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#360
by
Antares
on 02 Jul, 2010 20:11
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Too complicated to answer. Really requires a trajectory optimization program.
I don't think it would happen anyway. NASA is going to have to take the Hippocratic oath when it gets serious about humans on EELV.
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#361
by
edkyle99
on 03 Jul, 2010 00:25
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Hypothetical question if I may, suppose DIVH is selected to launch a ISS & BEO Orion. Is it likely the crossfeed option (from booster to core) would happen?
What kind of extra performance could be expected? (assuming 68A) Thanks!
Crossfeed isn't needed, but RS-68A with human rating upgrades is needed. The 2009 Aerospace study linked below examined this question. It found that the existing rocket (once upgraded with RS-68A) could do either job, but Delta IV would need some "human rating" upgrades to meet crew safety requirements.
http://www.nasa.gov/pdf/377875main_081109%20Human%20Rated%20Delta%20IV.pdfThe rocket essentially exists. Now, if only there were a spacecraft...
- Ed Kyle
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#362
by
JosephB
on 03 Jul, 2010 03:20
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In addition, for an ISS Orion, a second stage isn't even needed. (bottom of page 14, section 2.2.5) So close yet so far away?
Since J-2X will likely be a reality, who knows?
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#363
by
JosephB
on 12 Jul, 2010 16:06
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When the last shuttle flight has flown and NASA begins a new wish list for heavy payloads to ISS, I wonder if DIVH will see some action?
Any thoughts on this?
Maybe using that shuttle payload carrier mentioned in one of the ULA papers?
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#364
by
sdsds
on 12 Jul, 2010 18:22
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#365
by
JosephB
on 12 Jul, 2010 18:56
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Thanks! I hadn't seen that one.
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#366
by
Jim
on 13 Jul, 2010 00:28
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When the last shuttle flight has flown and NASA begins a new wish list for heavy payloads to ISS, I wonder if DIVH will see some action?
Any thoughts on this?
Maybe using that shuttle payload carrier mentioned in one of the ULA papers?
There is no need for heavy payloads to ISS. The truss is done. NASA doesn't have plans for anything big. Any "expansion" will be small or inflatable modules.
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#367
by
kevin-rf
on 14 Aug, 2010 17:31
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There are "supposed" to be 3 Delta-IV Heavies over the next twelve months. Looking through the currently posted launch manifest (on NSF) I don't see any additional Heavies. After the next three fly will it really be years before we see another heavy? Are there any announced Heavy contracts that have not been assigned a launch date?
I also noticed next up will sport the new RS-68a's. Is it really needed for the next flight, or is it being tested for a future flight that needs it?
Edit: Okay, feeling a bit sheepish, missed: 2015 - NRO L-37 - Delta IVH - TBD.
Meaning it will be fourish years before the next Heavy after this batch flys?
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#368
by
sdsds
on 14 Aug, 2010 23:07
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it will be fourish years before the next Heavy after this batch flys?
This speaks to the role EELV-Heavy plays in the overall DoD spacelift acquisition strategy. They only had a few missions in mind that could not be lifted by "standard" EELV-Medium vehicles. Rather than having a separate launch system specifically for these payloads, the EELV-Heavy approach using three "standard" EELV cores was (quite rightly) seen as cost effective,
especially because there are so few payloads in this class.
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#369
by
JosephB
on 07 Sep, 2010 15:10
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Will there be 2 versions of RS-68 going forward? (RS-68 & RS-68A)?
Or, are the 68A's the only kind being produced & when the old 68's are used up that's it?
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#370
by
kevin-rf
on 07 Sep, 2010 17:52
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Jim correct me if I am wrong, but didn't Boeing pre-ULA buy a large number of RS-68's that need to get used up before additional RS-68A production is needed? The only reason we have RS-68A's today is it was cheaper to do a batch of them than the other options available for increasing needed Delta IV Heavy performance.
Has ULA release the new RS-68A performance number for non heavy Delta IV's?
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#371
by
sdsds
on 07 Sep, 2010 22:16
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I would also appreciate correction if wrong, but isn't the expectation that once RS-68A flies successfully, all subsequent Delta flights will use RS-68A? (Perhaps there is a possibility that RS-68 inventory could be retrofitted?)
Further, RS-68A will allow a reduction in the number of different CBC variants, and some Delta vehicles will thus provide the same capability but in a different way, i.e. with a more efficient engine but also with a more massive CBC.
Fascinatingly, the February 9, 2010 press release from PWR that describes RS-68A status is no longer listed as being available from their archive. PRNewsWire has it here:
http://www.prnewswire.com/news-releases/pratt--whitney-rocketdyne-begins-certification-testing-of-the-rs-68a-rocket-engine-84050757.html
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#372
by
Antares
on 08 Sep, 2010 03:24
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#373
by
kevin-rf
on 08 Sep, 2010 14:17
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The ULA doc has the RS-68A integrated into the Delta IV M+(5,4) CCB in the 2014 time frame. So the answer is (if we can believe ULA and power point) is the RS-68A will replace the RS-68 and go to a single CCB design starting in 2014.
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#374
by
Robotbeat
on 24 Sep, 2010 20:27
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So, how will the HEFT study affect the Delta IV launch rate and price, especially for the Delta IV Heavy?
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#375
by
marsavian
on 24 Sep, 2010 20:32
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Currently the price is fixed ...
http://www.losangeles.af.mil/library/factsheets/factsheet.asp?id=5324Acquisition History
The initial phase of the EELV program, Low Cost Concept Validation (LCCV), was successfully completed in November 1996. LCCV emphasized competition in preliminary designs and risk reduction demonstrations. Four $30-million contracts were awarded during this phase to Alliant Techsystems, The Boeing Company, Lockheed Martin Corporation and McDonnell Douglas Aerospace. (Note: Boeing acquired McDonnell Douglas at about the time this competition ended.)
During the second phase, pre-engineering and manufacturing development, two $60-million, 17-month contracts were awarded to The Boeing Company and Lockheed Martin Corporation to continue refining their system concepts and complete a detailed system design.
EELV phase three began in October 1998 with the award of two development agreements and two initial launch services contracts (known as Buy 1) totaling more than $3 billion. The development agreements will run through fiscal year 2007 and the initial launch services contracts through fiscal year 2012. Additional launch service awards were made in Buy 2.
EELV Buy 3 is under negotiation. Buy 3 transitions the EELV contract from a commercial services contract to a hybrid of government contracts. The Buy 3 contracts consist of an EELV Launch Services (ELS) contract and an EELV Launch Capability (ELC) contract. The ELS is a firm fixed-price contract that buys the launch service to include mission hardware. The ELC is a combined firm fixed price/cost plus award fee contract that maintains workforce and facility readiness for mission success and provides the ability to deal with contingencies.
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#376
by
Robotbeat
on 24 Sep, 2010 20:42
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What does that mean? Does that really mean 10 Delta IV mediums a year will have the same price as 1? Don't you think ULA will charge more for just the one, since their fixed costs are very high (compared to marginal costs) if you only launch one a year?
Anyone?
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#377
by
marsavian
on 24 Sep, 2010 20:43
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The fixed (facility) costs are taken care of in the ELC contract.
edit: for clarity/specificity.
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#378
by
Robotbeat
on 24 Sep, 2010 20:52
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The fixed costs are taken care of in the ELC contract.
So... Only the marginal costs are paid for, then?
Is that the only way that NASA can acquire launch services for the Delta IV Heavy?
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#379
by
Will
on 24 Sep, 2010 21:07
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The fixed costs are taken care of in the ELC contract.
Is that strictly true? I thought that the DoD covered the fixed costs of the facilities, but that other customers picked up a share of the development costs.
That would also be a fixed cost, yes? If the company paid $1.5 billion to develop the launcher, and amortized them over, say, 20 years, then that would be $75 million a year, regardless of the number of flights. If you had two launches a year, that would be over $30 million a launch, if ten, $7.5