A new EELV v SDV - A new spacedaily opinion piece

GCNRevenger · 2005-02-11 20:16:35

Which as calous as it may sound, that might be the price of really moving forward with a manned exploration program. The Shuttle Army never should have exsisted in the first place, and has been the biggest millstone around NASA's neck for almost thirty years.

NASA's budget is large enough to start VSE and land on the Moon, but not by much, and the $4Bn for Shuttle operations is basically the money that is slated to start VSE in earnest. Unless SDV operations can be held quite low, to say under $2.0Bn including all expendable hardware for five flights annually (under $400M each), then NASA ought to look elsewhere.

Also, unless the thing is man-rated, one of the EELVs will need to be modified as a people-carrier anyway, which will not be a trivial design expense.

A pair of "super" Delta-IV's could equal the throw weight of one SDV for about $400M, and thats with six large engines, four upper stage engines, and a gaggle of small SRMs... If SDV has a hard time beating this price with only three large engines, two SRBs, and maybe a small kick stage then the Shuttle army is what is running up the bill.

A new clean-sheet HLLV that uses half that number of engines like my "Atlas-VI," trades the SRMs for Shuttle SRBs, and only requires one set of control hardware & launch pad costs could potentially be less expensive then either SDV or Super-Delta and more flexible then SDV.

John Creighton · 2005-02-11 22:27:08

The multi-segment SRBs from Thiokol for instance, Thiokol actually lost the bid since their booster was less reliable and powerful... but they happend to be in Utah, so NASA was orderd to use them as a political favor. Their lower performance helped to scare the USAF out of the Shuttle program and less rugged construction was the technical cause for the Challenger disaster.

Just curious powerful in what sense?

GCNRevenger · 2005-02-11 22:50:53

Underpowerd enough for the USAF to ponder putting a highly truncated Titan-II stage under the Shuttle external tank to boost payload (abandoning Shuttle when it couldn't lift the payloads needed), and underpowerd enough that Shuttle itself could not reach orbit if it lost one of its main engines... which has almost happend once (Columbia computer malfunction) that likly would have been catastrophic.

Euler · 2005-02-11 23:50:13

I would be interested to see a breakdown of the shuttle army to determine what percentage of those folks work exclusively with the orbiter.

The entire "hardware" segment of the Space Shuttle budget is a little less than half of the total. About one third of the budget is used for "flight and ground operations", and the rest is split between "program integration" and R&D. Hardware includes procurement and refurbishment of all flight hardware and software. Operations includes final assembly of the shuttle stack, mission control, astronaut training, aircraft support, life sciences work, etc. Program Integration works with the payloads and does some management work.

I have not been able to find a more detailed breakdown than that. The current NASA budget does not even show how much money each category is getting, so the amounts in each segment are just what I remember from previous budgets.

GCNRevenger · 2005-02-12 07:40:47

Gee, NASA accounting isn't very helpful are they...

Each Shuttle flight requires about $100-110M to buy the external tank (~$50-60M) and a pair of ~$20-25M booster reloads... probobly a few more million for cryogenic & OMS fuel... and a few more for misc. stuff. So, NASA has to pay around $125-150M ballpark for the actual expendable stuff for a Shuttle flight. At four and a half flights a year, then that adds up to $560M-$680M for the actual "stuff." This probobly includes booster segment integration and hazardous fuel handling.

So, that places the cost of Shuttle rebuilding, refurbishing, and checkout procedure costs somewhere around $1.25-1.50Bn (45% of $4.3Bn minus expendable materials costs). NASA is going to basically have to make practically this whole expense disapear and do some major trimming on the other costs to make SDV affordable.

Assuming a manned Lunar program that calls for two manned sorties per year plus two heavy cargo sorties, then we'll need as many as six SDV flights per year (CEV, Lander/HAB, Cargo, or other stuff [JIMO]). Assuming a higher $200M materials cost with the expendable main engines, NASA must operate SDV for no more then $2.4Bn per year total to meet the $400M/each benchmark, which leaves only $1.2Bn for all vehicle staff and operations.

Non-expendable Shuttle costs run between $2.80Bn-$3.00Bn for 4.5 launches per year. Needless to say, I am worried that NASA can't cut the SDV's non-expendables budget by 60% for six flights.

Ad Astra · 2005-02-12 23:48:08

At the same time, I think that NASA could easily do 6-8 SDV flights per year under the current VSE plan. Assuming that each launch will be either a manned lander or an unmanned habitat, three or four missions per year is a realistic goal.

At this stage I think it's important to have a booster that's suited for the needs of CEV, rather than sizing the CEV system to a booster that's already available. Then again, Apollo was sized based on the Saturn V.

GCNRevenger · 2005-02-13 20:32:02

I see that there are two and a half main "routes" to the Moon, either of which will require a different launch vehicle(s):

Saturn-V style, building a man-rated heavy lift rocket in the 80MT range capable of sending the CEV to Lunar orbit, either SDV or "Mega Atlas" or whatever. A second heavy lifter would have pre-positioned the HAB/payload module with a small nuclear reactor and enough supplies 6mo/4 crew or 4mo/6 crew. Decent options include a very minimal lander for only suited astronauts with a unpressurized rover and enough fuel to return to orbit if the rover is dropped. Or, the Lander/HAB/LAV would wait for the CEV in Lunar orbit and then land.

Direct flight with both the CEV and Lander/HAB/LAV on the same rocket was okay for a week or two stay for two people, but without a Superheavy 200MT class launcher, each mission will have to be devided up to permit larger surface payloads and crews.

EOR style, where the CEV and the Lander/HAB/LAV are launched into LEO by an intermediate rocket in the 40MT range, then TLI rocket stages are launched and mated in orbit, and both stacks are sent to Lunar orbit. This method is less efficent then direct launch, but it would be possible by modifying the Delta-IV HLV, thus avoiding the cost of building a new HLLV or risking fatal cost overruns by SDV. It will also be well suited for large military satelites, large space probes, and smaller supply missions (via chemical or Solar/Ion tug) to LEO or the Moon.

One issue is man rating: that either way you are putting people on rocket with some unfavorable characteristics going for it, that any of the boosters will probobly use solid rockets to add low cost thrust, since using multiple large engines like the original Saturn-V will get awfully expensive. If this risk is unacceptable, then the crew would be launched seperatly to LEO on top of an uprated EELV+. One thing the EOR system has going for it is that a single core from the Delta-IV+ "Super Heavy" could launch the CEV with maximum safety, saving on development costs. Launching the CEV seperate from the TEI stage will give some extra payload for the TEI stage that could be sent down to the the surface too.

Of course, Delta-IV+ HLV would be much too small for any Mars vehicles.

It would also be nice to have a modular HLLV capable of launching 80MT or 40MT class payloads, so you could do supply missions to LEO or the Moon with the smaller version, send heavier payloads via Solar/Ion tug cheaply, or do other things. Such a rocket would also probobly have the highest safety for either route if sending the crew and ship together is an acceptable risk.

idiom · 2005-02-15 00:55:49

Could someone clue me in on the difference between man-rated and reliable? Does it mean escape systems or something?

It would seem to me that if you had something as labour intensive and expensive as a moon lander you would want to put it on the most reliable rocket possible. Wouldn't that be a man-rated rocket?

GCNRevenger · 2005-02-15 10:29:55

"Man rated" means that there is a 1 in 1,000 chance or less of there being a crew casulty for each mission.

Reliability is the risk that the vehicle will not do its job.

Generally speaking, you can make a rocket that is reliable enough for unmanned use without too much trouble, like 95-98% reliable like most satelite launchers. However, making a rocket that is 99.9+% reliable is much harder then making it 99.9+% surviveable. That the crew would be okay, but the vehicle would be lost.

In fact, I don't think there has ever been a launch vehicle that is 99.9% reliable. The Atlas series is close, but that might be a fluke. We will have to make a vehicle that is that reliable if we need an RLV, otherwise it will be too expensive to keep building replacements.

SpaceNut · 2024-03-17 16:56:36

It was all about what we could build from existing parts, but it was a Frankenstein that would come out of the expenditures.

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#26 2005-02-11 20:16:35

Re: A new EELV v SDV - A new spacedaily opinion piece

#27 2005-02-11 22:27:08

Re: A new EELV v SDV - A new spacedaily opinion piece

#28 2005-02-11 22:50:53

Re: A new EELV v SDV - A new spacedaily opinion piece

#29 2005-02-11 23:50:13

Re: A new EELV v SDV - A new spacedaily opinion piece

#30 2005-02-12 07:40:47

Re: A new EELV v SDV - A new spacedaily opinion piece

#31 2005-02-12 23:48:08

Re: A new EELV v SDV - A new spacedaily opinion piece

#32 2005-02-13 20:32:02

Re: A new EELV v SDV - A new spacedaily opinion piece

#33 2005-02-15 00:55:49

Re: A new EELV v SDV - A new spacedaily opinion piece

#34 2005-02-15 10:29:55

Re: A new EELV v SDV - A new spacedaily opinion piece

#35 2024-03-17 16:56:36

Re: A new EELV v SDV - A new spacedaily opinion piece

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