Author Topic: Griffin speech - Why one STS derived launch system would not work for Constellation  (Read 91611 times)

Offline Smatcha

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http://www.nasa.gov/pdf/208916main_Space_Transportation_Association_22_Jan_08.pdf


Everything up to the “However” on page 16 is excellent. The rational for the current 1.5 archeicture that follows though is exceedingly flawed.

First off starting, on page 15, I couldn’t agree more with this statement and its one the primary reasons the DIRECT concept is superior to the current plan.

Mike Griffin (pg15): “However, the decision to employ EOR in the lunar transportation architecture implies nothing about how the payload should be split. Indeed, the most obvious split involves launching two identical vehicles with approximately equal payloads, mating them in orbit, and proceeding to the Moon. When EOR was considered for Apollo, it was this method that was to be employed, and it offers several advantages. Non-recurring costs are lower because only one launch vehicle development is required, recurring costs are amortized over a larger number of flights of a single vehicle, and the knowledge of system reliability is enhanced by the more rapid accumulation of flight experience.”

This is where Mike goes off the rails.

Mike Griffin (pg16): “However, this architectural approach carries significant liabilities when we consider the broader requirements of the policy framework discussed earlier. As with the single-launch architecture, dual-launch EOR of identical vehicles is vastly over designed for ISS logistics. It is one thing to design a lunar transportation system and, if necessary, use it to service ISS while accepting some reduction in cost-effectiveness relative to a system optimized for LEO access. As noted earlier, such a plan backstops the requirement to sustain ISS without offering government competition in what we hope will prove to be a commercial market niche. But it is quite another thing to render government logistics support to ISS so expensive that the Station is immediately judged to be not worth the cost of its support. Dual launch EOR with vehicles of similar payload class does not meet the requirement to support the ISS in any sort of cost-effective manner.”

First off, however you want to measure it, the Jupiter-120 is far superior in terms of life cycle cost and implementation time to the Ares-I forgetting for a moment the serious engineering flaws that may or may not be solvable or programmatic problems outlined in the GAO report.
The fact that the Jupiter-120 has a capability far superior to the Ares-I, is a closer to match to the Space Shuttle, and is nearly 100% compatible with the current STS infrastructure is icing on the cake.

The whole notion that the Jupiter-120 is more expensive on a lifecycle basis is beyond belief. Care to take the OMB, GAO or CBO up on that assessment of Ares-I vs Jupiter-120 life cycle cost Mike?

The fact that we can also bring up an ISS logistics module along with the crew is not a problem in the pre-COTS ISS servicing time frame. Rather it is actually a significant cost advantage over Ares-I. In addition, we could actually finish the ISS with US taxpayer funded ISS elements to be put in warehouses under the current plan after the Space Shuttle’s retirement. Imagine that, NASA could actually finish what it started.

By the time the Jupiter-120 ISS missions could possibly overlap a viable COTS solution for ISS logistics and crew rotation support we should be moving on towards the Moon anyway. Along those lines the Jupiter-120 would move off of ISS support, leaving that role to COTS, and would be redirected at maturing key spacecraft systems just like Apollo did prior to the addition of the upper stage need for the Jupiter-232. Apollo-8 and Apollo-9 missions come to mind. The Jupiter-232 also has a single launch capability to both the Earth-Moon and Sun-Earth Lagrange points for the crew should those exploration Archeictures prove to be more cost effective in the long term.

Besides that the Jupiter-120’s superior volume and lift capacity creates a new intermediate class of launch systems between the EELV and Jupiter-2 series yet won’t require that the entire unmanned exploration budget over many years just to pay for the spacecraft an Ares-V could lift. It’s really volume improvement they are after anyway not the lift capacity.

I agree with this next statement.

Mike Griffin (pg16): “On the other end of the scale, we must judge any proposed architecture against the requirements for Mars. We aren’t going there now, but one day we will, and it will be within the expected operating lifetime of the system we are designing today. We know already that, when we go, we are going to need a Mars ship with a LEO mass equivalent of about a million pounds, give or take a bit. I’m trying for one-significant-digit accuracy here, but think “Space Station”, in terms of mass.

I hope we’re smart enough that we never again try to place such a large system in orbit by doing it in twenty-ton chunks. I think we all understand that fewer launches of larger payloads requiring less on-orbit integration are to be preferred. Thus, a vehicle in the Saturn V class –some 300,000 lbs in LEO – allows us to envision a Mars mission assembly sequence requiring some four to six launches, depending on the packaging efficiency we can attain. This is something we did once and can do again over the course of a few months, rather than many years, with the two heavy-lift pads available at KSC Complex 39.”

Now for the non-sequitur.

Mike Griffin (pg17): “But if we split the EOR lunar architecture into two equal but smaller vehicles, we will need ten or more launches to obtain the same Mars-bound payload in LEO, and that is without assuming any loss of packaging efficiency for the launch of smaller payloads. When we consider that maybe half the Mars mission mass in LEO is liquid hydrogen, and if we understand that the control of hydrogen boil off in space is one of the key limiting technologies for deep space exploration, the need to conduct fewer rather than more launches to LEO for early Mars missions becomes glaringly apparent.”

Whether we use 4 launches (Ares-V) or 5 launches (Jupiter-232) we are still going to need some means of storing cryogens over long durations and transferring them in space. The other limitation is on the Mars Entry Descent and Landing portion of the mission. What we can ultimately land on Mars in one piece will limit what we need to throw at Mars anyway.

All this not withstanding the Jupiter-244 can actually place more mass and the same volume into orbit as the Ares-V if that ever became a limitation which it most likely will not. Concerning packaging efficiency most of the mass we need in orbit is propellant and there aren’t better ways to package cryogens then we do now. A propellant depot is one of the key enabling technologies for Mars and our spacecraft will ultimately be limited by what we can land or afford which ever comes first.

And now for the crescendo of non-sequiturs;

Mike Griffin (pg17): “So if we want a lunar transportation architecture that looks back to the ISS LEO logistics requirement, and forward to the first Mars missions, it becomes apparent that the best approach is a dual-launch EOR mission, but with the total payload split unequally. The smaller launch vehicle puts a crew in LEO every time it flies, whether they are going to the ISS or to the Moon. The larger launch vehicle puts the lunar (or, later, Mars) cargo in orbit. After rendezvous and docking, they are off to their final destination.”

Actually the only thing that is really apparent after working thru the logistics issues of an expansive Lunar and Mars exploration program is that we should place all the propellant in orbit first followed by the entire time sensitive and extremely expensive mission package of a dry spacecraft with crew. By tanking up the spacecraft and Earth departure stage in space and we can do just about anything using this approach over the long haul.

Of course Wernher Von Braun figured this out a long long time ago lest we forget.
Concluding remarks by Dr. Wernher Von Braun about the Mode Selection for the Lunar Landing Program given to Dr Joseph F. Shea, Deputy Director (Systems) Office of Manned Space Flight, June 7, 1962

“Let me point out again that we at the Marshall Space Flight Center consider the Earth Orbit Rendezvous Mode entirely feasible. Specifically, we found the Tanking Mode substantially superior to the Connecting Mode. Compared to the Lunar Orbit Rendezvous Mode, it even seems to offer a somewhat greater performance margin. This is true even if only the nominal two C-5’s (tanker and manned lunar vehicle) are involved, but the performance margin could be further enlarged almost indefinitely by the use of additional tankers.”

Beyond logistics are two other key aspects of the VSE, that being International participation and COTS. By opening up the delivery of propellant to depot in Earth orbit to COTS we have placed over 80% of the mass we need in orbit for VSE into the private sector. In addition because we separated the expensive spacecraft and critical crew delivery requirements, more cost effective approaches of delivering payload to orbit could be used because the manufacturing cost of propellant is orders of magnitude cheaper than anything else we place in space.

International participation in an American lead VSE is also enabled as long as they place their share of the propellant using their nation’s launch system.

I have to thank Mike though in put together in a very well written and concise way (pages 1 to15) all the ways that DIRECT actually fulfills every single letter of the VSE policy directive in direct contrast to the current plan that violates nearly every requirement.

“Do we want to go to the moon or not?”
John C. Houbolt - November 15, 1961
Question posed in Letter to Dr. Robert C. Seamans Jr, NASA Associate Administrator

Ralph Ellison “I was never more hated than when I tried to be honest”




Offline Jorge

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This needs to be merged with the other thread...
JRF

Offline Smatcha

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Jorge - 23/1/2008  1:04 PM

This needs to be merged with the other thread...

Already talked to Chris about the split.  Mike made a number of bad assertions.  This thread deals with just one of many.  Besides the EELV and the one STS derivative there are a few more but I don’t have time for those.

“Do we want to go to the moon or not?”
John C. Houbolt - November 15, 1961
Question posed in Letter to Dr. Robert C. Seamans Jr, NASA Associate Administrator

Ralph Ellison “I was never more hated than when I tried to be honest”




Offline Smatcha

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More follow-up;

(Mike page 16) “However, this architectural approach carries significant liabilities when we consider the broader requirements of the policy framework discussed earlier.  As with the single-launch architecture, dual-launch EOR of identical vehicles is vastly over designed for ISS logistics.”

While I would grant you that the Ares-V is significantly over designed for ISS logistics, the Jupiter-120 has a nice but not over reaching margin over the Ares-I allowing both crew rotation and ISS logistic support in the same launch.  At the same time, and in direct contrast to the Ares-I I might add, the Jupiter-120 offers the Orion team the mass margin they need to get all the systems out of the parking lot and into orbit for your once in a generation spacecraft you talk so much about.

In addition, because the Jupiter-120 doesn’t need an expensive upper stage, unlike the Ares-I and Ares-V, uses existing engines (big time saver safety tip you might look into that one if you are hard up for cash and time), uses the existing 4-Seg SRB design and STS stack configuration (a proven way to deal with SRB vibrations), that uses the existing manufacturing, integration and launch infrastructure the Jupiter-120 is actually less expensive from a life cycle cost standpoint over the period of time we may need to support ISS with it.

(Mike page 16) “It is one thing to design a lunar transportation system and, if necessary, use it to service ISS while accepting some reduction in cost-effectiveness relative to a system optimized for LEO access.”

Again this whole statement is absolutely positively false.  Care to have the GAO, OMB or CBO (your pick) take a look to see if in fact the Ares-I is even close to the Jupiter-120 let alone less expensive on any time horizon you choose 5,10,15,20 years (take your pick again)?

(Mike page 16) “As noted earlier, such a plan backstops the requirement to sustain ISS without offering government competition in what we hope will prove to be a commercial market niche.  But it is quite another thing to render government logistics support to ISS so expensive that the Station is immediately judged to be not worth the cost of its support.”

Which one is it Mike does the Jupiter-120 compete with COTS or is it too expensive?  We already know that the more expensive part vs Ares-I is false so I’ll just focus on the unfair competition with COTS.  I would agree that if the Jupiter-120 has any ‘problems’ it’s that it could actually be ‘more’ cost effective on a variable unit launch cost basis than COTS because it has an ‘unfair’ advantage of utilizing all those billions in STS manufacturing, integration and launch infrastructure the tax payer has already paid for.  You know all the same stuff you want destroy and then recreate in your own image requiring still more taxpayer dollars.  Oh I get it now.  All this expense and time delay you want to heap on the taxpayer for Ares-I is just so NASA can make it fair for the poor COTS guys.  Give them a fighting chance against the deep pocket government.  Sorry my misunderstanding.

See the thing is you don’t need to do that for the Jupiter-120 and you are partly to responsible for taking away this little too cost effective vs. COTS problem off the table.  See thanks in large part to what will become known in the near future as the ‘Ares-I/V debacle or Griffin Folly’ ,take your pick its your baby you've earned it, in order to recover from this mess ‘we’ (meaning the ones whose laps this debacle will ultimately drop into) will need to execute a near standing start of the Jupiter-120 circa FY2010 assuming you hang on to the bloody end.  Even with so much of the infrastructure and hardware systems already in place for the Jupiter-120 both EELV and COTS will be in better position to support the ISS anyway in the 2010-2014 timeframe so the Jupiter-120 will be a developmental point for the Jupiter-232.

That’s provided NASA doesn’t require the EELV or COTS guys to muck up a perfectly good launch systems for man-rating requirements that even the Ares-I routinely gets a pass on.  I’m pretty sure that causing severe brain damage to the astronauts or allowing even minor shear winds on ascent to bend the Ares-I in half at the interstage doesn’t fit the ‘spirit’ of NASA man rating requirements.

All attempts to solve this via damping, mass or elfin magic will cause one or the other of these interrelated yet oppositely driven problems to occur so take your pick of disaster because you have to choose one or the other.  It’s amazing really, the depth to which group think coupled with authoritarian rule can drive any organization into the ground in such a short time.  But enough on the dangers of Communism.

Back in America (where free thought and interchange should be the rule and not the exception, I vaguely remember US Constitution mentioning something along these lines) we are right now on a path, after waiting more than twenty five years mind you, towards designing an American launch system that is even more expensive, more dangerous, less efficient, and less capable than the current Space Shuttle.  No small accomplishment in such a short fun filled two years since ESAS came out.

(Mike page 16) “Dual launch EOR with vehicles of similar payload class does not meet the requirement to support the ISS in any sort of cost-effective manner.”

Again you have a standing invitation to prove this using any of the available government agencies that actual do these kind of evaluations day in and day out for a living.  They even cover the printing cost of the report.


“Do we want to go to the moon or not?”
John C. Houbolt - November 15, 1961
Question posed in Letter to Dr. Robert C. Seamans Jr, NASA Associate Administrator

Ralph Ellison “I was never more hated than when I tried to be honest”




Offline rsp1202

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Griffin should be called on every one of the points you've made. The fact that he's addressing some of the concerns at all means he's feeling some heat. (Shoot, even Hirohito had to come out of the palace eventually and admit, yep, there's some bombing going on.) Keep it up.

Offline Yegor

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If to switch to DIRECT.
Will it be possible to develop a hydrogen LEO storage solution for 15 billion savings on Ares I and Ares V development plus 900 million a year on operations?


Offline jongoff

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Yegor - 23/1/2008  7:57 PM

If to switch to DIRECT.
Will it be possible to develop a hydrogen LEO storage solution for 15 billion savings on Ares I and Ares V development plus 900 million a year on operations?

Yes.  Quite frankly, NASA could get that capability for less than $1B if they could find a way to put that money in escrow to purchase the first 100,000 of LOX/LH2 from a commercial depot.

~jon

Offline Yegor

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“If you are trying to catch two hares at the same time you will catch none.” (Russian proverb)

NASA is trying to catch three hares ISS, Moon and Mars.
May be left with none. ISS has its life limit too.


Offline kkattula2

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jongoff - 24/1/2008  3:20 PM

Quote
Yegor - 23/1/2008  7:57 PM

If to switch to DIRECT.
Will it be possible to develop a hydrogen LEO storage solution for 15 billion savings on Ares I and Ares V development plus 900 million a year on operations?

Yes.  Quite frankly, NASA could get that capability for less than $1B if they could find a way to put that money in escrow to purchase the first 100,000 of LOX/LH2 from a commercial depot.

~jon

As I understand it. Liquid Oxygen would be by far the largest component by mass of any non-nuclear Mars mission. A far easier depot problem. Liquid Hydrogen would be the largest volume, but one Ares V or Jupiter 232 would suffice to launch that mass: < 80 mt

Offline kkattula2

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From the ESAS document:

"To meet the CEV lift requirement, the team initially focused on five-segment RSRB-based solutions. Three classes of upper stage engine were assessed-SSME, a single J-2S+, and a four-engine cluster of a new expander cycle engine in the 85,000-lbf vacuum thrust
class. However, the five-segment development added significant near-term cost and risk and the J-2S+/expander engine could not meet the 2011 schedule target. Therefore, the team sought to develop options that could meet the lift requirement using a four-segment RSRB. To achieve this, a 500,000-lbf vacuum thrust class propulsion system is required. Two types of upper stage engine were assessed-a two-engine J-2S cluster and a single SSME. The J-2S option could not meet the 2011 target (whereas the SSME could) and had 6 percent less performance than the SSME-based option (LV 13.1). The SSME option offered the added advantages of an extensive and successful flight history and direct extensibility to the CaLV with no gap between the current Shuttle program and exploration launch. Past studies have shown that the SSME can be altitude-started, with an appropriate development and test
program."

So NASA has fallen back to an option that they themselves categorized as; more risk, more cost, lower performance and longer development time. Yet there are clearly options that are; less risk, less cost, much more performance and shorter development time.

It's not rocket science guys...err...


Offline jongoff

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Kkatula2,
Quote
As I understand it. Liquid Oxygen would be by far the largest component by mass of any non-nuclear Mars mission. A far easier depot problem. Liquid Hydrogen would be the largest volume, but one Ares V or Jupiter 232 would suffice to launch that mass: < 80 mt

While it's true that LOX is most of the propellant, it really isn't that much easier than LH2.  Once you know how to handle LOX without boiloff, you're most of the way there to having a good LH2 system as well.  And the big selling point of having the ability to store LH2 as well as LOX is that now you *don't need* Ares V or Jupiter 232.  You can launch your big pieces on stock Atlas or Delta or Falcon vehicles, and your propellant gets shipped up by whoever has the best prices.  At the demand rate that even 2-3 missions a year would produce, you'd be talking about somewhere around half a million pounds of propellant in orbit.  That's enough propellant that you could close a business case for developing an RLV to service it.  While there are technical challenges with RLVs, the biggest challenge is getting over the funding hurtle.  The question Jim likes asking is "where's the payloads".  If you need 500,000lb of a commodity that can be shipped in chunks as small as 1000lb, you have your payloads there--and plenty of them.  

So when people get all indignant at "but if you don't have heavy lift, you'd need 6-8 EELV flights for all the propellant", I chuckle a little bit--because what I'd like to see is something more like 20-30 flights of a small (~1-2.5tonne to LEO) RLV fleet over the course of a few weeks.  But saying that would likely make some people's heads explode.

~Jon

Offline kkattula2

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That's true, but storing just one propellant, long term, might simplify depot design.  

On the other hand, 2 time critical launches would be required for a Mars mission, crew and LH2 instead of just crew.  

On the gripping hand, LH2 boil-off would need to be solved for the journey itself, unless 'storable' fuels were used for everything after the TMI.

Offline kkattula2

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I don't know how Mike can keep a straight face when he mentions the Congressional requirement to maximize use of existing Shuttle hardware and facilities.  He's changing the engines, the SRB's, the tankage, the VAB and the MLP. Not much is being retained.

Direct would keep the same SRB's, 70% the same ET, and require far fewer changes to all the others.

I'm starting to think Mike is being fed limited info about Direct. Maybe just the cost & performance figures of one of the lesser J-2's?
Otherwise I can't see how he would think that J-120 is such overkill for ISS, yet 2 x J232's are not enough for Moon & Mars exploration.
It's like he doesn't realize the Upper Stage is optional and not required until later in the program.

Offline khallow

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SMetch - 23/1/2008  12:45 PM

I hope we’re smart enough that we never again try to place such a large system in orbit by doing it in twenty-ton chunks. I think we all understand that fewer launches of larger payloads requiring less on-orbit integration are to be preferred. Thus, a vehicle in the Saturn V class –some 300,000 lbs in LEO – allows us to envision a Mars mission assembly sequence requiring some four to six launches, depending on the packaging efficiency we can attain. This is something we did once and can do again over the course of a few months, rather than many years, with the two heavy-lift pads available at KSC Complex 39.”

Perhaps it's just due to my EELV fetish, but why is putting something large in orbit 20 tons at a time a bad idea? What am I missing?

Added: I guess what I'm puzzled by is how would the Shuttle and ISS observations indicate that assembly in such a manner is a problem?
Karl Hallowell

Offline kraisee

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I have spent considerable time reading and absorbing Dr. Michael D. Griffin's Remarks to the Space Transportation Association (STA) from Tuesday 22nd January 2008.   I decided to wait and mull the remarks fully until I could put together a suitable and considered reply.

I haven't yet read any of the other feedback here on the site as I write this, so I apologise if I cover ground already well-trod.   But as a leading representative of one of the teams who has placed itself in direct opposition to certain parts of the existing architecture, this is the first draft of an open letter which I intend to send to Michael Griffin.   I would appreciate constructive comments from the members of the forum.

Dear Dr. Michael D. Griffin and the staff of the Constellation Program,
I would firstly like to say a big thank-you to Dr. Griffin for his recent remarks to the Space Transportation Association (STA) from Tuesday 22nd January 2008 .   I can say, hand-on-heart, that I agree strongly with about three-quarters of his speech.   While I may disagree with the remaining quarter, he makes many excellent arguments and provides extremely valuable insight to everyone into the process behind architecture selections in a program like this.

In particular, I concur with the general assessment that the US needs to rebuild its lost heavy lift launch capabilities we short-sightedly discarded in the 1970's.    If we are ever to go to the moon in a truly efficient manner and, more importantly, if we are ever to attempt to expand out towards Mars and other worlds beyond, we need the ability to launch the vast bulk of hardware and resources which will be needed to establish a long-lasting space infrastructure throughout the 21st Century.

Dr. Griffin explains, in truly wonderful detail, the underlying requirements and reasoning which formed both the CAIB findings and the Congressional National Aeronautics and Space Administration (NASA) Authorization Act of 2005.   This STA presentation makes for a very powerful and compelling read to anyone wishing to understand the background to NASA's new endeavors.

Obviously, I do have some differences of opinion regarding some specific choices which have been made so far in the specific field of launchers, which I will try to explain and compare in detail below.   But I wish it to be very clear that I mostly agree with Dr. Griffin, and Congress, regarding the larger focus of the Vision For Space Exploration.

I agree that the Orion Crew Exploration Vehicle (CEV) is the best near-term approach for NASA to primarily support the Lunar program, but also to support the existing International Space Station while commercial operations continue to mature their alternatives for LEO access for both cargo, and later crews.

I also agree that the Altair Lunar Surface Access Module (LSAM) concept is the best general approach as an early-generation Lunar Lander for both Crew and Cargo use.   It builds on valuable lessons learned during the amazing Apollo missions, while expanding the capabilities to a whole new level.   It also offers an exceptionally robust concept upon which to build enhanced developments over many years into the future.

I further concur with Congress, that getting ISS operational with a minimum crew of six is essential for both scientific and political reasons, and that retiring the venerable Space Shuttle in 2010 when ISS is ready, is the best plan to allow us to fund the new program fully.   I completely agree that we need a replacement for Shuttle, to launch the CEV operationally by no later than 2014 too.   And that we need a heavy lift launcher for the large missions to the moon and Mars.   Dr. Griffin points out many reasons behind the excellent logic of reusing existing Shuttle technology and hardware for the new launchers, as it benefits cost, schedule and the current workforce - a move which preserves all of the valuable knowledge gained over the past 25 years of that complex program.

While I have previously been a vocal and sometimes bitter critic of both Dr. Griffin and also of the current plans to build the two Ares launch vehicles, I wish my disagreements to be seen in the correct context - alongside the many elements I do agree with in the larger theater of the plans for the Vision for Space Exploration.   Amazing as it may be to some, Dr. Griffin and I actually share many identical views on many of the basic elements of the new program.   While there has been vitriol aplenty, I actually find I support NASA's Administrator far more than I oppose him.


Having outlined many of the elements which I do agree with, I will now concentrate on the specific subjects where I have a difference of opinion and will attempt to carefully explain the different thought processes behind them in the context of Dr. Griffin's remarks.

Dr. Griffin correctly states "Any system architecture must be evaluated first against the tasks which it is supposed to accomplish. Only afterwards can we consider whether it accomplishes them efficiently, or presents other advantages which distinguish it from competing choices."   He goes on to detail the specifics of Presidential policy and Congressional direction, which I will refrain from repeating here in the interests of brevity, but this is excellent reasoning which I would like to make clear forms the backbone of thinking behind the alternative architecture we have proposed in the DIRECT Team, not just the ESAS approach.   The two approaches stem from very common ground.


From within the NASA Authorization Act of 2005, Griffin quotes the following: "The Administrator shall, to the fullest extent possible consistent with a successful development program, use the personnel, capabilities, assets, and infrastructure of the Space Shuttle program in developing the Crew Exploration Vehicle, Crew Launch Vehicle, and a heavy-lift launch vehicle."   We agree with this completely.   However we suggest a different approach to executing it compared to NASA currently.   While NASA has interpreted this "...Crew Launch Vehicle, and a heavy-lift launch vehicle" instruction to mean two separate vehicles, we have interpreted it differently - to mean a single vehicle capable of flying in two different configurations capable of performing the two different duties.   This is a fundamental, but subtle, difference in execution which has quite different results - although both can achieve the targets.   I will attempt below, to detail why the "one-vehicle, two-configurations" method would offer NASA significant advantages over the "two-vehicle" approach.


Dr. Griffin continues "Finally, the new architecture must take advantage of existing Space Shuttle program assets "to the fullest extent possible"."   We have made the conscious effort to take this very literally with DIRECT, in that we are deliberately attempting to re-use the maximum possible amount of current Shuttle manufacturing, launch processing infrastructure and flight hardware that we can, with the least amount of new development, cost or new technology delaying the schedule, whilst also achieving all of the objectives and requirements of the three missions: ISS, Lunar and Mars programs.   NASA has taken the different approach of using existing Shuttle manufacturing, launch processing infrastructure and flight hardware as a 'point of departure' to create two new vehicles which ultimately have very little real commonality to anything in the existing Shuttle infrastructure today.

Let me spend a moment here to compare all of these systems from this perspective.

ESAS Ares-I and Ares-V:

While visibly similar, the Ares-I SRB's are being considerably changed in form, function and performance.   The only common element will be the white cylindrical steel cases.   All other elements, from parachutes to Aft Skirt, Nozzle to Thrust Vectoring System, Separation Systems to Recovery Parachutes - all are being replaced with brand new items custom-designed and manufactured for the new configuration.

Similarly, while covered with the same orange foam and while fabricated from the same Aluminum-Lithium alloys, neither the 5.5m diameter Ares-I Upper Stage, nor the 10m diameter Ares-V Core Stage or the 10m diameter Ares-V Upper Stage will be manufactured on the same fabrication hardware as the 8.4m diameter Space Shuttle External Tanks are today.   The existing manufacturing equipment is mostly being mothballed.

Ares-V requires an engine which does not currently fly yet - an upgraded and human-rated version of the RS-68 used by the USAF Delta-IV program, but a '106%' version with improved performance from that flown today.

Both Ares-I and Ares-V will also need an all-new engine, the J-2X.   While visibly bearing a resemblance to its predecessor, the Apollo J-2, the J-2X will essentially be an all-new engine.   It is being designed using new techniques, will be built on brand-new manufacturing equipment because the original manufacturing facilities have not existed in more than 30 years and is being re-designed to be 27% higher performance.   Additional scheduling pressure is created because this engine must be ready as soon as possible as it is the crucial element determining the Ares-I schedule to 'close the 'gap' after Shuttle retires.

Ares-V then requires an additional stage too, the Earth Departure Stage (EDS) which will use very similar J-2X engines for power.

Additionally, neither Ares vehicle is planned to utilize much of the existing infrastructure elements from Shuttle - what isn't to be replaced, is to be heavily re-worked.   The Ares-I requires two all-new Mobile Launcher's (ML) with an all-new launch tower on each.   Additional considerable changes are then required at both of the Kennedy Space Center's launch pads and inside the cavernous VAB to support Ares-I also.   After that, the Ares-V will require complete re-building of the existing three Space Shuttle Mobile Launcher Platforms (MLP), with three more massive new launch towers on each, and yet more alterations to the VAB.


DIRECT Jupiter:

Compare that extensive list of changes to the single-vehicle solution which DIRECT proposes.

The Jupiter launch systems propose to retain the existing 4-segment SRB's from Shuttle completely unmodified.   No new Segments, Nozzle, TVC, Separation Systems, Parachutes, Aft Skirt or any other hardware needs replacing.   The existing systems are more than adequate already and have more than thirty years of life in them still.

The Core vehicle will be manufactured on precisely the same equipment used today to turn out External Tanks (ET) for Shuttle.   Fundamentally, the tanking sections of Jupiter bear a great deal in common with ET, although are manufactured stronger.  Extra production line facilities are needed to prepare the unique parts for the different in-line stage arrangement, but these represent approximately 25% of the total stage, compared to ET.   There is sufficient in-common with ET that theoretically, many of Jupiter's Core Stage elements could be made in parallel at the same time as Shuttle ET's, using the same equipment and personnel.

Like Ares-V, the Jupiter also uses the RS-68 from Delta-IV - but does not require the higher performance variant.   It can certainly benefit from additional performance if the USAF does complete their upgrade program as planned by 2012, but Jupiter does not require that additional performance in order to meet all of its performance targets for all ISS, Lunar and Mars missions.   Should the upgrade be canceled by USAF for any reason before completion, it would not be a crippling performance blow to the Jupiter systems.

Then, only limited changes are required to the three current Shuttle MLP's to support Jupiter launches - they will not a complete re-build as Ares-V needs because the Shuttle and Jupiter systems both share a common basic 'footprint' thanks to using the identical 8.4m diameter Core Stage/ET.   To support Jupiter, more than 75% of the existing support hardware inside the VAB processing Shuttle's today can be retained without change.   The other 25% require only relatively minor modification compared to either Ares vehicle.   The KSC pad modifications are also limited to alterations only - not complete replacement - of the existing two fixed launch towers in place currently.   The Jupiter system certainly does not require two new ML's and five new launch towers.

Jupiter will need the J-2X engine for its similar EDS to Ares-V's - although this stage is optional for Jupiter and is not required at all in order to 'close the gap' after Shuttle - it is only required for the later Lunar mission phases when real heavy lift becomes a necessity.   Without this EDS, the base Jupiter vehicle, called "Jupiter-120", is a 50-ton to LEO launch system.   Adding the EDS and one extra main engine (All Jupiter Core's are designed to fit up to three RS-68's and engines are essentially considered 'bolt-on' items when necessary) the larger "Jupiter-232" system increases the same basic vehicle's capability to more than 100-tons.   The development schedule for J-2X on Jupiter is also less taxing - it can take 2 extra years - and delivery date of the J-2X has no impact at all for 'closing the gap' after Shuttle - the engine and its EDS are simply not utilized at all on the smaller Jupiter-120 configuration used initially to service the ISS from 2012 thru 2016.   The EDS is only required in 2017 to begin Lunar exploration missions - And Jupiter-232 will be ready to do that 2 years sooner than Ares-V will be.


What these differences all boil-down to is that the one-vehicle Jupiter solution can accomplish all of the same requirements as Ares-I and Ares-V together - and actually offers potentially useful additional performance capabilities for both ISS and Lunar missions at the same time - without compromising Mars performance later.


Dr. Griffin very graciously confirms that when "launching two identical vehicles... ...Non-recurring costs are lower because only one launch vehicle development is required, recurring costs are amortized over a larger number of flights of a single vehicle, and the knowledge of system reliability is enhanced by the more rapid accumulation of flight experience."

This is 100% correct. But the precise use of this argument in his remarks does not consider that the "two identical vehicles" might possibly be designed in such a way to have the option of flying in a different configuration using the same hardware.

Dr. Griffin states that the "two identical vehicles... ...approach carries significant liabilities when we consider the broader requirements of the policy framework discussed earlier. As with the single-launch architecture, dual-launch EOR of identical vehicles is vastly overdesigned for ISS logistics."   This is certainly very true in the majority of cases.   But in the specific case of the Jupiter launcher, the large Jupiter-232 configuration vehicle used for 2-launch Lunar missions can 'become' the much smaller Jupiter-120 vehicle for ISS missions by simply removing the EDS Upper Stage element and one Core Stage main engine.   Remember that this turns the 100-ton Lunar launch system into a 50-ton launch system, and that smaller and simpler system has flight costs very similar to Ares-I.

This is a particular circumstance where the assumptions made in order to create the ESAS recommendations have a significant and critical hole in them.

The Jupiter launcher is designed from the start to be a 100-ton heavy lift launch vehicle suitable for accomplishing the Lunar and Mars objectives of the new program - it is effectively a slightly smaller and considerably cheaper 'Ares-V'.   But instead of also developing Ares-I to handle the separate mission requirement of a pure Crew Launch Vehicle, the same Jupiter launcher can also fly in a much smaller configuration and perform all of the duties of Ares-I - and actually offers 25-tons of additional payload capacity which can be utilized in the future as NASA needs.

This unique approach was simply never assessed by ESAS.   It simply slipped through the cracks.   This approach does, however, offer some major advantages over the two-vehicle approach in place right now so needs to be re-examined as soon as possible to ensure NASA is not missing a valuable opportunity to gain ground.   Let me reiterate some of the more significant points:-

1) For Lunar missions, 2 x Jupiter-232 performance is 120% of 1 x Ares-I + 1 x Ares-V.

2) Lunar missions can begin 2 years earlier (dependent entirely on LSAM schedule) with 2 x Jupiter-232 than with 1 x Ares-I + 1 x Ares-V.

3) For ISS missions, 1 x Jupiter-120 ISS performance is >200% greater than 1 x Ares-I.

4) Jupiter-120 can be operational in mid-2012 because of its less demanding technical development requirements.   Ares-I is currently slated to miss the Presidential dictate of 2014, with a first crew flight currently due March 2015.

5) Currently, with Ares-I's official Loss Of Crew (LOC) safety assessment down to 1 in 1256, Jupiter-120's analysis indicates it is 12.5% higher safety at 1 in 1413 LOC.

6) Ares-V does not achieve the minimum crew safety requirements of 1 in 1000 LOC as defined by the ESAS Report.   Jupiter-232 exceeds this minimum requirement by 12%, so can be flown with humans as a Crew Launch Vehicle.

7) "Full Wrap" Non-recurring Development cost for Ares-I + Ares-V is $30-35bn.   Jupiter-120 + 232 is $12-16bn.

8) Near-term Non-recurring Jupiter-120 Development costs to 'close the gap' are considerably reduced by deleting the requirement for any new SRB's and associated motors, nor requiring the new J-2X engine and an all-new Upper Stage with no heritage at all.   The existing RS-68 only requires human-rating, and the development cost of a Jupiter Core Stage is actually less expensive than the Ares-I Upper Stage because of such direct commonality with Shuttle's External Tank.   Some recent estimates suggest Jupiter-120 could be operational in 2012 for a DDT&E cost just 55% that of Ares-I due to fly in 2015.

9) A nominal >500-ton Mars mission will require the same number of launches with either system:-
   5 launches = 4 x Ares-V + 1 x Ares-I, or
   5 launches = 5 x Jupiter-232 (one w/ crew)


We therefore believe that ESAS missed a 'diamond in the rough' which needs to be re-considered afresh.

We believe this alternative approach offers advantages in performance, safety, schedule, workforce retention and both non-recurring and recurring cost.

We are convinced this concept, which has its roots already firmly within NASA's archives (National Launch System and ESAS LV-24/25) would allow NASA a much wider range of opportunities by reducing LV costs and allowing that money to be better spent on missions and additional infrastructure elements to the benefit of the greater VSE.


Towards the end of his remarks Dr. Griffin makes a point of saying "we are resolved to listen carefully and respectfully to any technical concern or suggestion which is respectfully expressed, and to evaluate on their merits any new ideas brought to us. We are doing that, every day. We will continue to do it."   In that same spirit, I deliberately leave all of my vitriol checked at the door.   I respectfully bring a concept to NASA's table and I request you and your team take some time to examine the underlying ideas, the principles behind DIRECT's Jupiter launchers.   I don't want you to take our word for anything.   I am not after a mere assessment of the presented numbers - but a reasoned look at the core of the approach instead - and from there allow your team to consider some of the many variations upon this theme.

The key guiding light, I feel, is this:  'One vehicle designed primarily for optimum Lunar performance, but based as closely as possible on the existing Shuttle Stack in order to keep development costs down, with an optional Upper Stage which can be removed to allow some variety of configurations and performance from the exact same hardware'.

I request you allow your team of talented engineers an opportunity to see what the basic idea is actually capable of when placed in their hands and fully investigated.   I have been personally amazed at the versatility of the system and would hope you and your team will allow the idea the chance I believe it deserves.   I firmly believe that you will be able to come up with far better results than our small team has so far with this outline.

I place the concept in NASA's hands and look forward to reviewing what I hope will be an open assessment of its merits.

Regards,

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

Offline PeteJ

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Excellent job Ross as always,

A few observations for you to consider.

1) You have done an excellent job of keeping numbers out of the debate and focusing on the principles, therefore would point 7 in your summary be better described as a percentage saving rather than quote the raw figures.

2) You have concentrated on the two launch vehicles Jupiter 120 and Jupiter 232, what you are actually advocating is an architecture to build a wide range of launch vehicles up to Jupiter 244, and NASA has to work out which to develop depending on it's needs, this demonstrates the flexibility to adapt to future requirements.

3) You have alluded to the pedigree of this concept with reference to NLS, but could you comment that this development of the concept has been done with the help of NASA staff, in order to confirm that NASA are the owners of this, would this help ?

Thanks

Pete

Offline William Barton

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khallow - 24/1/2008  4:33 AM

Quote
SMetch - 23/1/2008  12:45 PM

I hope we’re smart enough that we never again try to place such a large system in orbit by doing it in twenty-ton chunks. I think we all understand that fewer launches of larger payloads requiring less on-orbit integration are to be preferred. Thus, a vehicle in the Saturn V class –some 300,000 lbs in LEO – allows us to envision a Mars mission assembly sequence requiring some four to six launches, depending on the packaging efficiency we can attain. This is something we did once and can do again over the course of a few months, rather than many years, with the two heavy-lift pads available at KSC Complex 39.”

Perhaps it's just due to my EELV fetish, but why is putting something large in orbit 20 tons at a time a bad idea? What am I missing?

Added: I guess what I'm puzzled by is how would the Shuttle and ISS observations indicate that assembly in such a manner is a problem?

Just to satisfy my curiosity, where do you think the point of diminishing returns is for shipping up pieces and parts (and loads of fuel)? I think the main objection to assembling any large structure in orbit in 20mT chunks is, it has taken more than 10 years to assemble ISS that way, using a mixture of STS, Proton, and Soyuz/Progress launches. A secondary objection is infrastructure cost. The advantage of EELV is, they and their infrastructure already exist. The disadvantage is, infrastructure imposes limits. 500mT to LEO consumes 25 EELV launches, which is about the infrastructure limit for one EELV type for a year (one launch every two weeks). That imposes a robustness limit for the program, whatever it might be. To me, the EELV/20mT high flight rate paradigm points straight at making a true RLV development program worthwhile. Politics made our first attempt at that into STS.

Offline Yegor

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I just want to say thank you to Michael D. Griffin for addressing the inquiries concerning various aspects of NASA’s post-Shuttle spaceflight architecture!
Thank you Michael D. Griffin!

Definitely it is very useful because the silence that existed in this area was damaging NASA reputation.


Offline jongoff

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William,
Quote
500mT to LEO consumes 25 EELV launches, which is about the infrastructure limit for one EELV type for a year (one launch every two weeks). That imposes a robustness limit for the program, whatever it might be. To me, the EELV/20mT high flight rate paradigm points straight at making a true RLV development program worthwhile. Politics made our first attempt at that into STS.

And to me that last bit is precisely why I prefer an EELV based architecture.  Sure, you still use the EELVs for launching the hardware part of things, but if the demand for propellants, people, and light cargo is high enough to strain the EELV flight infrastructure, it's also more than high enough to provide a large enough market to close the business case for RLVs (probably more than one).  Right now, all RLVs can point to as *existing* markets are a couple of people to ISS per year, and a couple of small LEO sats.  Nowhere near the numbers that are needed for an RLV to really make a dent in the launch price.  There are some potential markets that should improve things--ie if Bigelow pulls off his station, and if he's able to get the kind of customer interest he's banking on, that would be almost 100 passengers per year.  For a smaller RLV (pilot plus two passengers) that might be enough to start making things interesting.  But if you have 100-250 tonnes of propellant needed on orbit every year, that's *definitely* big enough, and big enough for multiple providers.

DIRECT is never going to be able to handle more than 12-16 people out of LEO in a given year.  An RLV based commercial architecture could potentially be a *lot* more capable once it gets going.  And even if it takes the RLVs a while to come on-line, EELVs aren't *that* bad when bought in large numbers.

~Jon

Offline clongton

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Jon,
DIRECT isn’t supposed to handle much more than 12-16 people out of LEO per year. That’s not its mission. It is not designed to be a people carrier. Because NASA has decided to use a SDLV architecture, DIRECT’s mission is to get the best bang for the buck from that architecture that we can, not to try to prove that the EELV/RLV architectures couldn’t do the same job. You’ve seen me state over and over again that as long as we must use a SDLV, that it has to be done in concert with a wise use of the existing capabilities. I don’t want to cut the EELV and potential RLVs from the picture. I want to use them as much as possible. I want to bring the flight rate up as high as we can, as much as the SDLV architecture will allow. I want to see People shuttles going back and forth to LEO on EELV-class commercial launchers. I want to see propellant depots in space being operated by commercial entities. DIRECT is not designed to eliminate EELVs or RLVs. It’s designed to eliminate Ares. We’re just trying to get the best value we can for the path Griffin has put us all on, that’s all. Griffin put us all on the path that eliminates the EELV from consideration, not us, and then he clamped down on the release of any information that could serve to challenge the correctness of his decision. What the DIRECT people did was, not agree with his decision, but to survey the landscape he put us on and to try to get the most from it that we could. It wasn’t that hard to show that Ares was not the best SDLV solution, so we provided a different one, but still STS based, in the hope that he would adopt it, instead of Ares. With Ares, the EELV class of launcher won’t get much use in the VSE and propellant depots will remain tomorrow’s technology for a long time. With the DIRECT architecture, use of the EELV will be maximized as much as possible and propellant depots will be brought online fairly quickly, specifically to allow the EELV to participate much more in the VSE. Of course, the Jupiter would benefit from the depot as well, but hey – spread the wealth.
Chuck - DIRECT co-founder
I started my career on the Saturn-V F-1A engine

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