Delta IV Heavy and Beyond

Mark S · 2004-09-09 22:53:50

I've looked over some of Boeing's proposals, and some look promising while others seem impractical. Eventually the cost analyses will show which ones are viable.

Al-Li tanks are a no-brainer, but other mods aren't as obvious. How much will modifications to the RS-68 engines require? Densified propellants will require regenerative cooling on the engines. Cross-feeding would improve the vehicle's engine-out survivability, but it will also add to the cost of the new vehicle.

New facilities for the 5 and 7 CBC variants defeat the purpose of advanced Delta IV derivatives. If Boeing wants to build new pads, they should go with a new design of a wider diameter and different length, while still using Delta engines and construction methods.

SpaceNut · 2004-09-13 11:43:36

As you noted by creating a new topic for SRB booster for CEV. It is important to get this first step right. Using atlas or delta rocket which are not man rated every with the argument of high success rate just will not do. Partly because a full analysis and possible redesign would mean that it might not be so successful not to mention costing billions.

Mark S · 2004-09-13 12:25:07

If Delta IV can get some launches under its belt, we might be able to make a better call on whether we want an evolutionary upgrade of the EELV's or something new and revolutionary. Right now, the facts support an evolutionary upgrade.

Honestly, I think some of the safety concerns have been mitigated over the years. Having multiple, independent CBCs on the first stage does multiply your failure rate, but then again the failure rate on modern ELV's has been quite good. It's around 1% for Delta II and 0% for the now-retired Atlas II. Part of these vehicles' heritage is that they evolved from rockets with much higher failure rates: the Thor/Delta and Atlas ICBM/Atlas-Agena/Atlas-Centaur series.

The more we build and fly, the more we learn. Delta IV and Atlas V haven't been flown enough to establish their reliability as ELV's, but if they are on par with their predecessors, we will be well served.

Mark S · 2004-09-13 12:42:33

I did some checking on astronautix.com and got some good statistics for the Delta II (The Delta 7000 series.) It has had one total failure and one partial failure in 96 launches. Both instances of failure had to do with the solid rocket motors.

I'm starting to lean aginst SRMs for a Delta IV upgrade, but I'm also thinking about the reliable Delta II core for new launchers. Maybe a Delta II cluster (like the MDD Barbarian) or an RLV based on the Delta II first stage tankage and engine could produce useful boosters.

GCNRevenger · 2004-09-13 12:43:21

Do recall also that the question of man rating is not if the rocket works and puts the CEV into orbit safely a given number of times compared to its failures, but rather how many times the crew survives per launch. A liquid fueled rocket with a good escape system may meet man rating requirements even if the booster itself isn't >99.9% reliable.

It is also possible that the CEV could be built light enough to fly on a single core EELV with some upgrades, like the Delta-IV with Lithium/Aluminum tanks and regenerative RS-68 engines or the Atlas-V with larger fuel tanks and a more powerful Centaur stage.

Mark S · 2004-09-13 13:35:51

GCNRevenger, I totally agree. We should be more concerned with preventing loss of crew as opposed to loss of vehicle. Man-rating it would consist of extra instrumentation that would trigger the escape tower if a failure was detected in one of the rocket stages, such as loss of tank pressure, engine overheating, or loss of thrust.

Grypd · 2004-09-13 14:14:33

What would it cost to create a Man-Capable delta with escape tower. I honestly think it could be done reasonably quick and cheap. It is the solid motors that have failed and the Delta uses a lot of them there are options to create a non solid boosted rocket. It now comes to cost of flights.

GCNRevenger · 2004-09-13 14:24:34

Actually, Lockheed is working on the escape rockets now with their PADD demonstrator...

Man rating either of the EELVs should not be a huge problem, there would need to be various sensors added to the first and second stage engines, command computer link between the Centaur equipment bay and the CEV, and a full-up unmanned test series of EELV/CEV launches where the escape system is demonstrated.

I'm wondering if the escape rockets could switch to gelled fuels like fighter jet ejector seats and missiles, so there would be at least some ability to vary the thrust.

Modifying the Atlas-V with larger fuel tanks and possibly an RL-60 upper stage could make it possible to launch the Earth-LEO CEV with no SRBs at all. I wonder if the Delta could do the same with Lithium/Aluminum fuel tanks and a regenerative RS-68... So, with the RL-60 upper stage, you could launch the whole CEV and only have to rely on two liquid fueled engines... which you can shut down and have a little warning if they are about to blow.

As an added perk, these uprated booster-free EELVs, when equipped with the maximum loadout of boosters, could lob around 40MT into orbit... which would be about the perfect size for anything NASA wants to do until we start thinking Mars missions. 40MT to launch two TLI stages, one large Lunar lander, one orbital transfer vehicle, and one manned CEV into LEO. Earth to the Moon for a billion dollars worth of launchers or so.

Tripple-core Delta-IV with Al/Li tanks, RS-68 regenerative main engines, possibly the Rl-60 upper, Slush LH2 fuel, and 4X SRMs could hit about 40-45MT with no facilities modification.

Fatter "Atlas-VI" core, with 6X of its larger SRMs, RL-60 upper stage, perhaps build the thing from Al/Li too.

SpaceNut · 2004-09-24 07:00:44

Heavy Lift Is Needed
http://www.spacedaily.com/news/oped-04zc.html

Sentiment in the last round of senate appropriations do concor that beyound the shuttle to carry out the vision heavy lift is a necessary part of the plan.

SpaceNut · 2004-10-11 06:49:07

Florida's hurricane troubles Have forced this to be rescheduled. With this delay they will be going back though the rockets control systems and more to be sure that every thing will go as planned.

New launch date announced for Delta 4-Heavy debut
http://www.spaceflightnow.com/news/n0410/10delta4heavy/

infocat13 · 2004-10-31 19:00:53

This is a really a great thread................
some questions,
(A) the trade on costs of employment and infrastruture on the shuttle C idea.If moon direct used shuttle C for cargo only what percentage of the launch costs in the work force would we need?Ditto the work force needed for man rated heavy EELV?
(B)EELV and the trade of mass production of launch vehicle componants with the need of alot of earth orbit Rendezvous.
IE one failure means your earth orbit stack is in trouble?

GCNRevenger · 2004-10-31 21:16:20

I think that it is a tossup if Shuttle-C (~80-90, maybe 100MT each) would cost less then a pair of Delta-IV Superheavies (40-45MT each), Shuttle-C will probobly cost more to develop and NASA would have a difficult time bringing itself to part with enough of the Shuttle Army to get launch costs down to under $500M each. The Delta is probobly the safer bet, though it would be slightly less capable.

As for the loss of payload issues, Lunar mission "stacks" would only have two launches each, one for the payload and one for the Earth-Moon rocket stage. Smaller payloads could perhaps be launched directly to the Moon in a single shot if the 2nd stage tanks were enlarged.

BWhite · 2004-10-31 21:34:23

I think that it is a tossup if Shuttle-C (~80-90, maybe 100MT each) would cost less then a pair of Delta-IV Superheavies (40-45MT each), Shuttle-C will probobly cost more to develop and NASA would have a difficult time bringing itself to part with enough of the Shuttle Army to get launch costs down to under $500M each. The Delta is probobly the safer bet, though it would be slightly less capable.
As for the loss of payload issues, Lunar mission "stacks" would only have two launches each, one for the payload and one for the Earth-Moon rocket stage. Smaller payloads could perhaps be launched directly to the Moon in a single shot if the 2nd stage tanks were enlarged.

I agree there are competing factors. I am a big SDV guy yet that does not mean there are not at least 2 sides to the question. Probably many more than that.

Okay, add a liquid upper stage to Shuttle C and the payload increases substantially.

Also, improve 85/15 mass fractions on the RSRMs and that turns into payload. No incentive to do that with orbiter, the extra mass couldn't be lifted anyway.

But, with shuttle C or Ares, alter that 85/15 mass fraction to 90/10 and that adds 128,000 pounds! (yup) to your second stage. Use composites or carbon fiber or even fiberglass in low stress locations. (Remember there are 2 SRBs)

RSRM = SRB, the first R means resuseable.

The 15% weighs it at 192,000 per RSRM. Change that to 10% and you can add 1/3 of 192,000 onto your 2nd stage payload per SRB. If you can go to 92.5%/7.5% maybe just give up on recovery and let the SRBs be 100% disposable.

2000's materials technology can surely do better than 1970's aluminum technology and if we add 100,000 pounds to a standard shuttle C payload, well it would seem to blow Delta IV away.

= = =

Fantasy time.

Go highly exotic composites and make the SRB 100% disposable. Achieve a 95/5 mass fraction and your shuttle C can add 256,000 pounds IN ADDITION to the base payload to LEO.

GCNRevenger · 2004-10-31 21:55:21

Fantasy time.
Go highly exotic composites and make the SRB 100% disposable. Achieve a 95/5 mass fraction and your shuttle C can add 256,000 pounds IN ADDITION to the base payload to LEO.

Thats extra mass added to the rest of the stack, not to the final payload mass, which will be a signifigantly smaller gain.

I don't think that it will be easy to so radically change the boosters, making such a large composit structure which must resist high mechanical (stresses and internal pressure) and thermal loading, metals may actually be preferable, and I bet that you really really don't want to know how much an all-composit SRB would cost. The vast majority of the empty weight of the SRB doesn't have a "low stress" area, since its being used to hold back the insane forces from the world's biggest rocket engine.

I'm not thinking about adding a liquid upper stage to the Shuttle-C design at all, instead putting one on the payload inside the payload faring, and only firing it in orbit for a TLI/TMI burn. If you are going to do a big second stage, you might as well put the payload faring on top in line with the tank, which will cost big bucks to modify.

BWhite · 2004-10-31 22:46:02

Fantasy time.
Go highly exotic composites and make the SRB 100% disposable. Achieve a 95/5 mass fraction and your shuttle C can add 256,000 pounds IN ADDITION to the base payload to LEO.
Thats extra mass added to the rest of the stack, not to the final payload mass, which will be a signifigantly smaller gain.
I don't think that it will be easy to so radically change the boosters, making such a large composit structure which must resist high mechanical (stresses and internal pressure) and thermal loading, metals may actually be preferable, and I bet that you really really don't want to know how much an all-composit SRB would cost. The vast majority of the empty weight of the SRB doesn't have a "low stress" area, since its being used to hold back the insane forces from the world's biggest rocket engine.
I'm not thinking about adding a liquid upper stage to the Shuttle-C design at all, instead putting one on the payload inside the payload faring, and only firing it in orbit for a TLI/TMI burn. If you are going to do a big second stage, you might as well put the payload faring on top in line with the tank, which will cost big bucks to modify.

All I am saying is that these questions deserve to be carefully investigated before final decisions are made.

A single SRB plus LH2/LOX upper would benefit nicely from changing the mass fractions. Whether its feasible seems worth the cost of some studies. IMHO an affordable (which is a big IF) expendable with a very high mass fraction, 95/5?, would seem a far better option for cargo.

Put crew in the Rolls Royce space-plane and launch cargo on top of fuel held in place by as little structure as can be engineered.

GCNRevenger · 2004-11-01 00:01:13

I dunno the only way to improve mass fraction over what it is now is to switch to a composit structure, but if you change up the aluminum casing for composits it won't even be the same rocket anymore. It'll be a whole new vehicle with some guts pulled out of the old one, and would have to be re-tested from scratch to make sure none of the castings give. It ain't gonna be cheap any which way, to develop or to build a composit solid rocket motor that big. The whole point of doing Shuttle Derived is to save as much money on development and new infrastructure as possible, and basicly throwing away the beautiful SRBs, with such radical alterations that they really become new engines, is a step in the wrong direction. No studies required.

If we need payloads greater then 120MT to orbit, which is what we can do with Shuttle Derived theoreticly, we may as well go clean-sheet and just add more boosters. How about four 5-segment SRBs around a core with 5x RS-68R topped by an upper with one more RS-68R?

Theres' somthing to be said for making a cargo rocket sturdy enough to increase reliability to, even at the cost of some payload. If its going to cost a billion or two to build a Mars hab, fuel plant, etc then losing one of those near priceless payload is not an option. As for spaceplanes, they aren't gonna happen until we need weekly access to space or we need a real RLV, the most exotic thing people will be flying in would be Lockheed's lift-bullet/sled CEV, or more likly the Boeing/Orbital/Northrop Big Apollo.

SpaceNut · 2004-11-01 09:28:32

On SDV the only thing reused will be the SRB, which do not cost all that much when compared to the rest of the rocket that would be treated as expendable for the shuttle C flavor. Getting the cost of making them lower and the number of personel to launch are only part of the equation for Nasa success with SDV.
With any Boeing or Lockheed derivative you only pay the flat fee and your done.

Ad Astra · 2004-11-18 21:42:27

Al-Li tanks are inexpensive to develop and would increase the capacity of the Delta IV, but they should only be used for missions where the extra lift is needed. Al-Li is much more expensive than Al; hence the reason why it wasn't used in the first place (Delta IV is about as close as we will get to a "big dumb booster.") Both cores should remain in production.

SpaceNut · 2004-11-19 06:33:20

Yup I quite agree with you on the materials use, cost and for when it would be the right time to make the change of the tanks to be used.

GCNRevenger · 2004-11-19 10:02:39

I would like to know how much of a difference using Al/Li alloy will make to the cost of the rocket compared to the total cost. Shuttle's main tank uses quite a bit of the stuff, and its cost is not outrageous.

If VSE does rely extensively on Delta, then the light-weight model will be demanded because then the Medium model could loft the orbital CEV without SRM boosters, and the Lunar payloads will probobly demand the largest practical vehicle. Dump the old aluminum tanks.

Rxke · 2004-11-19 11:07:55

It would probably turn out to be more costly to have two versions Al and Al/Li manufacturing... You'd probably have to double the workforce, floorspace etc etc... each it's own specialists and so on...

So yes, scrap the Alu, Th current Al/Li is probably expensive because of low use... So low output from factories... If producers would be guaranteed a market, you betcha they'd be able to produce on a bigger scale, hence lower cost.

Bring on the Al/Li Space age!

Euler · 2004-11-19 12:46:38

So yes, scrap the Alu, Th current Al/Li is probably expensive because of low use... So low output from factories... If producers would be guaranteed a market, you betcha they'd be able to produce on a bigger scale, hence lower cost.

There are a lot of manufacturing difficulties associated with Al/Li alloys that drive the cost up. If these problems are solved, the cost could be reduced significantly. However, it would still be more expensive than traditional aluminum alloys due to Lithium's $300/lb cost.

RobertDyck · 2004-11-19 15:56:34

Lithium is expensive, but according to http://minerals.usgs.gov/minerals/pubs/ … 8.pdf]USGS the price at the end of 1997 & 1998 was $43.33 per pound. Even silver costs only $7.50 per troy ounce (+/-10%) which is $109.37 per pound.

Ad Astra · 2004-11-19 16:00:32

One of the elementary principles of economics is scarcity. If a material is scarce, it is bound to be more expensive. Lithium is scarce, and it costs much more than standard aluminum.

I don't know what it would cost to produce both the standard and lightweight tanks concurrently. Floorspace and money could be saved if the plant alternated between production runs of Al and Al-Li tanks instead of building both at the same time. I tend to think that this setup could still be justified in the face of Al-Li's higher cost. Really, I think the Al-Li tankage should only be used for the manned version of Delta IV. That way, the weight savings could eliminate the need for the failure-prone solid rockets, and you could possibly get away with launching the CEV capsule on a single-core booster.

GCNRevenger · 2004-11-19 19:10:25

One thing that is a certainty is that the Moon will be out of reach of the standard Delta-IV HLV, and the scale of Lunar operations will depend almost entirely on launcher capacity, since no Lunar program can be accomplished if it requires too many launches.

If the heavy lift route to the Moon is avoided for whatever reason, either clean-sheet being too expensive to develop or shuttle-derived being too expensive to operate (shuttle army and all that), then some EELV derived rocket will probobly be called for since they would have low development costs plus reasonable and known price per launch.

These two things taken together will demand the biggest EELV that is practical to make without radical alteration, which will be the Delta-IV HLV with all the bells & whistles, including Li/Al tankage, which can theoretically lift 40-45MT without major change to the vehicle, factory, or exsisting pad.

$10M will buy you 115MT of Lithium too.

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#26 2004-09-09 22:53:50

Re: Delta IV Heavy and Beyond

#27 2004-09-13 11:43:36

Re: Delta IV Heavy and Beyond

#28 2004-09-13 12:25:07

Re: Delta IV Heavy and Beyond

#29 2004-09-13 12:42:33

Re: Delta IV Heavy and Beyond

#30 2004-09-13 12:43:21

Re: Delta IV Heavy and Beyond

#31 2004-09-13 13:35:51

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#32 2004-09-13 14:14:33

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#33 2004-09-13 14:24:34

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#34 2004-09-24 07:00:44

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#35 2004-10-11 06:49:07

Re: Delta IV Heavy and Beyond

#36 2004-10-31 19:00:53

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#37 2004-10-31 21:16:20

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#38 2004-10-31 21:34:23

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#39 2004-10-31 21:55:21

Re: Delta IV Heavy and Beyond

#40 2004-10-31 22:46:02

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#41 2004-11-01 00:01:13

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#42 2004-11-01 09:28:32

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#43 2004-11-18 21:42:27

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#44 2004-11-19 06:33:20

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