Again how do you do .5 a launch???
Quote from: HIP2BSQRE on 01/05/2013 04:15 amAgain how do you do .5 a launch???Assuming you are not being tongue-in-cheek (I know perhaps you are ), it's more like the show Two and a Half Men, just a metaphor for two full sized men and a third (half grown male) who's not as large. You have two rockets, one really large and the other about 0.5 times the size of the first (though still huge). It's the architecture that is 1.5, not the number of launches. Some might see it like a bad joke: sending up one and a half rockets in two launches.Following STS-107, Griffin felt strongly (some would say obsessively) about sending up most of the cargo on a mega CLV (cargo launch vehicle), then sending the crew on a smaller LV with as little propellant and as little hardware as possible other than their capsule, so that the crew launch would be as safe as possible. Many felt using a modified SRB for the ride up defeated that purpose and gave a particular irony to the whole notion.
The descent stage of Altair would not have had to be so oversized due to not having LOI requirement. Alternately, had they still wanted to do LOI with Altair, it would have had drop tanks rather than taking the big tanks all the way to the surface.
3) Build a completely new scalable Kerolox-core 25-100t IMLEO launcher similar to the Atlas-V Phase-2/3A - The most costly as you'll be developing just about new everything. However, it would actually be a better option if you are wedded to the "1.5-Launch" concept as you won't need a different core for your CaLV heavy lifter, just a cluster of your CLV cores and maybe a wide-body upper stage.
No ATK.Giant 5-segs and keeping ATK in the money was the biggest problem.Unfortunately... well
The best CxP, IMHO, would have been switching to all commercial launches with NASA pushing technology forward (similar to NACA, back in the day) done in parallel with NASA developing a first generation LOX/LH2 orbital fuel depot. I'd also have kept Orion, Altair, and EDS (launched on a commercial launcher). Having NASA focus more on the actual beyond LEO part of CxP should have been emphasized instead of the "1.5 launch" architecture, which only gets you to LEO when you assume the EDS is classified as part of the "beyond LEO" part of the program.
@ Archibald. I suppose that it is possible to be wise in retrospect when looking back at these things. IIRC, the ESAS study was done in about 2008. Would the EELVs have been seen as super-reliable and a no-brainer then, especially in relation to the shuttle stack?
In an ideal world the expensive and extensive shuttle infrastructure should have been scrapped in favour of phase 1 EELVs. Phase 1 EELVs should have been cheap for two reasons - a) they derived from existing and reliable rockets and b) they added their numbers to ordinary EELVs mission as flown by the military and NASA scientists. Unfortunately even in that scenario, the EELVs have become so damn expensive those years that I'm not sure that scenario would have been viable. Why the hell are EELVs become so expensive ? they are good rockets which work quite well. They have a reasonnable numbers of missions and customers. So what ?Next best option after EELVs would have been the small DIRECT Jupiter 120 and/or 130 later involving into AJAX. An interesting question would be, could AJAX or Jupiter 120/130 end cheaper than phase 1 EELVs ?
What are other people’s thoughts?
And, with L2 rendezvous, the lander and CEV would be of near-equal mass. That neatly allows a two-launch profile with two nearly-identical vehicles. The launch vehicle itself would have been significantly smaller than Ares V/SLS, and closer to Direct's Jupiter-120 or three-core Atlas Phase II.
Quote from: jeff.findley on 01/07/2013 06:35 pmThe best CxP, IMHO, would have been switching to all commercial launches with NASA pushing technology forward (similar to NACA, back in the day) done in parallel with NASA developing a first generation LOX/LH2 orbital fuel depot. I'd also have kept Orion, Altair, and EDS (launched on a commercial launcher). Having NASA focus more on the actual beyond LEO part of CxP should have been emphasized instead of the "1.5 launch" architecture, which only gets you to LEO when you assume the EDS is classified as part of the "beyond LEO" part of the program.I agree with this. Wasn't this how it was pre-ESAS?
I think a better CxP would have looked like of the ELA and LANTR concepts of the 90s.One thing they really got wrong was giving the shuttle a set in stone retirement date.Instead they should have worked on getting OSP finished as quickly as possible on an existing rocket.While this is taking place slowly transition the shuttle to shuttle-C.
In the interests of absolute crew safety, my pet idea was a modified DIVH with an RS25 on the core, RS68A on each booster, and no upper stage. I reckon that would make for an impressively reliable vehicle.
The shuttle shouldn't have been cancelled.It was a scam.The money goes to SLS which does nothing because of various reasons that are outlined in many of my other posts.
Cancel the Shuttle program immediately after Columbia.Eat the Gap immediately. Soyuz and Progress to incomplete ISS in the interim. It worked well enough for MIR.Develop two competing crew capsules for EELV launch.Develop something like the ULA Payload Bay concept for the remaining ISS modules. I think this assembly method was workable with Soyuz, so some assembly could be accomplished prior to the crew vehicles coming online.Some type of domestic cargo ship program.For the moon, some type of storable propellant medium lift based architecture.
Quote from: spectre9 on 02/17/2013 12:49 amThe shuttle shouldn't have been cancelled.It was a scam.The money goes to SLS which does nothing because of various reasons that are outlined in many of my other posts.The shuttle, as it existed, -should- have been cancelled. It was inherrently overly costly and complicated and dangerous. It was very cool, but not particuarly practical. At least at the flight rate and cost that it ended up having.By the time of the Columbia accident, that was abundantly clear. It just took that to break the beurocratic inertia of an established program. I don't agree it should have been cancelled right away, but that it was replaced was a good thing.Now, if the Shuttle was was launched on top of an INT-21 stack, and perhaps had a break away cabin with an LAS system, then that'd be another story. That would have solved the safety issues. Etc. etc. But I don't know that would have solved all of it's high expense and plethera of man-hours t process between flights.SLS was a political decision, but it doesn't change the problems inherrent to the Shuttle.
LOC numbers were fine and getting better all the time.
Sitting on the ground is safer than anything.
SLS will be more likely to face LOM on early flights because it will not be tested many times.
Overly costly? What by allowing usage of Al-Li ETs and reuse of SSME? I'm not so sure about that in hindsight. I think that was talked up a bit.
It can't be a good thing that it was replaced because that never happened. That might happen some day but don't count your chickens before they hatch. Everybody is riding on Soyuz which costs big dollars.
Rubbishing the shuttle because of a lack of LAS is a poor argument and I don't buy it. If I did at some point I was wrong.Shuttle would've kept 4-seg solids around at least. ATK couldn't complain too much.
Two problems with that:1. Thanks to the Shuttle lobby, no competitive human launch system would be developed simultaneously with Shuttle. (Just look at the history of cancelled projects) That's why Shuttle had to go away to allow replacements (be it Orion or CCrew)2. Shuttle-C only made sense if run together with Shuttle, to allow sharing of infrastructure/costs. With shuttle gone, Shuttle-C no longer makes any sense.
Cancel the Shuttle program immediately after Columbia.
Phase 3:Turn over space launches and lunar base supply delivery to private sector (COTS), NASA responsible for operation of in-space exploration equipment and lunar surface research installation.
Quote from: Lars_J on 02/16/2013 10:15 pmTwo problems with that:1. Thanks to the Shuttle lobby, no competitive human launch system would be developed simultaneously with Shuttle. (Just look at the history of cancelled projects) That's why Shuttle had to go away to allow replacements (be it Orion or CCrew)2. Shuttle-C only made sense if run together with Shuttle, to allow sharing of infrastructure/costs. With shuttle gone, Shuttle-C no longer makes any sense.That why I would have slowly transitioned the shuttle to an unmanned system with it eventually becoming Shuttle-C and then the Jupiter 130.ATK gets their money and KSC workers stay employed etc.Some of the orbiter contractors will loose out but they could bid on the next vehicles.Same goes for workers in the orbiter processing facility but many of them could end up being reassigned to other tasks.Quote from: Kaputnik on 02/16/2013 08:20 amIn the interests of absolute crew safety, my pet idea was a modified DIVH with an RS25 on the core, RS68A on each booster, and no upper stage. I reckon that would make for an impressively reliable vehicle.I had the same idea but kept the DCSS.Quote from: libs0n on 02/16/2013 11:43 pmCancel the Shuttle program immediately after Columbia.I would have rushed the X38 as some sort of assured access vehicle in that case.Finish the prototype and build two more then stick one on an Atlas V for an all up uncrewed test.Use the aerodynamic prototypes for LAS testing.You'll also need to build a space tug for the EELVs so they can finish assembly ISS.Something like the SS/L 1300 based tug might work.
Quote from: DLR on 02/21/2013 04:18 amPhase 3:Turn over space launches and lunar base supply delivery to private sector (COTS), NASA responsible for operation of in-space exploration equipment and lunar surface research installation.Only problem is that the private sector already handles all launches except the shuttle therefore it just duplicates in NASA what is being done already. In short if you are using Atlas or Delta there would be no need for COTS for the launcher and maybe a cots program for the spacecraft.
Well that was a big and inefficient post but I'll respond. I really think you need to be more coherent and keeps things concise. It's really an issue for me with your posting style and it leads me to glazing over many of your responses around the boards.Space it out more, say more with less. Improve your signal to noise ratio.
Most of your argument seems to center around overhead.Well SLS DDT&E costs rival those costs and it gets 0mt of useful payload to orbit every year until it does a test flight in 2017 and then again in 2021.What it really amounts to is jobs @ KSC vs jobs @ MSFC.If LAS is a big problem for some then they're welcome to refuse to ride. It's their choice.Perhaps Apollo CSM shouldn't have been cancelled. The U.S. seems to have a history now of cancelling good working spacecraft. This is the problem I have.Development costs are huge for new hardware. There's no way around that.Sidemount wasn't that big an issue. Big money has been spent of things like OBSS and on orbit tile fixing methods. STS-1 landed without some of the tiles. Columbia had a big down mass putting stress on it.Commercial crew/cargo seems to be taking an eternity to come online and by that time ISS is going to be old and needing serious repairs costing big money to keep it in orbit.Yes shuttle would've needed OMM to keep going but that's a good thing. Upgrades were made on them all the time making them better. A new orbiter could have been built too. That would be so much cooler than a SLS.I think we can agree on one thing. It would've been nice to keep shuttle going while commercial crew is in development. A smooth handover without the large cost of manned spaceflight on the Soyuz would be a good thing.Yes the shuttle had problems but most of them had been ironed out in sunk cost. Going through all that again with SLS is going to be tiresome even if it is a more robust system to begin with. It's not exactly built from the ground up as a RAC2 like vehicle would be.Instead of doing SLS money could've been put into the F-1 engine so that when the time is right MSFC could start working on the better design for SLS. I still believe this will happen anyway. Shuttle derived design work might have wasted lots of time/money but that doesn't bother me at all.
Well, I won’t deny I can be verbose in my post. But we all can’t be professional writers like you are apparently. If my posts bother you so much, please feel free to not respond to them. I promise I won’t loose any sleep over it. Is that concise enough for you?
This seems like a big and inefficient post to me, but I’ll respond anyway…;-)Most of your argument seems to center around DDT&E costs. But those could have been just a fraction of what they are turning out to be with a different approach than Ares 1/5 and later SLS. An Orion with a LEO service module could be flying to the ISS on an Atlas-552 as soon as the CSM was ready. But those are acceptable DDT&E costs for the Orion CSM itself, because we need something new or we’ll never leave LEO flying on the Shuttle ever again…LAS concerns aside. Atlas-552 would only need a man-rating development costs. Both of those are reasonable without the overhead of the entire shuttle stack and hardware.The HLV to go with Orion flying on an Atlas 552 would be a significant DDT&E cost. But again, unless you want to stay in LEO forever, we need a new LV. Although, there were far better ways to go about this than Ares V and SLS without breaking the bank on DDT&E costs. A pair of upgraded Delta IV heavy’s could get over 100mt to LEO, or a 7-core Delta Super Heavy could get almost 100mt to LEO. Couple that with Orion on Atlas-552 with 5m upper stage (which could launch full BLEO Orion), and you have a 2-launch lunar architecture with Apollo-scale capability. And synergy with EELV’s is maintained. Delta IV doesn’t need to be man-rated, as it would just be a cargo launcher. IF you want CxP scale, then add an upgraded D4H launch of the lander for EOR with the EDS on D4SH, and Orion on Atlas-552/w 5m US, and there you go. Minimal DDT&E from what was already flying…just the addition of a larger upper stage, and some other upgrades to the EELV’s. Overhead is just a fraction of the Shuttle stack (or Ares 1/5 or SLS), because ULA already has all of the capabilities running anyway for USAF/DoD. Conversely, Direct 3.0 could have been chosen, with Atlas-552 still used for ISS servicing by Orion, and Orion riding on J-130 and J-246 on lunar missions. This would have probably not cost much more DDT&E than D4SH, but the overhead costs of it would probably be more than all EELV-derived because nothing else will use the 8.4 core, SRB, RS-25, or JUS. Still, it would have used all the kept most all of the Shuttle infrastructure and personnel in place while using the Shuttle’s proven hardware, and taken us to BLEO again.Either way likely would have only cost a fraction of the DDT&E costs that it turned out, and not required a commercial cargo or crew program to be funded (for better or worse, depending on your point of view…) as Orion (as Orion was originally envisioned in ESAS) would have taken care of both of those roles.
I thought about attaching this to a previous hypothetical thread of mine:http://forum.nasaspaceflight.com/index.php?topic=30229.0But, after reading a little more of the ESAS report when I had some time to kill, I ran across some things I hadn’t read before (over 700 pages, so that’s not too odd).Now, the original version of CxP doesn’t seem -too- bad in theory really. Air-started SSME, use of STS 4-seg for Ares 1 to get Oriong flying quickly.
The obvious answer for some on this will be “Direct”, and they seem to evaluate Direct-like LV’s. LV 24 and 25. A J-130 anyway. But they seemed fixated on launching the crew on the stick, so the turned the ET-sized core with 4-seg boosters and 3XSSME into one Ares 1 launch plus two J-130 launches if I understand them correctly. They really don’t seem to evaluate LV24/25 as a two-launch system with no Stick. Am I missing something? Or is that correct?
1) What would have been the best CxP given what ESAS evaluated?
2) What was the best system not evaluated by ESAS for CxP?
I’m bumping this with a bit of an addition parameter.First, does anyone know in particular why McDonnel Douglas went with a hydrolox booster on Delta IV for the EELV competition? Especially when it needed a new engine developed? (I’m assuming Jim probably knows, :-) )I mean, hydrolox isn’t the best 1st stage booster. It required a much larger booster core than Atlas V or any similar performing kerolox booster. Delta II used the kerolox RS-27 engine. There wasn’t a US made kerolox engine other than RS-27 that I know of, but there wasn’t a US made hydrolox booster engine either. RS-25 is a sustainer engine, not really a booster engine.So, if MD was going to evolved Delta II for EELV, why didn’t they stick with the RS-27, and grow the core to 5m, and put maybe five of them on there? Or maybe four with GEM-60 SRB to get it off the pad? Four of them had more thrust than the first RS-68, and not much less than RD-180. What was the thought process to switch to a brand new engine development, and a propellant that isn’t the best booster propellant, not to mention being one of the most temperamental propellants. I see why the Russians and SpaceX use kerolox for the upper stage for commonality and because it’s a really easy propellant to handle and I think rockets that use kerolox are cheaper overall than hydrolox. LH2 is the most difficult and so they wanted to make the whole rocket use it?Hopefully someone can enlighten me on that. Especially when the Delta II already used a 200klbs kerolox engine that probably could have been upgraded to get to around 250klbs without much trouble.Ok, so I set this up for a bit of alternative history going back to the EELV program for this thread.So, MD wants to create new 5m wide rocket core tooling, and a new engine, and a new upper stage using RL-10 engine for Delta IV?What if instead, they went with a 5m wide kerolox booster, which either used 4-5 RS-27A’s (or upgraded versions with more thrust), or, instead of having PWR create the RS-68 new, have them dust off the F-1, and create maybe an “F-1S” version of the F-1A. I guess the F-1B is going to be like this, but like the J2S, make the F-1S with a specific eye for being simple and cheap. A big Merlin 1D in effect maybe? Maybe a larger upper stage (because the GG F-1 won’t be as efficient as a stage combustion kerolox engine like the RD-180) and maybe RL-60’s on it. They were 90% developed by 2003 anyway.So, you have something similar to an Atlas V-phase 2, but with probably less first stage burn and more 2nd stage burn. This LV should probably put somewhere between 20-25mt to LEO, which would fulfill the upper end of the EELV requirements I believe. No need for a tri-core heavy version. And while it would seem overpowered for the bulk of the EELV payloads that Atlas V and Delta IV Medium handle, would it be any more money than Delta IV? It might be more money than Atlas V, because the US-made F-1B would be more expensive each than the RD-180’s. But You have an LV that would be be shorter than a Delta IV medium, cost about the same, but put up D4H payloads. GEM-60’s should bump that up easily if ever needed. I mean, it’d basically be the same hardware as a Delta IV medium.So, let’s say MD developed that, and let’s say Boeing buys them. And even if Boeing is caught stealing info from LM and ULA is formed, This version of Delta IV would exist.So, during the ESAS evaluation, where NASA evaluated Atlas Phase 2, as well as an 8m wide Atlas X, they could evaluate this LV. The single stick version should get Orion to LEO. But it could be stretched, and have another F-1 added, and you basically have the Dynetics booster. Now you have a crew launcher with direct synergy with EELV, and a cargo launcher with much synergy with EELV, except NASA could launch it from their pads at KSC (as Boeing would have had no reason to build the ability to launch a tri-core heavy from LC-37, since the single-stick would handle up to Delta IV-heavy roughly).So the tri-core heavy would be only used by NASA. And they could build the larger upper stage/EDS for it. It only has two boosters, which was another requirement they seemed to fixate on in ESAS. This cargo launcher would have six F-1 engines, and with a larger EDS, it should throw easily what Ares V was supposed to, to LEO. NASA could have PWR develop the J2S (not the J2X) as was originally envisioned in ESAS on the cargo launchers. It was mostly developed already, and should have been a relatively cheap and easy development, rather than the J2X which I understand was a very different engine than J2S. And I don’t know if they could fit enough RL-60’s on it. But it should be able to fit a couple of J2S under there. So, putting aside for a moment the politics of the time probably made SDHLV inevitable, this EELV derivative seems like it would have met all of what seemed to be NASA’s ESAS criteria. No more than two boosters, 25mt crew launcher, 125mt cargo launcher, 1.5 architecture, etc. And with a famous US-built engine. NASA evaluated Atlas Phase 2 heavy, but seemed to reject it as you’d need two of them for their planned architecture, and they wanted 1.5 architecture. Atlas Phase 3A would have probably worked, but it had more than two boosters, and they said it wouldn’t even fit on any existing pad, which I think was because the four boosters were placed at 90 degrees to each other, making it just over 15m in depth as well as width, which I think is a problem to fit it on a ML with tower.Could this have been the better CxP? While having a lot of synergy with EELV’s? The only new developments over a Delta IV with single F-1 engine, would have been the stretched 5m core, making the tri-core heavy, man-rating it, and a new wide upper stage with J2S engines)Compare that with CxP in developing a new 8.4m core (using existing tooling) a new Ares V upper stage, a new Ares 1 upper stage, J2S for Ares V anyway, air-startable SSME for Ares 1, and 5-seg booster.
Quote from: Lobo on 01/04/2013 11:31 pmI thought about attaching this to a previous hypothetical thread of mine:http://forum.nasaspaceflight.com/index.php?topic=30229.0But, after reading a little more of the ESAS report when I had some time to kill, I ran across some things I hadn’t read before (over 700 pages, so that’s not too odd).Now, the original version of CxP doesn’t seem -too- bad in theory really. Air-started SSME, use of STS 4-seg for Ares 1 to get Oriong flying quickly.Ares I was never needed. DIVH can do it even today, sans man-rating straw man, and dealing with that straw man is at most a few billion $.
First, does anyone know in particular why McDonnell Douglas went with a hydrolox booster on Delta IV for the EELV competition? Especially when it needed a new engine developed?
Quote from: gospacex on 05/08/2013 12:28 amAres I was never needed. DIVH can do it even today, sans man-rating straw man, and dealing with that straw man is at most a few billion $.Delta IV HR for LEO Orion and DIVH for Lunar Orion unmanned test flight. For crew Orion ( LEO or BLEO ) the J-130 was needed.
Ares I was never needed. DIVH can do it even today, sans man-rating straw man, and dealing with that straw man is at most a few billion $.
No, DIVH is sufficient for crew Orion to LEO.
My impression was that it had to do with development cost and the results of earlier Advanced Launch System studies. Rocketdyne had done a lot of early work on the STME (Space Transportation Main Engine) for ALS. McDonnell Douglas decided to leverage that already completed work so that it could spend less money on engine development. RS-27A clusters were non-starters due to cost and performance.Boeing proposed an SSME powered core. Lockheed Martin (Marietta) was going to go with RD-180 or NK-33. (McDonnell Douglas probably figured that Russian engines would be a non-starter for the USAF.) Alliant was proposing big composite solid lower stages. EELV was a winner take all competition to decide which company would control access to space for the foreseeable future.The Air Force had seriously considered ALS and STME, so McDonnell Douglas probably thought LH2 was simply the way to go. Rocketdyne served up RS-68, which was a cheaper, though lower ISP design than STME. It all probably looked cheap compared to Titan IV and Space Shuttle back then. Times were different.Delta IV was developed and has been successful. It is the only 25 tonne to LEO class launch vehicle in the inventory, and currently stands as the world's most capable launch vehicle. - Ed Kyle
{snip]And if there had been a 5m F-1 powered kerolox version of Delta IV instead of hydrolox, could that have been a building block LV that NASA might have more readily wanted to use during the ESAS study?A better CxP?
Looking at the easier Delta 4M comparison, if the existing 4-meter second stage were used an RS-27A powered first stage would have to gross 500 tonnes (40% more than Atlas V CCB) and be powered by eight engines to match Delta 4M performance to GTO, which is the key mission.An alternative would be to add one or more RL10s to the upper stage, allowing it to carry more propellant, but that would add cost and reduce upper stage specific impulse. A Delta 4 Heavy type upper stage, but with two RL10 engines, might shrink the first stage down to 400 tonnes and six RS-27A engines.RS-27A wasn't actually designed to be a booster engine. It has a bigger nozzle than the previous H-1/RS-27 to get better vacuum ISP, but that came at the expense of liftoff thrust. RS-27A doesn't throttle either, which would be a problem for an EELV.
By the way, during the 1980s General Dynamics entered the CELV competition (won by Martin Marietta's Titan 4) with a rocket that might also have fit the bill for EELV. It proposed a 200 inch diameter first stage powered by five "H-1D" engines, augmented by four 67 inch diameter solid rocket motors. A Centaur G-Prime with two RL10 engines would have served as the upper stage. This thing would have put 5 tonnes into GEO (probably 10 tonnes in GTO), but the solids were new (roughly equal to Japan's beefy SRB-A motors) and the first stage was new and all-new pads would have been needed, so it lost. Still, the concept shows what was possible. - Ed Kyle
Why write a whole page for something that can be simplified into 3 lines?Orion CM/SM Mass to LEO - 22 tonsDelta IV Heavy lift capacity to LEO - 22 tonsAres I lift capacity to LEO - 25 tonsNo margin on DIV for Orion
I am starting to believe that there never has been any justification for Orion under any scenario. It's designed for a Mars direct return trajectory. Dragon or a beefed up CST-100 could handle lunar return. I think hauling an Orion to Mars and back is too much mass. Have a DS hab at EL1/2. Ride to rendezvous in Dragon or CST-100. Transfer. Go to Mars and return to EM L1/2 in hab, transfer to a Dragon or Boeing capsule for reentry. Leave the hab parked for next mission. Or use an Aldrin cycler and rendezvous as it swings by. Orion only has a 21 day active use capacity, so its use as a lifeboat is very limited. I'd rather expend Delta V on decelerating the hab for reuse than sending Orion's great mass all the way to Mars and back when it really isn't necessary. A better CxP would not have included such a massive capsule. It would have used a less massive capsule that would go to LLO or EM L-1/2 and back, but not to Mars.A lighter capsule would have prevented Ares I performance from ever becoming an issue.
Interesting concept. As the SM's not designed yet, maybe the design could be changed to that? I don't think there's much to be done with the CM at this point.
Quote from: Lobo on 05/21/2013 12:33 amInteresting concept. As the SM's not designed yet, maybe the design could be changed to that? I don't think there's much to be done with the CM at this point.It's not?
They danced around this a lot, and had no problem looking at a new diameter core in their concepts. KSC can't handle an 8 or 8.4m tri-core LV, but the 5-5.4m wide hydrolox LV is a little to small. And they didn't seem to like the 5-5.4m wide kerolox Atlas Phase 2 because it needed 2-launches of tri-core LV, or a 5-core AVP3a and NASA didn't like that many boosters and the depth dimension.But no one thought to look at maybe a 6-6.5m kerolox core with 3-4 RD-180's?It's over powered but workable for a crew launcher, and a tri-core version is as capabile as the LV 27.3 they chose.One new core, and one new upper stage (it would need J2S but so did LV27.3), and NASA has both a new crew launcher, and cargo launcher. And the crew launcher could probably use Delta's existing DCSS like I said, for a little more synergy with EELV.The cores could be produced at a reasonable clip at MAF, along with the new HLV upper stage (when needed, down the road). Seems like such an obvious option, what am I not seeing? Why wasn't it even looked at, even if they opted for Ares 1/5 anyway.
{snip}Saving a billion a year on the launcher, but losing 5 billion a year in NASA's overall budget, would be a very bad trade indeed as the losses would mostly be directed towards the Science directorate.Though I personally am not a fan of the current direction for SLS, it still represents the backbone of NASA's entire political support structure and without that, NASA could be in a much, much worse position.Ross.
A_M, Unfortunately it doesn't work that way.There is at least a decade's difference between when NASA's political support mechanism was destroyed, and when there could potentially be a moon base -- it just takes that long to develop all of the systems required.{snip}
SLS and Orion are development projects not a manufacturing operation.The Moon base would be a development project.The overlap is smaller, particularly since NASA can start development in s few months.
The thing most people here (me included) have a really hard time swallowing is that the politics is sadly 90% of the fight. Without it, the other 10% doesn't matter at all. Loathe this truth to your heart's content. But ignore it at your peril.