view of getting permits.

Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.  Did you know there are *several* off-shore cranes that can lift an entire STS stack, with fuel in the ET, and the MLP, quite easily?  Yikes!

Offline gladiator1332

  • Mike Majeski
  • Senior Member
  • *****
  • Posts: 2430
  • Fort Myers, FL
  • Liked: 4
  • Likes Given: 5
RE: 6 segment SRB?
« Reply #20 on: 08/08/2007 03:52 AM »
Here is what a 6 seg Ares I would look like in comparison to the current 5 seg:


Offline MKremer

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 3909
  • Liked: 13
  • Likes Given: 487
RE: 6 segment SRB?
« Reply #21 on: 08/08/2007 04:06 AM »
Quote
gladiator1332 - 7/8/2007  10:52 PM

Here is what a 6 seg Ares I would look like in comparison to the current 5 seg:


Change the nickname to "The Syringe".

Offline gladiator1332

  • Mike Majeski
  • Senior Member
  • *****
  • Posts: 2430
  • Fort Myers, FL
  • Liked: 4
  • Likes Given: 5
RE: 6 segment SRB?
« Reply #22 on: 08/08/2007 04:30 AM »
Quote
MKremer - 7/8/2007  12:06 AM

Quote
gladiator1332 - 7/8/2007  10:52 PM

Here is what a 6 seg Ares I would look like in comparison to the current 5 seg:


Change the nickname to "The Syringe".

I always thought the 5 seg looked out of proportion...but when you put it next to The Syringe, it looks quite nice.

Personally, I think we need a new nickname for the Stick. Look at the Ares I Evolution thread, ever since the CEV diameter went to 5.0m, Ares I has looked more like a German Potato Masher grenade.

Offline the_roche_lobe

  • Member
  • Full Member
  • *
  • Posts: 100
  • Liked: 2
  • Likes Given: 0
RE: 6 segment SRB?
« Reply #23 on: 08/08/2007 12:28 PM »
Just out of interest only, is PBAN the highest ISP solid compound around? Has any reasonable solid compound broken the '300 barrier', and if so what was the 'magic ingredient'? (I'm not for a moment suggesting that this would be a practical and cost effective way to boost the performance of the existing SRB BTW)

P

Offline BogoMIPS

  • Veteran
  • Full Member
  • **
  • Posts: 271
  • Liked: 0
  • Likes Given: 0
RE: 6 segment SRB?
« Reply #24 on: 08/08/2007 12:51 PM »
If we really get to the point that a 6th SRB segment is needed (which I don't think would happen), I think Stumpy (2x3 segment SRBs) is more likely.

If more performance is needed from the Stick at this point, and 1 5 Seg SRB and 1 J-2 derivative isn't going to cut it, I would expect to see a change in the upperstage to account for it now... Either a wider u/s with 2 J-2 derivatives, or a different upperstage engine all together.

Either that, or Orion will continue to downsize to match the Stick's performance.

Offline gladiator1332

  • Mike Majeski
  • Senior Member
  • *****
  • Posts: 2430
  • Fort Myers, FL
  • Liked: 4
  • Likes Given: 5
RE: 6 segment SRB?
« Reply #25 on: 08/08/2007 04:41 PM »
Another render to include a 260in solid first stage

Offline kevin-rf

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8652
  • Overlooking the path Mary's little Lamb took..
  • Liked: 1124
  • Likes Given: 243
Re: 6 segment SRB?
« Reply #26 on: 08/08/2007 05:26 PM »
uummm wasn't the aerojet 260 solid a monolithic solid and not a segmened solid?

So what is the throw weight of that baby... Anyone know how long it would need to be to meet the orion mass goals?
If you're happy and you know it,
It's your med's!

Offline Steve G

  • Regular
  • Full Member
  • *
  • Posts: 185
  • Edmonton, AB
    • Stephen H Garrity
  • Liked: 80
  • Likes Given: 5
Re: 6 segment SRB?
« Reply #27 on: 08/08/2007 05:50 PM »
For the sake of continuing the 260 solid discussion, assume they build the plant at KSC or near water.  What would the performance be for the Ares 1-260, and also, the Ares V-260?.  Also, what kind of weight would we be looking at?  I doubt if the crawlers could handle it.  lastly, in this day and age, what kind of danger would all these solids pose if there was a fire or terrorist attack?  That thought screamed at me when 9-11 was taking place.  What if they flew into the VAB?

Offline henrycheck

  • Member
  • Member
  • Posts: 84
  • Liked: 0
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #28 on: 08/08/2007 06:26 PM »
Quote
Steve G - 8/8/2007  1:50 PM

For the sake of continuing the 260 solid discussion, assume they build the plant at KSC or near water.  What would the performance be for the Ares 1-260, and also, the Ares V-260?.  Also, what kind of weight would we be looking at?  I doubt if the crawlers could handle it.  lastly, in this day and age, what kind of danger would all these solids pose if there was a fire or terrorist attack?  That thought screamed at me when 9-11 was taking place.  What if they flew into the VAB?

Why would the weight be different? Might even be lighter as the shape would be more efficient.

Explosive potential might be less as well since the exposed area would be smaller.

Quick calculation . . .

To have the same volume as a five-segment SRB, a 260-inch diameter motor would need to be about 60 feet high.

(3.14)[(148/2)^2](185)(12) = 38,000,000 cubic inches

(3.14)[(260/2)^2](h)(12) = 640,000h cubic inches

h = 60 feet


Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32440
  • Cape Canaveral Spaceport
  • Liked: 11186
  • Likes Given: 331
Re: 6 segment SRB?
« Reply #29 on: 08/08/2007 06:29 PM »
Why all the talk about 260?   The stick doesn't just use the SRB's because they are solid.  They are used because there is flight history.   A liquid stage would be used before the 260 since there is some flight history since the stage would use existing engines

Offline henrycheck

  • Member
  • Member
  • Posts: 84
  • Liked: 0
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #30 on: 08/08/2007 06:36 PM »
Quote
Jim - 8/8/2007  2:29 PM

Why all the talk about 260?   The stick doesn't just use the SRB's because they are solid.  They are used because there is flight history.   A liquid stage would be used before the 260 since there is some flight history since the stage would use existing engines


Continued use of solids might placate our friends in Utah.

Offline kfsorensen

  • aerospace and nuclear engineer
  • Full Member
  • ****
  • Posts: 1550
  • Huntsville, AL
    • Flibe Energy
  • Liked: 117
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #31 on: 08/08/2007 06:43 PM »
Quote
henrycheck - 8/8/2007  1:36 PM

Continued use of solids might placate our friends in Utah.
Yeah, with their vast political power....

Offline EE Scott

  • Full Member
  • ****
  • Posts: 1153
  • Liked: 41
  • Likes Given: 138
Re: 6 segment SRB?
« Reply #32 on: 08/08/2007 06:48 PM »
I doubt that ATK would be contracted to build a recreation of an Aerojet design.  Although the way decisions seem to get made currently, one must never say never...
Scott

Offline William Graham

  • Senior Member
  • *****
  • Posts: 4209
  • Liked: 213
  • Likes Given: 90
Re: 6 segment SRB?
« Reply #33 on: 08/08/2007 06:53 PM »
Quote
Lee Jay - 7/8/2007  11:43 PM
Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.

Super Guppy?

Offline henrycheck

  • Member
  • Member
  • Posts: 84
  • Liked: 0
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #34 on: 08/08/2007 07:00 PM »
Quote
EE Scott - 8/8/2007  2:48 PM

I doubt that ATK would be contracted to build a recreation of an Aerojet design.  Although the way decisions seem to get made currently, one must never say never...


If you wanted to build big solids, why not ATK? Mix the propellant in Utah, ship by train, cast in Florida.

Offline Lee Jay

  • Elite Veteran
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6683
  • Liked: 982
  • Likes Given: 140
Re: 6 segment SRB?
« Reply #35 on: 08/08/2007 07:10 PM »
Quote
GW_Simulations - 8/8/2007  12:53 PM

Quote
Lee Jay - 7/8/2007  11:43 PM
Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.

Super Guppy?

WAY too heavy.  Antonov 225, maybe.

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32440
  • Cape Canaveral Spaceport
  • Liked: 11186
  • Likes Given: 331
Re: 6 segment SRB?
« Reply #36 on: 08/08/2007 07:12 PM »
Quote
henrycheck - 8/8/2007  3:00 PM

Quote
EE Scott - 8/8/2007  2:48 PM

I doubt that ATK would be contracted to build a recreation of an Aerojet design.  Although the way decisions seem to get made currently, one must never say never...


If you wanted to build big solids, why not ATK? Mix the propellant in Utah, ship by train, cast in Florida.

The propellant has to be cast so after it is mixed

Offline William Graham

  • Senior Member
  • *****
  • Posts: 4209
  • Liked: 213
  • Likes Given: 90
Re: 6 segment SRB?
« Reply #37 on: 08/08/2007 07:12 PM »
Quote
Lee Jay - 8/8/2007  8:10 PM

Quote
GW_Simulations - 8/8/2007  12:53 PM

Quote
Lee Jay - 7/8/2007  11:43 PM
Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.

Super Guppy?

WAY too heavy.  Antonov 225, maybe.

How about the 747LCA?

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32440
  • Cape Canaveral Spaceport
  • Liked: 11186
  • Likes Given: 331
Re: 6 segment SRB?
« Reply #38 on: 08/08/2007 07:12 PM »
Quote
Lee Jay - 8/8/2007  3:10 PM

Quote
GW_Simulations - 8/8/2007  12:53 PM

Quote
Lee Jay - 7/8/2007  11:43 PM
Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.

Super Guppy?

WAY too heavy.  Antonov 225, maybe.

Still too heavy

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 32440
  • Cape Canaveral Spaceport
  • Liked: 11186
  • Likes Given: 331
Re: 6 segment SRB?
« Reply #39 on: 08/08/2007 07:12 PM »
Quote
Lee Jay - 8/8/2007  3:10 PM

Quote
GW_Simulations - 8/8/2007  12:53 PM

Quote
Lee Jay - 7/8/2007  11:43 PM
Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.

Super Guppy?

WAY too heavy.  Antonov 225, maybe.

Still too heavy

Offline kraisee

  • Expert
  • Senior Member
  • *****
  • Posts: 10483
  • Liked: 415
  • Likes Given: 19
Re: 6 segment SRB?
« Reply #40 on: 08/08/2007 07:30 PM »
Each SRB segment tips the scales right around 150mT when coming back from Utah to KSC ready for flight.

A C-5 "Galaxy" couldn't transport a single SRB segment.

An Antonov-124 could *just* move one at a time.

An Antonov-225 is still only capable of moving one SRB segment at a time.

Train is reasonably economical right now, but any larger would probably require a barge infrastructure of some sorts, and that means Utah would be a bad location.   If you were going to move the ATK plant somewhere else to enable barges, at that point, rather than build another facility and barge everything in, it probably would be more sensible to just relocate the facility to KSC's back yard.

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

Offline Lee Jay

  • Elite Veteran
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6683
  • Liked: 982
  • Likes Given: 140
Re: 6 segment SRB?
« Reply #41 on: 08/08/2007 07:42 PM »
Quote
Jim - 8/8/2007  1:12 PM

Quote
Lee Jay - 8/8/2007  3:10 PM

Quote
GW_Simulations - 8/8/2007  12:53 PM

Quote
Lee Jay - 7/8/2007  11:43 PM
Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.

Super Guppy?

WAY too heavy.  Antonov 225, maybe.

Still too heavy

That would depend on how much bigger than the current segments.  The thing can supposedly carry 250 metric tons.

Still - totally impractical for the intended purpose.

Offline meiza

  • Expert
  • Senior Member
  • *****
  • Posts: 3068
  • Where Be Dragons
  • Liked: 3
  • Likes Given: 3
Re: 6 segment SRB?
« Reply #42 on: 08/08/2007 07:45 PM »
As Generic Username said, the moist air in Florida is bad for the segment casting. Aerojet had the facility there, I don't know if they had any problems with that particular thing. The monolithic solids were so huge that they would sag if left lying and had to be held at an angle and rotated continuosly.

Online pippin

  • Regular
  • Senior Member
  • *****
  • Posts: 2565
  • Liked: 291
  • Likes Given: 39
Re: 6 segment SRB?
« Reply #43 on: 08/08/2007 08:01 PM »
Quote
Lee Jay - 8/8/2007  12:43 AM

We recently did a logistics study on moving wind turbine tower sections so I have some data about this.

Rail is indeed limited to 4 meters overall height, which means about 3.7 meters in diameter.

Trucks can go to about 4.8 meters overall height which means around 4.4 meters in diameter.  Hey, send them by truck, you say!

Well...rail is limited to around 160mT, while trucks are limited to around 102mT.  I think the current segments are already too heavy to meet that 102mT requirement for the overall system, so making them bigger would necessitate making them shorter.  That means even more field joints.

There are exceptions to the weight limit, and I think the largest load ever moved over a major US highway was around 600mT (to Utah, an autoclave for a gold mine).  But that's a one-time thing that you can get permits for.  Doing something regularly is entirely different from the point of view of getting permits.

Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.  Did you know there are *several* off-shore cranes that can lift an entire STS stack, with fuel in the ET, and the MLP, quite easily?  Yikes!

Well, well,...
You know, a few years ago we had this startup company here in Germany, called Cargolifter. They wanted to carry 600mT payloads by Blimp. I think what remains of them could be bought quite cheaply... They used to have a H U G E (as in REALLY H U G E) hanger which is now a tropical resort...

Offline Lee Jay

  • Elite Veteran
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6683
  • Liked: 982
  • Likes Given: 140
Re: 6 segment SRB?
« Reply #44 on: 08/08/2007 08:09 PM »
Quote
pippin - 8/8/2007  2:01 PM

Quote
Lee Jay - 8/8/2007  12:43 AM

We recently did a logistics study on moving wind turbine tower sections so I have some data about this.

Rail is indeed limited to 4 meters overall height, which means about 3.7 meters in diameter.

Trucks can go to about 4.8 meters overall height which means around 4.4 meters in diameter.  Hey, send them by truck, you say!

Well...rail is limited to around 160mT, while trucks are limited to around 102mT.  I think the current segments are already too heavy to meet that 102mT requirement for the overall system, so making them bigger would necessitate making them shorter.  That means even more field joints.

There are exceptions to the weight limit, and I think the largest load ever moved over a major US highway was around 600mT (to Utah, an autoclave for a gold mine).  But that's a one-time thing that you can get permits for.  Doing something regularly is entirely different from the point of view of getting permits.

Bottom line, if you want to move something in the US that's both larger in diameter and heavier than the current SRB segments, you have to do it over water where the limits are, well, insanely large.  Did you know there are *several* off-shore cranes that can lift an entire STS stack, with fuel in the ET, and the MLP, quite easily?  Yikes!

Well, well,...
You know, a few years ago we had this startup company here in Germany, called Cargolifter. They wanted to carry 600mT payloads by Blimp. I think what remains of them could be bought quite cheaply... They used to have a H U G E (as in REALLY H U G E) hanger which is now a tropical resort...

Yep...we looked into them in some detail.  There are some issues with that approach but some advantages as well.

Offline henrycheck

  • Member
  • Member
  • Posts: 84
  • Liked: 0
  • Likes Given: 0
Re: 6 segment SRB?
« Reply #45 on: 08/08/2007 08:09 PM »
Quote
Jim - 8/8/2007  3:12 PM

Quote
henrycheck - 8/8/2007  3:00 PM

Quote
EE Scott - 8/8/2007  2:48 PM

I doubt that ATK would be contracted to build a recreation of an Aerojet design.  Although the way decisions seem to get made currently, one must never say never...


If you wanted to build big solids, why not ATK? Mix the propellant in Utah, ship by train, cast in Florida.

The propellant has to be cast so after it is mixed


Quote
meiza - 8/8/2007  3:45 PM

As Generic Username said, the moist air in Florida is bad for the segment casting. Aerojet had the facility there, I don't know if they had any problems with that particular thing. The monolithic solids were so huge that they would sag if left lying and had to be held at an angle and rotated continuosly.

If we’re going to Mars we’ll need to overcome some hurdles.

At my condominium in Boca Raton I have a wonderful device called an “air conditioner.”

If you were to cluster three of these puppies you’d have a pretty good Ares V.

There are two showstoppers for me:

(1) Vibration - Haven’t seen this discussed but how smooth will the ride be for Orion sitting way up on one elongated SRB?

(2) Acceleration - Can the burn surface be shaped to control the burn rate. Otherwise, acceleration gets pretty nasty near propellant exhaustion.


Online pippin

  • Regular
  • Senior Member
  • *****
  • Posts: 2565
  • Liked: 291
  • Likes Given: 39
Re: 6 segment SRB?
« Reply #46 on: 08/08/2007 08:18 PM »
Quote
Lee Jay - 8/8/2007  10:09 PM

Yep...we looked into them in some detail.  There are some issues with that approach but some advantages as well.

I think the biggest issues were cargo vs. ballast exchange and wind shear. I think they never really solved the latter.

Offline Lee Jay

  • Elite Veteran
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6683
  • Liked: 982
  • Likes Given: 140
Re: 6 segment SRB?
« Reply #47 on: 08/08/2007 08:21 PM »
Quote
pippin - 8/8/2007  2:18 PM

Quote
Lee Jay - 8/8/2007  10:09 PM

Yep...we looked into them in some detail.  There are some issues with that approach but some advantages as well.

I think the biggest issues were cargo vs. ballast exchange and wind shear. I think they never really solved the latter.

Exactly.  The ballast issue invokes silly images in my head.  You have a blimp carrying a 160mT load, and you put the load down.  Next thing you know, you're heading to LEO at Mach 4.   ;)

Offline publiusr

  • Elite Veteran
  • Full Member
  • ****
  • Posts: 1540
  • Liked: 1
  • Likes Given: 2
Re: 6 segment SRB?
« Reply #48 on: 08/10/2007 06:55 PM »
If AJ 260 were around, the upper stage could have been made wider.

Tags: