SRB booster for CEV

BWhite · 2004-09-14 17:02:56

So, now we have the Bush administration trying to put together a "what now?" to keep NASA going, and the decsion was reached for a number of contributing factors... that the project(s) not be destined for LEO, too boring, and nobody will fall for the "$9Bn for ISS for science! honest!" line again. Then the China moon mission angle. Then sustainability too, the program must be cheaper than Apollo and be open-ended. And help make launchers for the military bigger and more available... But mostly to protect NASA from the "robots can do it cheaper!!!" croud and give 2/3rds of NASA's money to Social Security. What it does is give us reliable and sufficently inexpensive access to LEO and cis-Lunar space to sustain small to moderate science & development operations indefinatly without making NASA go broke for really a minimum of development dollars to not do a half-baked job.

How can you say reliable and inexpensive when the CEV designs remain 3-D drawings as of today

Yes, it is possible that keeping KSC open would actually help advance manned spaceflight even if it were more expensive, but I think that NASA simply cannot afford another Shuttle-like situation where launch costs and ISS/STS maintenance utterly bankrupt the agency. If NASA does not do this, then there won't be any NASA anymore... Everything that has to do with Shuttle since the Nixon days has been about one thing: Maximize engineer employment, and like many results when NASA really tries, has suceeded beyond any expectation. I question if NASA has the willpower to fix this hardest of problem: "redesigning" KSC to change course and fulfill a new goal.
So, if NASA does not have the willpower to "fix" KSC to stop maximize manpower and spending, then KSC has to go, and it would be better to start over again... Maybe at the Boeing Delta-IV plant up the coast...

Fair enough.

So raze the VAB and most of the Pad 39 tower. Why can't you launch a Thiokol SRB booster from the Pad 39 concrete and flame trench and assemble it on the pad with a single crane?

Stack up the segments at the Pad and top it off with the upper stage processed elsewhere. Ask Thiokol to practice.

Really, how hard could that be compared with mating the SRBs to the ET and adding the orbiter?

GCNRevenger · 2004-09-14 19:51:04

Because the technology is simple, proven, and available. Capsules are not that hard to engineer, neither is a small OMS/Service module with a Kerosene/Peroxide or Hypergolic engine, and the launchers are available or with only modest modification... We have done them before without costing too much, and we'll do them again. The launchers today are reliable enough with the use of a good escape system, which Lockheed already has in the works... The CEV can be done, the reason it doesn't have a clear shape yet is because we're still trying to figure out what we want it to do, not so much we don't know how to do it.

Short term orbital missions? Medium term Lunar missions? Lunar landing option? TLI stage compatibility? Choice of fuels? Multiple services module types? Inflatable orbital module ala Soyuz? Crew size? Cargo-only option? Reuseability? Decent angle? Powerd cross-range? Landing rockets? Surface or water landing? Transfer-orbit velocity reentry? Lifetime on orbit? Airlock/repair orbital module option?

...There are quite a few paramters that NASA has to narrow down before they go beyond pretty 3D pictures. It is unlikly that the launcher for CEV will exceed $200M by much, and if the CEV can be built for $100M each (fairly generous), then $300M for a flight is not a bad deal compared to a $1.1Bn Shuttle shot.

Rebuilding the Pad-39 complex is a bigger deal then it sounds, you would need some kind of arrangement like the Delta-IV pad if you are going to do verticle integration, which would require large-scale changes to the launch pad structure, particularly the tower... You really might as well build a new one. This isn't quite like handling a liquid rocket either, each segment is a delicate, armed BOMB... see the Brazilian satelite launcher.

PurduesUSAFguy · 2004-09-14 22:32:33

Just out of couriosity has any given serious thought to a clean sheet design?

PurduesUSAFguy · 2004-09-14 22:40:12

Because the technology is simple, proven, and available. Capsules are not that hard to engineer, neither is a small OMS/Service module with a Kerosene/Peroxide or Hypergolic engine, and the launchers are available or with only modest modification... We have done them before without costing too much, and we'll do them again. The launchers today are reliable enough with the use of a good escape system, which Lockheed already has in the works... The CEV can be done, the reason it doesn't have a clear shape yet is because we're still trying to figure out what we want it to do, not so much we don't know how to do it.
Short term orbital missions? Medium term Lunar missions? Lunar landing option? TLI stage compatibility? Choice of fuels? Multiple services module types? Inflatable orbital module ala Soyuz? Crew size? Cargo-only option? Reuseability? Decent angle? Powerd cross-range? Landing rockets? Surface or water landing? Transfer-orbit velocity reentry? Lifetime on orbit? Airlock/repair orbital module option?
...There are quite a few paramters that NASA has to narrow down before they go beyond pretty 3D pictures. It is unlikly that the launcher for CEV will exceed $200M by much, and if the CEV can be built for $100M each (fairly generous), then $300M for a flight is not a bad deal compared to a $1.1Bn Shuttle shot.
Rebuilding the Pad-39 complex is a bigger deal then it sounds, you would need some kind of arrangement like the Delta-IV pad if you are going to do verticle integration, which would require large-scale changes to the launch pad structure, particularly the tower... You really might as well build a new one. This isn't quite like handling a liquid rocket either, each segment is a delicate, armed BOMB... see the Brazilian satelite launcher.

100 million for an expendable basic CEV cabin sounds more the generous, I would have guessed more along the lines of between 30-45 million plus whatever inflatables or other mission componets you add on.

I agree it doesn't make alot of sense to launch from pad 39a and b for EELVs. Prehaps it would be cheaper to launch from a new facility at Vandenburg?

The thing I am not comfortable with is an EELV derivative for cargo launch. 80 tonnes seems very much on the low end of the spectrum if we are serious about going beyond the Moon. (I still maintain that the Moon and Mars make more sense in parallel not as luna being a prerequisite) It seems there is where an SRB or Shuttle derived launcher would make sense.

I appologize for the spelling but crazy old Ivan (skyy vodka) is flying his mig around in my stomach right now, I had to celebrate the end of my first Neutron Mechancics exam.

SpaceNut · 2004-09-15 06:09:18

GCNRevenger while Large reuseable cryogenic engines, metal heat shield, LOX-augmented jet engines, composit structures and tankage, advanced CAD/CFD design... are parts of a reuseable design. Metal shields are heavy and would need complete replacing between missions.

Why were these enhancements not implimented on the current shuttle as we go?

I think a lot of the x series demonstrators were just for that purpose but were heavily burdened with cost overrun and technical as well as material failures in implementation.

GCNRevenger · 2004-09-15 08:49:06

I think that $100-150M a copy should be the absolute maximum limit allowed by contract, if it costs more then that each to build a CEV and its service & orbital modules, then the manufacturer pays the difference.

EELVs are currently NOT being launched from the KSC complex, but rather from Lockheed/USAF and Boeing/USAF facilities constructed specificly for each EELV. Boeings' facilities are substantially larger, but the Atlas-V rockets are slightly smaller physicly.

For a sustained Lunar program, I think that it can be pulled off with a 40MT class rocket, which can be built as a derivitive of either EELV without breaking the bank... This was the original plan for the Apollo program, to build medium rockets and assemble Lunar vehicles in LEO. Instead, in order to beat the Commies to the Moon, NASA went with the faster option, the Saturn-V megarocket and do it all at once. Unfortunatly, the Saturn-V turned out to be extremely expensive, almost three billion dollars per flight. Making a giant >80MT launcher out of EELV cores probobly does not make good sense, and a SDV or clean-sheet launcher would be better.

The reason that Shuttle has not really been upgraded much over the years is mostly because of one simple, monolithic, unyeilding, terrible fact:

The Space Shuttle is the most complex machine ever devised by man

There are no "simple cheap modifications." If any major system is changed, you might as well just start over, it would probobly cost less for the vehicle you would build... Furthermore, a metal heat shield is possible, as the shield for lift body vehicles does not get as hot during reentry as the Shuttle's shield because of its shape... Shuttle is pointy with a small heat shield to maximize cross-range for the USAF to make Polar missions easier. A lift body is broad and blunt, spreading the heating out, so that a metal heat shield able to last for multiple missions is possible. The VentureStar was supposed to have a simple steel heat shield, and metal alloy/composit materials have been produced that should last for many flights, perhaps the life of the vehicle with good insulation.

Certainly enough to go as long between replacements as the main engines would need an overhaul, (10-20 flights, maybe more), and replacing big pizza-box sized metal pannels is easy... just undo the bolts and bolt on a new one. No felt, no glue, no vacuum testing, no scotch-guarding, no nothing. Just bolts.

BWhite · 2004-09-15 19:45:26

I wonder how high the GCNRevenger meter will register with this idea. . .

http://thomasc.stanford.edu/aw50_54.pdf]Wax SRBs. Seriously, paraffin wax SRBs.

>> 10% higher ISP than the current Thiokol RSRM.

>> No toxic combustion products

>> Little health or safety risks for the crews building the things.

>> Being hybrid rockets they can be shut off by closing the oxidizer valve - - a major safety improvement.

In the presence of normal Terran air, the fuel burns like candle wax (which it is). In the presence of pure gaseous O2 or LOX it out-performs the current Thiokol solid fuel formula.

COOL!

Hey folks, lets light this candle!

= = =

http://thomasc.stanford.edu/research.ht … 62]Another link

GCNRevenger · 2004-09-15 21:02:40

Yeaaah i've heard of this idea before... it may have pretty decent Isp, but I am skeptical as to how easy it is to scale up the concept and make serious thrust. When you need to really squeeze serious performance and thrust out of a given set of dimensions, how will the thing behave? Will any hybrid rocket of any kind be able to match regular Aluminum + Perchlorate propellant?

BWhite · 2004-09-15 21:47:00

Yeaaah i've heard of this idea before... it may have pretty decent Isp, but I am skeptical as to how easy it is to scale up the concept and make serious thrust. When you need to really squeeze serious performance and thrust out of a given set of dimensions, how will the thing behave? Will any hybrid rocket of any kind be able to match regular Aluminum + Perchlorate propellant?

It looks like those Stanford guys are going to give it a shot.

The only way to really answer your questions is to build a few intermediate size paraffin rockets and see how they do.

GCNRevenger · 2004-09-16 07:38:02

I have my doubts that they can achieve high enough pressures and exhaust velocities to compete with conventional solid fuels... "candle in a hurricane" and such.

Take note that the PDF article is comparing the Parafin/GOX hybrid engine to another hybrid engine powerd by regular solid rocket fuel, but minus the oxidizer - not a regular SRM.

mboeller · 2004-09-16 10:27:57

Take note that the PDF article is comparing the Parafin/GOX hybrid engine to another hybrid engine powerd by regular solid rocket fuel, but minus the oxidizer - not a regular SRM.

According to this page [ http://www.braeunig.us/space/propel.htm … propel.htm ] I found with google, the Space Shuttle SRB's have an Isp of 242sec at sealevel and 269sec in space.

This is far lower than the 295-300sec quoted for the candle wax Hybrid in the AW&ST-article. Therefore the comparison from BWhite seems about right.

GCNRevenger · 2004-09-16 11:07:05

Yes the specific impulse is a little bit better, but raw specific impulse at low altitudes and speeds is not as important as it is for an upper stage or a orbital transfer engine. A booster rocket is supposed to generate massive amounts of thrust, the Shuttle boosters are almost double the thrust of the giant Saturn-V F-1 engines. To date, Hybrid engines have not been able to produce good thrust, and I am questioning how well this solid hydrocarbon Hybrid behaves as you dial up the internal pressures and temperatures. And it may not be that easy to handle, if you get the thing above 35C before launch, the fuel grain may simply melt... better not leave your booster in the hot sun!

Oh, and unless you go that crazy route of a hydrogen-preburner-helium-heating tank pressurization system, you will still need a LOX turbopump.

And if you will read the article carefully, the engine needs a longer and longer "combustion chaimber" following the fuel grain but preceeding the exit cone with higher pressures, which will make the Hybrid rocket inherintly have higher empty mass too, particularly at high thrusts and burnup rates.

BWhite · 2004-09-16 12:30:30

Yes the specific impulse is a little bit better, but raw specific impulse at low altitudes and speeds is not as important as it is for an upper stage or a orbital transfer engine. A booster rocket is supposed to generate massive amounts of thrust, the Shuttle boosters are almost double the thrust of the giant Saturn-V F-1 engines. To date, Hybrid engines have not been able to produce good thrust, and I am questioning how well this solid hydrocarbon Hybrid behaves as you dial up the internal pressures and temperatures. And it may not be that easy to handle, if you get the thing above 35C before launch, the fuel grain may simply melt... better not leave your booster in the hot sun!
Oh, and unless you go that crazy route of a hydrogen-preburner-helium-heating tank pressurization system, you will still need a LOX turbopump.
And if you will read the article carefully, the engine needs a longer and longer "combustion chaimber" following the fuel grain but preceeding the exit cone with higher pressures, which will make the Hybrid rocket inherintly have higher empty mass too, particularly at high thrusts and burnup rates.

All of which underlines how successful the current Thiokol RSRM has proven itself to be. 99.5% success in crewed launches.

GCNRevenger · 2004-09-16 12:44:48

Which I have no trouble agreeing with Bill, I just am not really fond of using it alone as a launch vehicle when we would have to operate a different rocket for manned flights anyway... Particularly at KSC.

I would be satisfied seeing a large 5-segment SRB, or somthing like it a little simpler, grouped around a HLLV cryogenic core powerd by Regenerative RS-68 engines... Four, perhaps six maybe.

SpaceNut · 2005-08-30 11:38:07

Just think we were talking about this so long ago but had to wait for the changing of the guard and a 60 plus day report to get to this same point that we all were clamering about...

Ad Astra · 2005-08-30 19:47:29

I agree it doesn't make alot of sense to launch from pad 39a and b for EELVs. Prehaps it would be cheaper to launch from a new facility at Vandenburg?

Due to Vandenberg's location, it can only be used for high inclination (polar or near-polar) missions. This is very neat, but doesn't nelp us if we want to get to the ISS, the moon, Mars, or any place that's exciting.

The cursed SLC-6 launch pad at Vandenberg was supposed to launch manned missions to polar orbit--originally with the Titan IIIM (Manned Orbiting Laboratory,) and then with the DoD shuttle missions. All of these plans were scrapped.

Back when EELV was under consideration to launch the CEV, I held out hope that human missions to polar orbit could be launched with the EELV + CEV combo. Ironically enough, Delta IV will launch from SLC-6. With EELV yielding to "The Stick," the dream of man in polar orbit is fading yet again.

publiusr · 2005-08-31 15:35:52

The Stick is far more rugged--and I do not buy the idea that EELVs can truly beat it in terms of price. SRBs can more easily fly depressed trajectories--are already man-rated--need only a single core, etc.

publiusr · 2005-08-31 15:37:01

Let's hope the hurricane didn't spoil the plans before OMB

Ad Astra · 2005-08-31 18:20:02

Current damage assessments on Michoud indicate that the plant got off fairly lightly after the hurricane. It's doubtful that power will be restored anytime soon, however. As for The Stick, development will be unaffected since the SRB plant is in Utah.

Imagine how things would have been different if NASA selected Aerojet as the SRB contractor during the 70's. Aerojet's single-segment design would have been safer, but the Florida manufacturing plant would have been more vulnerable to hurricanes than the eventual Thiokol plan in Utah.

As for the space shuttles themselves, I have it on good word that STS-121 was facing delays (past March 2006) before the hurricane hit; damage to Michoud is a secondary worry right now.

GCNRevenger · 2005-08-31 19:26:33

Well, it'll give them time to come around to the obvious fix for the ET, which is to wrap the orbiter side of the tank with mesh or something, and tell the Boeing/ESA/JAXA that they are going to have to lighten the load a little.

BWhite · 2005-08-31 20:05:35

The Stick is far more rugged--and I do not buy the idea that EELVs can truly beat it in terms of price. SRBs can more easily fly depressed trajectories--are already man-rated--need only a single core, etc.

Why wouldn't the Stick beat EELV handily on price per launch?

4 segments cost $35M today. 5 segments for $45M?

Okay we need a J-2 or equivalent and the stacking remains etc. . .

GCNRevenger · 2005-08-31 20:50:12

Two big questions:

How much is that upper stage going to cost? The 30MT version of The Stick requires an SSME engine, which cost about $40-50M a pop at the moment. If NASA can't get a bulk deal or build a simplified version, that would be a hefty reoccuring expense. The J-2 engine line no longer exsists, and even if it did, using the J-2 will cut the payload down to 25MT or so. The tank and guidence hardware is suseptable to "price creep" too I bet, unless Griffin gets tough with the contractors.

Then there is the cost of actually putting the thing together and flying it using the "restructured" Shuttle army and KSC facilities.

Its possible that The Stick will be cheaper then the stock ~$200M Delta-IV HLV kilo-for-kilo, but not a sure thing, and if you are talking about non-manned payload then the Delta-IV with a six-pack of small solid rocket motors and RL-60 engines could probobly overtake The Stick kilos-per-dollar.

SpaceNut · 2005-09-01 09:56:10

Right now seems the perfect time to make use of the developement time and money since those out of work will not be on payrole for a while at Michoud.
Shift upper stage engine and tank devlopement for the upper stage elsewhere as well. Do less design and more building of the stick. Review design after prototype launch, sensor the cramp out of it to get the most info that you can for later rehash of the design.

publiusr · 2005-09-01 13:08:17

I think Griffin will get tough. He has an excuse to ground the shuttle fleet immediately with the hurricane as an excuse.

Here is my plan.

STS--the orbiter that is--is done, as is ISS. Russia, you just won a space station. We want visiting rights however.

All NASA money goes into dual HLLV/Stick development. As Michold is repaired, HLLV blueprints are prepared at Marshall--and all non-LV work there suspended. By the time the design is finalized, Michold should be up and running, and Stennis can put HLLV cores up for static tests. ATK, far from the South will work on the Stick--and Marshall kept the hell away from CEV.

One of the shuttle launch pads is modified.

By 2008 the first HLLV and Stick should be ready for launch, as one last shuttle flight is brought on line for Hubble to return STS for its final flight.

Sound like a plan?

GCNRevenger · 2005-09-01 14:26:42

Sounds good, but I would put the time frame around 2009-2010, and leave a "plan B" in the event that Michoud is out of the picture.

And no Hubble servicing mission. Its not worth it... The orbiter batteries are removed, maybe the engines stripped out, and all three of them are in museums before Jan 1st 2006.

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#26 2004-09-14 17:02:56

Re: SRB booster for CEV

#27 2004-09-14 19:51:04

Re: SRB booster for CEV

#28 2004-09-14 22:32:33

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#31 2004-09-15 08:49:06

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#32 2004-09-15 19:45:26

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#35 2004-09-16 07:38:02

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#36 2004-09-16 10:27:57

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#37 2004-09-16 11:07:05

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#38 2004-09-16 12:30:30

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#39 2004-09-16 12:44:48

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#40 2005-08-30 11:38:07

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#41 2005-08-30 19:47:29

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#42 2005-08-31 15:35:52

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#43 2005-08-31 15:37:01

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#44 2005-08-31 18:20:02

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#45 2005-08-31 19:26:33

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#46 2005-08-31 20:05:35

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#47 2005-08-31 20:50:12

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#48 2005-09-01 09:56:10

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#49 2005-09-01 13:08:17

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#50 2005-09-01 14:26:42

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