Talk:Space Launch System/Archive 1

2011 Merge proposal
I object merging. The SLS is a different proposal (one of the many Shuttle-Derived Launch Vehicle proposals) - not related to the specific side-mount Shuttle-Derived Heavy Lift Launch Vehicle proposal. Alinor (talk) 06:51, 26 April 2011 (UTC)


 * Yea, the IP user that tagged the articles did not provide any justification for merging them. Looked like drive by tagging to me.. -Fnlayson (talk) 14:33, 26 April 2011 (UTC)


 * Agree - no. If no one has any objections, I'm removing the tags.  SchuminWeb (Talk) 05:39, 28 April 2011 (UTC)
 * In this case I suggest removing the merge templates. Alinor (talk) 07:45, 2 May 2011 (UTC)


 * A Late Objection- A Shuttle-Derived heavy launch vehicle is a Space Launch System. NASA is seeking an alternative Space Launch System to the Ares family; possibly a system like the Jupiter (rocket family) in the DIRECT Shuttle-Derived Launch Vehicle architecture. I don't know the difference between the Jupiter and the Ares V family of Shuttle-Derived Launch Vehicles but I'm sure they are all Space Launch Systems. SEC. 302."SPACE LAUNCH SYSTEM AS FOLLOW-ON LAUNCH VEHICLE TO THE SPACE SHUTTLE." of S.3729 NASA Authorization Act of 2010 doesn’t name a new system it gives NASA the authority to develop a system that can "access lunar space and the regions of space beyond low-Earth..." without saying that system must be the Ares or any other specific launch system. Smgntion (talk) 02:45, 10 July 2011 (UTC)


 * regardless of how set in stone a new design is, there is no doubt that there is something being developed that's not directly a copy of any of the previous SDLVs and most news articles refer to it as SLS. The SDLV article discusses the many proposals while this focuses on the vehicle being built by NASA TMV943 (talk) 11:48, 10 July 2011 (UTC)

Ares IV
So, I've been doing a casual search on the NASA site and associated agencies, but haven't found much more information on the SLS. However, it sounds very much like the Ares IV concept. Has anyone seen any NASA artwork or good descriptions on how SLS will be configured? TANSTAAFL (talk) 16:27, 19 May 2011 (UTC)


 * NASA has not decided on a configuration yet. The agency is still studying various Shuttle-derived vehicle configurations.  It may be something like a smaller Ares IV or Ares V Lite to follow the NASA authorization act.  Look over the article in reference 3 on the main SLS page and maybe others articles on spaceflightnow.com. -Fnlayson (talk) 20:21, 19 May 2011 (UTC)


 * Well NASA has a general SLS configuration and has put out status reports for Congress in January 2011 and Feb. 2011. I also found some later press releases and documents without SLS details using this google search.  The Feb. one shows a general SLS config, btw. -Fnlayson (talk) 12:49, 27 May 2011 (UTC)

Article could use a diagram
Has NASA produced any diagram or other graphic of this vehicle. Article would be improved with a graphic. N2e (talk) 12:18, 23 May 2011 (UTC)


 * No design finalized yet ( as per my question above)... it will probably look similar to other shuttle derived launch systems, but alas no exact or even near-guess images yet... TANSTAAFL (talk) 18:13, 24 May 2011 (UTC)


 * This NASA Feb. 2011 report has a general configuration layout diagram that could be used. -Fnlayson (talk) 12:53, 27 May 2011 (UTC)


 * Done, see File:NASA SLS ref config Feb 2011.png from page 4 in the linked report above. -Fnlayson (talk) 16:41, 6 June 2011 (UTC)

On the news, DIRECT
Just read at http://www.bbc.co.uk/news/science-environment-14915725 that NASA officially unveiled the SLS. There is an image there that you could use. Wingtipvortex (talk) 15:54, 14 September 2011 (UTC)

The design of the SLS seems to be a direct copy of the DIRECT 3.0 design. Can anyone confirm? If so, can we put a reference?13:11, 15 September 2011 (UTC)


 * Maybe very similar, but not likely an exact or direct copy. These all fall under Shuttle-Derived Launch Vehicle, so they will look a lot alike... -Fnlayson (talk) 16:29, 15 September 2011 (UTC)
 * Agreed. DIRECT 3.0 became basically the old National Launch System in the low-Earth-orbit form (with one fewer engine), and added a full 8.4 m modern lightweight-design second stage (and an extra SSME) for beyond-Earth-orbit missions. NASA's current Block 1 design is somewhat like the NLS. Block 1a is very close to some DIRECT beyond-Earth-orbit designs, but uses one extra engine. But, I think Fnlayson is correct in stating that the unifying concept is that they are all shuttle-derived designs. If specific missions arise where multiple launches of similar rockets are used, that would surely represent an emphasis of specific DIRECT ideals. Fotoguzzi (talk) 21:00, 6 October 2011 (UTC)
 * I am not just referring to the physical appearance but the key attributes of the design. Namely, the plan to reuse the RS-25 and 5 segment solid fuel boosters as well as the inline fuel tanks. This differs significantly from the Ares design and is one of the main features of DIRECT v3 and the SDVs. 12:16, 16 September 2011 (UTC)
 * I was referring to the vehicle's configuration, not simply external appearance. I don't think further discussion is worthwhile until a reference that goes it to this is found.. -Fnlayson (talk) 14:59, 16 September 2011 (UTC)

Saturn INT-nn
Suggest performance, visual (and fuels) closer to Saturn INT-18 http://en.wikipedia.org/wiki/Saturn_II_%28rocket%29#Saturn_INT-18 rather than the INT-20?Paulbeeb (talk) 06:48, 16 September 2011 (UTC)
 * SLS resembles Saturn V in that it is pointy and large. That is about it. These sentences really should be removed or drastically rewritten. It might be fair to note that the paint schemes in the illustrations are meant to be redolent of the Saturn V, but the actual SLS rockets would have the standard orange foam insulation on the cryogenic tanks. Fotoguzzi (talk) 21:05, 6 October 2011 (UTC)

Schedule
I'm torn between keeping and removing this section. The keep side of me says that the first question people coming to the article will have is "when?". The remove part of me says that this is speculative information at best (though it's reasonably referenced) and represents a "worst-case" scenario and could be very misleading as a result. Thoughts?--RadioFan (talk) 14:18, 16 September 2011 (UTC)
 * Converting the table to a bulleted list or a paragraph with less detail would help, I think. -Fnlayson (talk) 15:33, 16 September 2011 (UTC)

SLS launch cost per pound or kg to LEO
we should make the comparaison table of the 5 scenario until 2025 to see what kind of numbers it will give --Beaucouplusneutre (talk) 07:10, 20 September 2011 (UTC)
 * i find something between 60 000 and 30 000 per kg to leo from the cheapest to the most expensive options, even with 12 flight, its 3 times more than a commercial rocket.--Beaucouplusneutre (talk) 12:45, 21 October 2011 (UTC)

Shuttle side-mount
does my use of it was sounding innapropriate ? of course it was not built.Spudis original proposal is in between commercial and sls.I will correct the sentence to make it less ambiguous and provide a link to the study.To improve this section maybee we should separate it into 4 paragraph ( political reaction, space advocacy, technical/commercial issues, alternatives, with pro and cons in each sections, maybee into a table format ? --Beaucouplusneutre (talk) 15:35, 4 January 2012 (UTC)


 * The sentence is talking about current launchers and derivatives of existing ones. Side-Mount was just a concept.  Side-Mount is no more relevant than the several Shuttle-based designs NASA has studied over the years.  I don't see the point in singling this one out here.  That's why Shuttle-Derived Launch Vehicle is linked. -Fnlayson (talk) 15:55, 4 January 2012 (UTC)


 * I am ok with that.I will find a way to compact the pork barrel cited 3 times into 1 sentence, also citing newt gingrich could be nice (he the only candidate with a space interst), --Beaucouplusneutre (talk) 17:09, 4 January 2012 (UTC)

Please remove Ref 31 from this sentence -- it implies that I advocated EELV and or commercial launch vehicles in my blog post. I did not; I was demonstrating that a feasible heavy lift vehicle was possible with Shuttle side-mount at less cost and sooner than SLS. Spudis (talk) 13:24, 3 February 2012 (UTC)

Propellant depots
any idea where the propellant depot word got lost and the nasa studies of depots vs sls (http://www.spaceref.com/news/viewnews.html? ---and ---http://satellite.tmcnet.com/topics/satellite/articles/230642-did-nasa-hide-in-space-fuel-depots-get.htm) ? --Beaucouplusneutre (talk) 17:09, 4 January 2012 (UTC)


 * I think the wording may have been changed to 'on-orbit refueling' or something like that. I added 'depot' back in there to match common terminology for it. -Fnlayson (talk) 18:24, 1 March 2012 (UTC)


 * thank you, a wikilink to Propellant depot could help too--Beaucouplusneutre (talk) 11:57, 3 March 2012 (UTC)

Upper stages
It seems the upper stages are exactly other way around;

The "cps" with RL-10 is the earth departure stage, used for missions that go further than LEO; In this configuration the core of the booster(stage1) goes all the way up to orbit(like when operating without second stage), and the cps is used just as earth departure stage.

The later upper stage with J-2X is for heavier loads to LEO. In this configuration the rocket is heavier, and the core/first stage cannot lift it to orbit, L2 stage lifts it into orbit. — Preceding unsigned comment added by Hkultala (talk • contribs) 21:42, 5 February 2012 (UTC)

Opposition
The Criticisms/Opposition should include points, quotes from leading space flight sites/authors/groups. This page should not be just a one-sided, party-line NASA cheer-leading/propaganda instrument. — Preceding unsigned comment added by Wrwhiteal (talk • contribs) 17:52, 20 October 2011 (UTC)


 * You and others have already done that, but without any balance. Too much detail and quotes also. -Fnlayson (talk) 17:55, 20 October 2011 (UTC)
 * Where exactly in the article is this NASA cheerleading stuff anyway? The text presents the plans and events without biased wording. -Fnlayson (talk) 18:02, 20 October 2011 (UTC)
 * The critiscism /opposition section should be huge given the amout of controversy this programm provoke.--Beaucouplusneutre (talk) 12:17, 21 October 2011 (UTC)
 * More 3rd party sources need to be used instead the self-published ones from the group/organization to better follow Wiki policies (WP:V, WP:RS). -Fnlayson (talk) 15:12, 21 October 2011 (UTC)
 * Can you define what '3rd party sources' are acceptable to you, if ott Space Interest groups like 'the planetary society', 'Space Review', 'Space Access Society', 'Tea party in space', 'Space Frontier society', 'mars society', etc... Why not put the opposing opinions/reporting by established space advocate groups out and let readers decide? — Preceding unsigned comment added by Wrwhiteal (talk • contribs) 16:02, October 21, 2011 (UTC)
 * the quotation and citing some website (space review, competitive space) break the lisibility (interested readers use the refs).--Beaucouplusneutre (talk) 00:14, 16 November 2011 (UTC)
 * Please sign your posts. Look over the links provided above.  I have generally only removed or summarized what seems to be redundant text/info and removed a couple SPS refs in an effort to prevent giving undue weight to one side. -Fnlayson (talk) 16:06, 21 October 2011 (UTC)
 * I just want to add that I support the presence of an opposition section in this article. I find it much easier to navigate by having it. My first natural thought reading this article was "I wonder if this was the best plan for NASA" and being able to jump to an opposition section was the quickest way to find information about the various arguments.JettaMann (talk) 16:43, 14 November 2011 (UTC)
 * Opposition should be retitled Criticism and be limited to a summary of bullet points while the rest of the section should become a separately linked "Criticism of the SLS Program" article. Doyna Yar (talk) 20:16, 17 November 2011 (UTC)


 * It is really all the same. Whatever you want to call it.  If you mean separating criticism of the rocket from criticism of program, that can be difficult to do. -Fnlayson (talk) 21:09, 17 November 2011 (UTC)


 * Things that should stay in the critiscism section, a link to propellant depots, proper funding of ccdev, asteroid manned mission projected at $ 143 Billions.things that could be moved : quotes of Tumlinson and Rohrabacher, 3 citation of pork barelling (one is enough and maybee congressional earnmarks is more appropriate), citation of The Space Review, SpacePolitics.com, Competitive Space Task Force.Your Thoughts ?--Beaucouplusneutre (talk) 07:33, 29 January 2012 (UTC)


 * Modifications have been made, comments ? --Beaucouplusneutre (talk) 22:16, 7 March 2012 (UTC)
 * This seems to be a closed issue, so I'll remove the tag. Viriditas (talk) 13:26, 9 April 2012 (UTC)


 * I find that of the critics currently referenced, the majority exist as competitors for funding - directly or indirectly through NASA initiatives/support for private space enterprise. cmasiero (talk) 21:09, 22 Febuary 2012 (UTC) — Preceding unsigned comment added by 220.244.251.49 (talk)

Why did "Criticism" get changed to "Alternatives"? The entries in that section really are criticisms, and should be headed as such. If we want another section entitled Alternatives, we should add one. I'm going to go ahead and change it back, since the current section title doesn't match what's in the section. Even if you're a big fan of SLS, it doesn't hurt to have a section for criticisms in the Wikipedia entry.

There should also be a paragraph to the effect that SLS can only loosely be called "Shuttle-derived", given that it shares no parts in common with the Space Shuttle. Even the SRBs are a completely different design. It could more accurately be termed "Constellation-derived". Voronwae (talk) 04:17, 11 June 2012 (UTC)


 * It uses the same SSME engines and the SRBs are only lengthened by a segment. These are Not completely different. Plus it use the Shuttle stack configuration like other Shuttle-based vehicles at Shuttle-Derived Launch Vehicle. No reason to pick nits on this. -Fnlayson (talk) 14:33, 11 June 2012 (UTC)
 * concur including the tanking. Perhaps it's better thought of as an 'Evolved Shuttle-Derived Launch Vehicle' with a bit of unofficial DIRECT influence. Doyna Yar (talk) 03:51, 12 June 2012 (UTC)
 * Yes, right. Something stating the degree of Shuttle connections would be good.  Provided sources for such details can be found. -Fnlayson (talk) 04:09, 12 June 2012 (UTC)
 * When the time comes for it an 'Engineering Lineage' section is a great idea. Doyna Yar (talk) 04:25, 12 June 2012 (UTC)

Support section
to balance the opposition one, i think its valuable to add a section that describe the benefits of the sls approach and who is supporting it. ? --Beaucouplusneutre (talk) 19:13, 17 November 2011 (UTC)


 * I changed the section header to "Opposition and support" to provide a place for support text, but another user changed the label back without giving it a chance. :( -Fnlayson (talk) 18:28, 1 March 2012 (UTC)


 * How about "Opinion" or "Critique" with pro and con subsections?Doyna Yar (talk) 19:58, 1 March 2012 (UTC)


 * He could look like this one Minimum_wage --Beaucouplusneutre (talk) 12:10, 3 March 2012 (UTC)

Comparison, context, similarities to Energia
This has very striking similarities to the Energia system, the concept of using a space shuttle system's hardware for launching other things isn't unique. There are obvious differences too, like stretching out everything and making it taller, whereas the Energia just uses multiple generic strap-ons, and the main engines were always on the bottom of the big tank for the Buran, so in the sls they have to move them across.

I'm surprised it's not in the see also section, or used to provide some context for the article's subject. Of course I have no idea if anyone notable has commented on it, but for these kinds of inclusions, nothing is required. Penyulap  ☏  13:48, 19 April 2012 (UTC)


 * Adding the link in the See also section should not be a problem. But text comparing the two launchers needs to be cited so we don't get into Original Research land. The layout for SLS flows from the Shuttle and is similar to other Shuttle-derived launchers also. -Fnlayson (talk) 14:04, 19 April 2012 (UTC)


 * Comparison SLS vs. Ares variants and Direct's Jupiter proposal, which made a major pitch to the Augustine Commission, would seem more germane to the decisions that lead to SLS. Doyna Yar (talk) 18:12, 19 April 2012 (UTC)


 * I've added "Energia, a comparable launcher which carried payloads including Polyus and the Soviet space shuttle Buran." to the see also section.


 * I too thought that the see also section was a good place for it, I don't know where it has or has not been discussed notably, I simply do not have an interest in the subject. The other thing I was thinking would be context, as the Energia indicates to the readers that the concept has been used before, although the Energia was built from the start with the whole idea in mind, re, placement of engines and so forth. I figured if they are studying the subject of using the shuttle launch system (with the required mods) as a launcher, they may be interested. Penyulap  ☏  09:30, 1 May 2012 (UTC)

In line Shuttle and lamenting
I seem to recall at one time back in the 70's there was a proposed inline Shuttle/Saturn stack. I know their retired, but I can't help but wonder what an inline Shuttle/SLS stack would take. Now my personal interpretations of the STS retirement are what they are and I do not want to offend anyone or get into a long issue over them. I believe STS (along with other ISS hardware) was prematurely retired politically. They had a significant number of flights remaining on their airframes and upgraded avionics that could have potentially been utilized, manned or automated, for decades in it's previous configuration or possibly otherwise. Doyna Yar (talk) 04:58, 12 June 2012 (UTC)
 * But what would they do? It cost well over a billion dollars to launch TMV943 (talk) 02:26, 13 June 2012 (UTC)
 * Well for one thing large downmass, say in the event of a damaged ISS module that could be repaired on the ground. Nevermind just doing the orbital infrastructure work, ISS support, and science they had for decades. The shuttles had no destination until the ISS they were designed to service, now ISS is compromised from it's original vision with no crew hab and shuttle. The crew reduction from 10 to 6 meant a better than 50% reduction on science because the station requires the work of 3 just for maintenance. The shuttles were certified for 100 flights each, their frames could be modified for reuse on a new safer launcher like SLS. I can't honestly say what that may cost, but there are plenty of government bean counters who could do a cost/benefit analysis. If i'm not mistaken the military aid we give to Egypt and Israel just to buy the peace was better than the STS annual budget. I'm not suggesting the flight schedule they had, but wouldn't keeping one in reserve make some sort of sense? From strategic national assets to museum pieces, makes me wonder if they'll see Buran's fate.  — Preceding unsigned comment added by Doyna Yar (talk • contribs) 03:25, 13 June 2012 (UTC)


 * If you're going to use them, then keep two with the 2nd as a backup. The shuttle program seemed to have gotten costly with so many people supporting the program near the end.  I preferred keeping the Shuttle going, but it'd take good boost of funding for that, ISS, commercial space, and SLS development. -Fnlayson (talk) 14:48, 13 June 2012 (UTC)

I kindly remind you of WP:NOTFORUM: Either discuss improvements of the article or take this topic somewhere else.--Oneiros (talk) 19:47, 13 June 2012 (UTC)
 * Right. Thanks for the reminder. -Fnlayson (talk) 20:07, 13 June 2012 (UTC)
 * Welp, so much for that..., thanks guru. Reminds me of middle school. Delete at your leisure (how do you throw the bird again in ASCII?) Doyna Yar (talk) 03:51, 14 June 2012 (UTC)

Artist Concept picture with exploded view of elements...
I found an image released by MSFC on their flickr photostream I am sure that it could be used here, then again I don't know if the original artist has any rights or if it's all property of the US gov. Dreammaker182 (talk) 17:49, 23 July 2012 (UTC)


 * That's a  GO for LAUNCH  one eight two, it's public domain and you're all clear. Penyulap  ☏  17:59, 23 Jul 2012 (UTC)

Costs
I added a target cost just now. I did work out the implied launch costs (per pound) to LEO, which I hope qualifies as a trivial calculation. Noting that it is not fair to compare total program costs (including development) with marginal costs seemed necessary, and is probably uncontroversial, but could use an external reference. I hope one pops up in the current reliable media soon. NB Elron Musk quoted (if I recall) $100M for 53 mt of payload to LEO using the Falcon9 Heavy. I'm eager to see if that actually flies next year, as scheduled. Wwheaton (talk) 20:38, 13 September 2012 (UTC)
 * http://www.newspacewatch.com/docs/IAC-12.D3.2.3.x15379-NASAStudy.pdf, this study put the price at 65 000/kg for 70 mt sls and 40 000/kg for the 130 mt one.--Beaucouplusneutre (talk) 12:10, 24 October 2012 (UTC)

Block 0 ?, oh and 1B etc...
The article of date refers to a Block 0 configuration with 3 RS 25D engines, but there is no use or mission specified for it. I suspect this is an anachronism, that should be expunged if it has no further role in the program. Does anyone object to dropping this? Wwheaton (talk) 16:10, 11 September 2012 (UTC)


 * Looks like it was a planned version initially. Just note it is no longer part of the plan. -Fnlayson (talk) 17:01, 11 September 2012 (UTC)

Well it's been a while since I read it but there is references to a Block 1B alternative to Block 1A here; http://www.nasaspaceflight.com/2012/07/wind-tunnel-testing-sls-configurations-block-1b I never got around to any inclusion in the article. Any thoughts? Doyna Yar (talk) 03:21, 12 September 2012 (UTC)

I got Block 1B refs in finally... Doyna Yar (talk) 04:05, 1 December 2012 (UTC)

Senate Launch System
Because this is potentially volatile and could easily stray into POV violation territory, I'm posting this on the talk page first and asking if this could be added intelligently into the article somewhere and to start a discussion as to where this ought to be placed by those who have been maintaining this article.

As a derisive term applied to this rocket, the term "Senate Launch System" seem like something which should at least be mentioned in this article... either in the lead paragraph (as an "alternate name" per WP:MOS) or in the criticism section. For those who say find reliable sources, I'll give five:


 * http://arstechnica.com/science/2012/03/nasa-admin-returns-to-congress-to-fight-for-commercial-space/
 * http://www.huffingtonpost.com/rick-tumlinson/the-senate-launch-system_b_843607.html
 * http://www.nytimes.com/2011/09/15/science/space/15nasa.html?pagewanted=all
 * http://www.nationalreview.com/corner/278210/blame-congress-and-pork-not-nasa-rand-simberg
 * http://nasawatch.com/archives/2011/07/mike-griffin-is.html

The term has thus been used by multiple people in major publications and be considered reliable sources... including the primary title of two of those articles (notably those articles are already used as a source for this Wikipedia article). I don't think this fits WP:UNDUE as something to be ignored due to overpowering the article and should be inserted somewhere into the article in an intelligent manner. Indeed it is shocking to me that it isn't in this article except as a source title name... as if this article is being deliberately cleansed and censored to promote a particularly positive POV. Rather than fighting with an edit war, I'd rather some intelligent discussion about where it should be inserted happen instead. --Robert Horning (talk) 23:41, 19 November 2012 (UTC)


 * Most of those articles are from the fall 2011, over a year ago. And a couple do not seem to be from neutral organizations. What about more recent coverage from prominent news sources?  Maybe mention that name somewhere in the article, but not in the Lead as it is not common and significant enough.  It'd be POV to give a short term nickname undue weight there, imo. -Fnlayson (talk) 06:17, 1 December 2012 (UTC)
 * Sources do not need to be neutral. My point is that this is a name that has been applied to the system, and is in fact a face of the criticism being applied to the system.  Indeed it is pushing a POV to exclude this kind of information from an article of this nature, where it gives the impression that this is a puff piece and highly sympathetic towards NASA and the SLS contractors.  I'm not asking for undue weight as in making a major section going into depth with this name, but I find it disingenuous to suggest that this nickname doesn't exist either.  Each one of those sources would count as reliable sources in other contexts, so why not here?  --Robert Horning (talk) 07:41, 1 December 2012 (UTC)

Boosters
The wikipedia entry on the Rocketdyne F-1 engines links to a 2012 press release from Pratt & Whitney Rocketdyne indicating that they are developing a proposal for liquid-fueled SLS boosters of the same dimensions as the SRBs, but using a single F-1 engine on each booster. Should this be included on the SLS page? TechnicalBard (talk) 05:44, 14 August 2012 (UTC)


 * An updated F-1 engine is one proposed solution. NASA has not selected an advanced booster for SLS yet. -Fnlayson (talk) 14:53, 14 August 2012 (UTC)

C'mon NASA.. you KNOW we all want to see five F-1 engines in the first stage like the S-1C booster, with twin SRBs... just for one launch... please!!! — Preceding unsigned comment added by 146.1.2.18 (talk) 20:34, 23 October 2012 (UTC)


 * The F-1 proposal is for a booster rocket, not first stage. There should really be a good section on the upcoming competition for the boosters. It feels only hinted to in the current booster section. TMV943 (talk) 02:40, 24 October 2012 (UTC)


 * I am eager to see how the F-1 rocket engine booster comes along too, I am especially interested if they up-rate the engine to the F-1A thrust and Isp levels that were slated for flight testing on the Saturn V-3 of the late 1970s. Moreover, someone should resurrect the LH2/LO2 M-1 (rocket engine) for the 2nd stage(although the cluster of J-2X's might be cheaper but heavier). What's really needed to do a Mars mission right is a (NTR)nuclear thermal rocket - such as NERVA which was tested in the 60s, as you need high thrust crew transfers from Earth orbit to Mars (or to a NEO orbit) so your crew aren't bored to death out there waiting 8 months on Hohmann transfer orbits to Mars.
 * For cargo movement you're not too bothered by how slow it goes, you're just interested in launch costs$/kg so a nuclear electric rocket(NEP) might be ideal to serve as a tug boat between high earth orbit to Mars or a NEO. The NEP would be ideal to serve as a Earth to Mars tug boat that is frugal on propellant, easy to refuel when the need arises, and has a higher Isp(better mileage) but lower thrust(slow acceleration) than the NTR.
 * Boundarylayer (talk) 09:35, 2 April 2013 (UTC)

Deep Space Habitat (DSH)/Skylab 2?
Deep Space Habitat (DSH) is a credible NASA concept with it's own article, and may be part of the 'future' BEO architecture, but is NOT unto itself a SLS mission. All DSH missions listed are already referenced above. As of yet I do not think it belongs here. The Skylab 2 thing is flimsy at best and me being nice, and I'm not nice. I would suggest a better source or it's gonna be contested. This is why I don't post every *eyes rolling* Boeing proposal that comes down the pike if it doesn't have some tie in to NASA paperwork. This isn't a wishlist, It's supposed to reflect what we know about the 'roadmap' that is directly connected to SLS.Doyna Yar (talk) 03:22, 24 April 2013 (UTC)


 * The connections of those to SLS does seem weak. I had to look through the 2nd page of the Aviation Week article (ref. 67 now) to find a meniton of SLS in the text.  Maybe combine these with the Near Earth Asteroid (NEA) missions entry. -Fnlayson (talk) 03:49, 24 April 2013 (UTC)


 * If you want real speculative wish list material, see here - Falcon rocket vehicle.


 * As for this article, The Skylab II material is well referenced and due to the massive, large diameter propellant tanks required for a Skylab-esque station, it is a unique intrinsic capability that SLS will have over other vehicles like the Falcon Heavy. While the reference to the Deep Space Habitat(DSH) here is weak, it too should stay. Moreover in reference to 'wish lists', imagine for a moment if wikipedia was around when the Saturn V was being designed, it would be necessary to have the very speculative, but authoritative, contemporary Von Braun quotes about his 'wishes' to use the vehicle for Mars missions by no later than 1980 etc. etc. So I don't see anything wrong with including the material.


 * In saying that, I do understand your concerns, but they would be easily dealt with if someone were to just make clear that the DSH being carried skyward by the SLS isn't, obviously, part of the administrations firm 'roadmap'(seen as it doesn't really have a firm roadmap to speak of anyway), but DSH is, like lots of other things, merely being assessed in relation to the SLS.
 * Boundarylayer (talk) 03:51, 27 April 2013 (UTC)

Advanced Booster Competition Subsection?
I've been kicking this around for months. Does the ABC merit a subsection under the booster section and/or perhaps a separate article? Doyna Yar (talk) 04:08, 22 May 2013 (UTC)


 * I don't think that is needed, since the Advanced Booster is for the main SLS version, Block II. Summarizing the text in the Booster section better helps a lot. -Fnlayson (talk) 16:07, 23 May 2013 (UTC)
 * Not to disagree but I've read several articles over the past year on the subject, like testing. I see these articles mirroring the SLS and Orion testing (wind tunnel, test articles, mockups, drop tests, pad tests, etc.). The ABC is unique in that it still isn't fixed SLS hardware where as the core and second stage options are mapped out. Doyna Yar (talk) 02:59, 24 May 2013 (UTC)


 * That sounds right given things have moved slowly or been delayed on that. If the Booster section grows a lot more, we can we put the ABC content in a separate subsection from the current 5 segment SRB for the Block I/IA/IB versions. -Fnlayson (talk) 15:12, 24 May 2013 (UTC)

Payload capacity
The payload capacity cited in the article is 70 tons for Block 1 and 105 for Block 1A/1B, but according to this this document the Block 1 has a payload capacity of 90 tons to LEO and the Block 1B/1A a payload of 130 tons. I know that the real capacities are/were restricted for political reasons but now that there's a document with the real payloads, should the real higher payloads be mentioned in the article? — Preceding unsigned comment added by 217.123.143.19 (talk) 13:29, 20 July 2013 (UTC)


 * I don't see Block 1A or 1B mentioned in that presentation. Those payload masses could be potential growth capabilities, or they are counting Orion capsule and something else as the payload.  There needs to be more than one presentation with a meniton of the payload to say the payload masses have officially changed. -Fnlayson (talk) 16:22, 20 July 2013 (UTC)


 * I was wrong about 1A and 1B, sorry about that. But shouldn't the article at least make a mention of Block 1's higher estimated payload capacity? Ed Kyle's space launch report also estimates Block 1's payload to LEO at 95 tons.(217.123.143.19 (talk) 12:55, 26 July 2013 (UTC))

SLS Vehicle Configurations
Hey... any chance we can get the graphic for the SLS Vehicle Configurations repeated on this page more then just the two time it already is? I mean... it really doesn't do the graphic justice only posting it twice. Maybe we can sneak it in to another section of the article just to make sure that readers don't miss it. — Preceding unsigned comment added by 158.15.255.228 (talk) 11:37, 18 August 2013 (UTC)
 * ✅ - It's now on the page five tim... ok, it's only on once now;). &mdash; Gopher65talk 18:07, 18 August 2013 (UTC)

Incoherent writings
"Mars Society founder Robert Zubrin suggested that a heavy lift vehicle should be developed for $5 billion on fixed-price requests for proposal, finance issues aside, in the same breath however Zubrin also stated that he does not agree with those that say we don't need a heavy-lift vehicle, and stated "We absolutely do need heavy-lift".[56]"

This comment is grammatically nonsensical. Going off of that text alone, it does not follow that if one suggests developing a new booster it means they wish to see heavy lift capacity fail (though it is admittedly unclear what the writer was actually trying to say). I suggest rewriting it as:

Mars Society founder Robert Zubrin suggested that a heavy lift vehicle should be developed for $5 billion on fixed-price requests for proposal. Zubrin also stated that he does not agree with those that say we don't need a heavy-lift vehicle, and stated "We absolutely do need heavy-lift".[56]

This is internally consistent and the two sentences are not in disagreement.

I see this kind of stuff a lot on wiki and it makes the articles hard to read, which makes people go somewhere else.

174.131.5.205 (talk) 00:57, 20 August 2013 (UTC)
 * ... so do it:). The absolute worst that would happen is that someone would revert your change. Please feel free to make whatever improvements you deem necessary. I'll make this edit for you to get the ball rolling, but you can do it yourself as easily as write it here. &mdash; Gopher65talk 03:34, 20 August 2013 (UTC)
 * ....concur, GO!, be gone. Contribute or vaporize Doyna Yar (talk) 03:45, 20 August 2013 (UTC)

Block II version using ATK's "Dark Knight" SRB
The editor User:Fnlayson continues to assert their false beliefs in the article. They write in the edit history of September 10, 2013 "Remove overlinking, trim overly wording descriptions, and corrections. Block II uses Advanced Boosters, not SRBs. Further details should go in the linked articles."

However they are clearly wrong, there is an advanced SRB proposed for Block II. READ -> http://www.nasaspaceflight.com/2013/01/the-dark-knights-atks-advanced-booster-revealed-for-sls/ 86.46.186.19 (talk) 20:33, 10 September 2013 (UTC)


 * The 5-segement SRB used on SLS Block I is not the Advanced Booster on SLS Block II. NASA plans to use Advanced Boosters for Block II (see NASA fact sheet).  The ATK Advanced Booster is not the Advanced Booster for Block II, unless[/until] it beats the F-1B booster, and other proposed ones in NASA's booster competition. -Fnlayson (talk) 21:35, 10 September 2013 (UTC)


 * I am aware that the block I, ~70 MT to LEO, SRBs aren't the same as the proposed Block II, ~130 MT to LEO, advanced SRB, as the latter is termed the advanced SRB going by the preliminary name "Dark Knight". However you edited the booster section to remove any mention to an advanced SRB being in the running for block II.
 * Now you're largely just stating the obvious here with your reply and not acknowledging you were in serious error. In fact you still are in error, seen as you, yet again, just removed mention to this Block II 130 Metric ton advanced SRB for the second time. Moreover you are wrong here in your reply, the Thiokol/ATK advanced booster IS indeed an advanced booster in the Block II competition.
 * Do you need me to walk you through this again?
 * 86.46.186.19 (talk) 22:17, 10 September 2013 (UTC)


 * I listed the ATK Advanced Booster as competing with the other proposed Adv. Boosters in my post above. Block II currently has Advanced Boosters, which are placeholders until one of the proposed boosters is selected. -Fnlayson (talk) 22:34, 10 September 2013 (UTC)


 * No you did not list the ATK's block II advanced SRB competitor in the article, you removed all mention to it. Now in your most recent edit of the article you tacked on mention to ATK's block II "Dark Knight" advanced SRB to the end of the booster section in the most ad hoc of manners, without listing any performance data or putting it in context. Don't worry though, I fixed that.
 * 86.46.186.19 (talk) 23:23, 10 September 2013 (UTC)


 * The source does not provide thrust for the Adv. ATK booster or I would have mentioned that too. It only says "provid(ing) NASA the capability for the SLS to achieve 130 mT payload with significant margin", which has been added. -Fnlayson (talk) 23:27, 10 September 2013 (UTC)

Yes the initial source I provided does indeed only say that. However I should have presented the one more detailed one below. As I know ATK's advanced booster can only achieve the Block II requirement of 130 metric tons to LEO, IF and only IF, the number of RS-25s/ core Hydrolox engines, are increased from the planned 4 to ATK's desired 5. So it is not at all fair to present the article as you have done so. Comparing apples to oranges, as with just 4 RS-25 engines they will only be able to lift 113 metric tons. See the performance data from the horse's mouth, that little gold triangle means they require a change of the core stange to five RS-25 engines to achieve 130 to 138 metric tons - http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=30862.0;attach=515287;image In sum we need to rewrite the booster section, as it's getting pretty ridiculous the amount of times you keep on inserting misleading info. 86.46.186.19 (talk) 00:00, 11 September 2013 (UTC)

Metric Tons
This is a likely source of confusion and disagreement, so I think it would be helpful to explain Wikipedia policy explicitly. Whenever SI units are used (including "non-SI units officially accepted for use with the SI" like the tonne/metric ton) Wikipedia policy as given in UNITS requires that they are given the correct symbol. This applies regardless of context, with only a few exemptions such as "cc" for engine displacements. SI symbols are not abbreviations; they are language-independent symbols like mathematical and musical notation, designed to be understood by anyone regardless of language; they are used even in languages that are not written in the Latin alphabet, as well as languages that use completely different names for the units. Moreover, there is by design a one-to-one correspondence between symbol and unit, to avoid ambiguity - the only correct interpretation of the symbol "70 mT" is actually "70 milliteslas" which is obviously not what is meant. Language-dependent abbreviations of unit names, such as "kph", "cu. m.", "mtrs", "mT" and so on, are likely to cause confusion, they are strongly discouraged by the BIPM and the NIST, and they are against Wikipedia style policy. Archon 2488 (talk) 22:19, 22 September 2013 (UTC)


 * Agreed, I found it quite frustrating why Fnlayson took it upon himself to vandalize the page on september 18th 2013 with the changing of the Low Earth orbit payload figures, from being displayed in words with "metric ton", to his desired "70 mT" & "130 mT" symbolism.
 * 86.47.66.149 (talk) 06:02, 24 September 2013 (UTC)
 * No need for accusations. Honest misunderstandings/mistakes are not vandalism.  I used a common abbreviation for metric ton to match what is a quote in the article. -Fnlayson (talk) 09:50, 24 September 2013 (UTC)

Configuration layout
The current layout described the core stage, boosters and upper stages in a somewhat confusing and cluttered manner. Would it be better to remove these sections and instead give each configuration (Block 1, 1B, etc.) it's own section? I'll try to write something soon but I thought such a radical change should be discussed first. M129K (talk) 12:16, 23 September 2013 (UTC)


 * I was thinking about doing this as well. I would be glad to help you write sections for each configurations. The current layout is fine, but lacks detail that I would be happy to assist in adding. --HarderResearch (talk) 00:40, 11 October 2013 (UTC)

Design and Development
The section on design and development begins with the announcement by NASA of design selections. This is plainly not the beginning of the program, which would have begun with solicitation of designs. Thus the section is incomplete; it assumes the design process instead of informing about it. Dismalscholar (talk) 08:10, 27 November 2013 (UTC)

Radiation hazard needs to be quantified
The following addition to the picture attached was deleted as "irrelevant" by the previous editor. However I can't fathom why someone would think a ~1 Sievert to and fro radiation exposure to crew would be deemed "irrelevant". The length of the chemical propelled MSL mission was approximately 8 months, 240 days, the graphics 180 day estimate is based on readings from this mission. It is relevant to the choice of the upper stage engines of the crewed Mars transfer vehicle if they are propelled by slow chemical engines or something comparatively exotic that could do it in 180 days or less.


 * I didn't remove it, but I'm guessing that they said it was irrelevant because that's not what this article is about. It's not about a Mars mission, it's about a rocket. That image would be a great addition to the various crewed Mars mission articles (and there are many of them). The Mars One article would be a good place to start, and move out from there. &mdash; Gopher65talk 01:30, 22 February 2014 (UTC)
 * Right, there nothing in the caption that really ties it to SLS and the figure would better fit in another article, imo. -Fnlayson (talk) 03:21, 22 February 2014 (UTC)


 * I put it in the criticism section of this article, on an in-development rocket/launch vehicle, because as a Mars mission is likely to be on the cards for the Block II of the SLS, the choice of engines on the vehicle for mars transfer is important. If they go with chemical engines without an ability to do high delta V changes in velocity, then the crew will be exposed to a fairly high, some might regard, unacceptable risk. Are you guys saying that if I pull in a reference that deals with the radiation hazard as a factor on the choice of engines for the SLS upper stage, mars transfer vehicle then I can flesh it out in the article?
 * Like this, round trip with NTR nuclear thermal rocket engine estimated to be as low as 200 days, therefore 1 way transit about 100 days.
 * Total interplanetary trip time is dependent on how long the astronauts stay on the surface of Mars, most design studies with the shortest trip time have them staying no more than 20 days.
 * https://web.archive.org/web/20090302093708/http://www.inspi.ufl.edu/news/UF%20RESEARCHERS%20NUCLEAR%20POWER%20WILL%20MAKE%20MARS%20TRIP%20SHORTER,%20SAFER.htm
 * and this https://web.archive.org/web/20081011124255/http://www.fas.org/nuke/space/c07sei_4.htm
 * http://ares.jsc.nasa.gov/HumanExplore/Exploration/EXLibrary/DOCS/EIC031.HTML
 * Alternatively a chem propulsion CPS would result in a total of 365 days incl return. http://www.astronautix.com/craft/marion88.htm
 * 83.71.31.172 (talk) 23:49, 24 February 2014 (UTC)

Criticism section
It's not our job to deconstruct published criticism, just to record it if relevant. The critisicm section looks to be pretty well cited and referenced, and as a government program, published criticisms from industry figures ARE relevent and noteworthy. Recording that there has been critisicm of the program does not affect the article's NPOV, therefore I have removed the rewrite tag. Jmackaerospace (talk) 15:11, 24 August 2014 (UTC)
 * That's not the point of the tag. The coverage in the section is unbalanced.  See the previous posts above and on the archive page. -Fnlayson (talk) 15:42, 24 August 2014 (UTC)


 * the above is OR it has nothing to do with the content of the article. If you think the critisizm section is unbalanced, please tag it to be re-written for greater balance - the current tag asked for it to be integrated wih the main article, which would mess up the NPOV of the whole article. Sorry for spelling, using phone, buggy. Jmackaerospace (talk) 08:52, 25 August 2014 (UTC)

Right, I have added a section POV template which is more in line with what you seem to think is the problem. Suggest you read Criticism_sections because as previously stated, I can see no problem with this section as written.Jmackaerospace (talk) 09:36, 25 August 2014 (UTC)
 * That's fair, and I've read that times before, but not recently. In practice, Criticism sections can become magnets for negative coverage without balance.  This section was discussed in the 'Neutrality' in the archives ~2 yrs ago and edits/changes were made.  But there's still no counter arguments and primary sources are heavily used. -Fnlayson (talk) 15:33, 25 August 2014 (UTC)

Initial Launch date window pushed back
Just so everybody's aware, it looks like NASA's pushed back the initial launch date of the Block 1 SLS to November 2018, and that has the potential to push back all the subsequent mission dates as well. I haven't changed anything in the article, as the source below doesn't give a definite date that it's pushing to. You can read the article below: http://news.yahoo.com/nasa-says-heavy-lift-rocket-debut-not-likely-230603632.html — Preceding unsigned comment added by The.famous.adventurer (talk • contribs) 09:51, 31 August 2014 (UTC)
 * That date is already listed in the mission table. The delay just means that the end of the window for the launch was extended to 2018.  Late 2017 is still the working date according to a Aviation Week article on this. -Fnlayson (talk) 12:14, 31 August 2014 (UTC)

SpaceX HLV
While SpaceX respectfully is making great strides in the industry, their HLV is very much on the vaporous drawing boards and far from even a prototype. In time it may be relevant, but I don't think it belongs here at this time. Doyna Yar (talk) 02:57, 31 August 2014 (UTC)
 * The SLS is vaporware itself. Even odds that the next president cancels it, or that the Tea Party (which hates it), gains enough sway in the House to slash its funding. The SpaceX BFR is a good decade away though, so it's vaporware as well. But we write articles about vaporware, as long as it's notable in the media. And I'm certain the SLS qualifies, and the BFR probably does, too, even though it's at an earlier stage of development. &mdash; Gopher65talk 03:09, 31 August 2014 (UTC)
 * I guess my 'vapor' usage hit a nerve. My point simply is SLS is under fabrication and quite tangible regardless of political speculation at this time. The SpaceX HLV isn't beyond the conceptual. Because someone journalistic draws some kind of speculative competitive relation to fluff up an article does not make it relative especially when SpaceX confirms no intentional competition with SLS. You may as well include the Long March 9 130K LEO rocket as well which is just as conceptual unless I'm right and that too is not relevant at this time. Of course under the right political environment it could be postulated Americans could go to Mars on a Chinese HLV. Pardon if I don't hold my breath. You can't have it both ways. For now this is an article about the SLS program. I view the comparison as of today as tabloid. Aside all that I don't see a class comparison between 53,000 to LEO and a base of 70,000 LEO that is planned to expand to 130K and remotely 150K. That sounds like different rocket classes to me. If and when SpaceX begins real world development of their HLV and when NASA or Congress would consider it an alternative to SLS it becomes relevant to the article. I would accept their HLV may become complimentary to the NASA roadmap, but no substitution for SLS. Move it to See also. For what it's worth that's my opinion. Doyna Yar (talk) 03:26, 3 September 2014 (UTC)


 * There are no plans to expand the SLS to 130 tonnes. Block II has been put on indefinite hold. (To give you an idea of what "indefinite hold" means at NASA, both VentureStar and JIMO are on indefinite hold. And they always will be.) Not only is it not under development, it isn't even planned to be under development. So this isn't a 130 (or 150) tonne to LEO rocket. It is a 70 tonne to LEO rocket that has one planned launch (which might, *might* occur in 2018... maybe), and might have one additional launch in a 90+ tonne to LEO configuration. Maybe. Few "in development" rockets have ever been as vapourware as the SLS. &mdash; Gopher65talk 02:48, 4 September 2014 (UTC)


 * If you are sure you are correct please feel free to blank any sections of the SLS article that doesn't fit your narrative. I promise 'I' will not revert any of your edits. Have fun with that. Please don't bother replying- I just stated my opinion, it's not a conversation... do what ever you want. Doyna Yar (talk) 03:45, 4 September 2014 (UTC)

I don't think that "hitting a nerve" with comments on the Talk page is very relevant. A media source has noted that there may be some competition for American HLV vehicles, and possibly two of them, in the 2020s. The brief mention of that currently in this article does not seem unduly weighted, is verifiably sourced, and seems to state only that basic fact. After all, neither vehicle is flying today, both are only in early stages of development with flight years away. So given that Wikipedia is not censored, I would think it quite appropriate to leave the mention of the competitive vehicle in the article. Cheers. N2e (talk) 04:15, 6 September 2014 (UTC)


 * It does strike me as undue weight that a single paragraph with a single source should have a first level heading devoted to it, though. Especially since SpaceX goes out of their way to disavow any competition with SLS. Maybe when we get more solid details about BFR, but a heading on "competition" seems very premature.  A ( Ch ) 05:12, 6 September 2014 (UTC)


 * That makes sense. Where do you propose it goes?  Since it does not seem to fit under any of the other headings, and is not appropriate for the lede, is there some other section heading under which this (and possibly other material too?) could fit under?  N2e (talk) 13:39, 6 September 2014 (UTC)


 * Honestly I think it's too early to be included at all. We don't have solid information on BFR yet. Even the NSF article doesn't include any specific way in which SLS and BFR would compete - it's a history of SLS followed by what we know/speculate about BFR. Of course as a spaceflight enthusiast I'm rooting for SpaceX to make Mars happen, but we can't compare the merits of the vehicles because we don't know enough about BFR. We can't say they're competing because what're they competing for? We can't say one is cheaper than the other because who knows? An NSF article making vague remarks about competition doesn't tell us anything about SLS. Let things play out, then we can say what, if any, effect BFR has on SLS and vice versa. Until then it seems to me that anything other than a one sentence mention somewhere that SpaceX is planning on building a rocket with similar lift capabilities to SLS is giving undue weight to the issue. Of course I hope that changes if SpaceX really does what most of us hope it will, but right now there's really not much to say in an article about SLS, and certainly no competition to speak of.  A ( Ch ) 16:44, 6 September 2014 (UTC)
 * Yikes I ramble when sleep deprived. TLDR I concur with SkywalkerPL.  A ( Ch ) 20:55, 6 September 2014 (UTC)


 * It even needs to be there? Space Launch System got already covered a topic of SpaceX and a fact that Falcon Heavy is the competitor. I say: Remove whole section. It's completely redundant. SkywalkerPL (talk) 16:10, 6 September 2014 (UTC)


 * Well it clearly doesn't need its own top-level section, but I don't believe removal is the right thing to do. It's clearly verifiable, and Wikipedia is not limited by disk space, nor censored.  The idea of political competition between the two in the American politico-sphere is clearly noteworthy.  So I'm thinking it might fit somewhere in criticism or in political considerations.  Cheers. N2e (talk) 19:38, 8 September 2014 (UTC)
 * That sounds about right. I wouldn't give it undo consideration though. Maybe one sentence. It is, after all, not a real rocket yet. &mdash; Gopher65talk 23:37, 8 September 2014 (UTC)
 * Look at the comment from Anythingcouldhappen up above my. One that starts with "honestly I think it's too early to be included at all". Other than all of the arguments mentioned there - the article in source for this section is mostly original research of its auther with rather poor factual background supporting said conclusions instead opting for using self-references and building content on a base of some posts from the NASAspaceflight forum. I'm very concerned that this section doesn't fulfil the criteria of Verifiability. As I said earlier - it's redundant to the #Criticism section in its verifiable and objectively true points. SkywalkerPL (talk) 10:04, 9 September 2014 (UTC)

Funny, no mention, debate, or issue in the Falcon Heavy page. Hell not even a mention of SLS..? Hint and a half if the SpaceX junkies aren't playin' it up you're not getting enough oxygen citizen. Just add Falcon Heavy's page to See also and lets just wait and see. Yeesh! Doyna Yar (talk) 03:20, 9 September 2014 (UTC)
 * If you have any sources that can counter the arguments in Space Launch System section then feel free to provide them - this article is in a desperate need for them. SkywalkerPL (talk) 10:04, 9 September 2014 (UTC)

I don't believe any sort of full consensus was reached in the above discussion on what to do with the "Competition for an American heavy-lift launch vehicle" section of the article, although there were some elements of agreement. Moreover, much of the discussion above was not even about that section, which started this discussion, but about other topics, including "Criticism" of the SLS and how the much-smaller Falcon Heavy may or may not compete with the SLS. While these may be relevant topics for the Talk page, they should be discussed in some separate section, not in the section discussion "competition" that may emerge in the 2020s from the MCT and SLS.

Just today, I observed that someone made a rather major edit based on a "suggestion" made in the above section, but which did not have widespread consensus. I have added that deleted material back into the article, and have started a discussion below, per WP:BRD. Please join that discussion if the topic of "competition" or the "MCT and SLS as both being >100 mt launch vehicles potentially available from American producers in the 2020s" interests you. Cheers. N2e (talk) 05:35, 23 September 2014 (UTC)


 * It did not have a consensus? As far as I see - it did. No new arguments were presented against removing the content, and these concerns that appeared - were already addressed and no new opposition against it was posted. As far as I see - changes made by User:Fnlayson were fully justified. Restoring. SkywalkerPL (talk) 10:59, 23 September 2014 (UTC)
 * Ok, I just noticed you, N2e, posted stuff in a new section. Please, keep everything in one place. I moved it below as a subheader. Discussion on topic should stay here, otherwise it's way too easy to miss. SkywalkerPL (talk) 11:05, 23 September 2014 (UTC)

BRD discussion on recent deletion
I have added back a section that was deleted in an edit on 14 September 2014 by User:Fnlayson. I assume good faith. Suggest we discuss it further here, per WP:BRD, and see if perhaps smaller changes can't be proposed and consensus obtained.


 * I do not believe that a consensus existed on this Talk page for such a radical change. See discussion above in Talk:Space_Launch_System, from 31 Aug thrugh 9 Sep 2014.
 * I do not think that the emergence of another Super Heavy Lift Launch Vehicle on the American scene is in any way a criticism of the Space Launch System, so in any event, the material here would not fit in the "Criticism" section.
 * I do believe that some changes could be made to improve that section, and perhaps keep it from being in a "==Section heading==" -level section. But unfortunately a subsection of the existing "Criticism" section is not going to work, since in no way is the material in that section related to any criticism of SLS, by any identifiable person or persons or company.  The article even says SpaceX has gone out of their way to avoid placing the MCT in direct comparison with SLS.  It seems to be media analysis that have begun to do so here.
 * I don't believe the existing section overstates the case. The prose is merely noting that "... media sources have noted that the US launch market may have two competitive launch vehicles available in the 2020s to launch payloads of 100 metric tons (220,000 lb) or more to low-Earth orbit. The privately-funded SpaceX MCT launch vehicle powered by nine Raptor engines, has also been proposed for lofting very large payloads from Earth. While SpaceX plays down the competitive aspect with SLS, if SpaceX makes progress on its super-heavy launch vehicle in "the coming years, it is almost unavoidable that America’s two HLVs will attract comparisons and a healthy debate, potentially at the political level".  This seems, to me, a rather measured and limited statement about an indubitably verifiable item.

So to start with, how might we incorporate this material on this competitive aspect into the article, as some subsection that doesn't imply it has anything to do with criticism?

Cheers. N2e (talk) 05:27, 23 September 2014 (UTC)


 * As per my previous post:
 * Consensus was reached - remove the content.
 * On the contrary, there was no consensus in the section above this BRD subsection to remove the content. For example, when the topic was, as it started out, the MCT launch vehicle potentially providing competition in the 2020s for the >100 mt version of the SLS, you can clearly see the lack of consensus right in the first four comments.  Later on, the discussion became less tight when it was widened in comments by a couple of editors who added a different topic (Falcon Heavy, and competition in the considerably-under 100 mt sector of the launch vehicle classes), and a different section of the article than had been discussed in the previous half-dozen posts (the one entitled Competition, not the one that at the time was entitled Competition for an American heavy-lift launch vehicle).  However, a wider discussion, with unhappiness about emphasis of Falcon Heavy etc. in some entirely different article section, albeit expressed by a couple of editors, does not make a consensus to remove the content on competition of a different launch vehicle in the >100 mt segment in the 2020s.  N2e (talk) 11:36, 25 September 2014 (UTC)


 * It's not a matter of criticism or not, it's a matter of verifiable content, and as both: me and  A ( Ch ) tried to point out - this section doesn't fulfil the criteria of Verifiability and it's too early to include a section like that even if we'd assume that this section is suppose to be included at all.
 * One opinion doesn't make a "media analysis". And as  A ( Ch ) rightfully pointed out - it's whole lot more complicated than you try to make it in your reply.
 * Read previous discussion, it was already addressed. It's a whole section, not a `mere note` as you suggest, and.... read below (Falcon Heavy is already mentioned in the article).
 * I don't know what sort of bad blood may have been going on in this article, or this Talk page, for some time; but I know I haven't been involved with it, and am not even aware of it. As I noted above, the discussion of this section, and the couple of sentences added to the article about the potential competition in the >100 mt sector, in the 2020s, from the MCT launch vehicle, has nothing whatsoever to do with the Falcon Heavy.  I don't really understand how that got conflated in the discussion.  But it does seem to me that some sort of ongoing argument(s) of editors that had been going on for some time got added to the much smaller scope changes and discussion about 2020s competition in the >100 mt space.  N2e (talk) 11:36, 25 September 2014 (UTC)
 * "So to start with, how might we incorporate this material on this competitive aspect into the article" - I don't see any point of incorporating it.
 * Let's tear it apart for a moment:
 * First sentence - fact that Falcon Heavy is related to SLS is already addressed by the article, so it's nothing more than a duplicated content. Other than that maybe I'm missing something but the source doesn't mention anything about other "media sources" that would "note" anything about the "100 metric tons" launch vehicles - it's completely unsourced statement.
 * Second sentence is just an advertisement of SpaceX, irrelevant to the topic.
 * Third sentence is a private opinion of a few NASASpaceFlight forum members (which is directly pointed out in the source itself + the fact that an author is one of most notable members of that forum). Unless it can be verified by independent sources (other than the forums) to actually show that is has anything to deal with "media analysis" (as opposite to personal opinion of one forum member) - it should be removed. Also: refer to my comment from 9 September 2014. If you can find sources confirming statement in this sentence - it can be incorporated into the criticism section (which already mentions debates) with proper sourcing.
 * Your bullet list here illustrates my point. The discussion of the Falcon Heavy and the under-60 mt competition provided by that with the lower-end/initial 70 mt SLS in the 2010s somehow got conflated into an entirely different discussion.  Apparently, there is some sort of a deep history around these parts with arguments about Falcon Heavy.  I have not been, and am not now, involved in any of that.  The original change being discussed in this section was about a few sentences added to the article about an entirely different LV in the >100 mt sector of the space a decade from now.  N2e (talk) 11:36, 25 September 2014 (UTC)
 * I don't see how it fulfills Wikipedia quality standards to the point where you'd want to keep it in the article. I understand it mentions private aerospace company so it's related to your interests, however you shouldn't allow your personal point of view to interfere with objective verification of the content. SkywalkerPL (talk) 11:49, 23 September 2014 (UTC)
 * Careful here. I think you are treading on thin ice.  I suspect you know that we should be discussing content, not editors as we endeavor to improve the encyclopedia.  I think I can say with certainty that this is what I have been doing.  Casting aspersions on another editor's motive may be viewed as a personal attack, and in any case only detracts from the substantive discussion.  If on the other hand, you believe any editor is violating Wikipedia behavioral guidelines, then the place to take that up is at WP:ANI.  N2e (talk) 11:36, 25 September 2014 (UTC)
 * I read your reply (all parts of it) and all I see is discussing editors, not content. You added nothing constructive on a topic. If you'd like to address any points - please do, because in this latest reply of yours I don't see you addressing anything other than people taking part in the discussion and quoting Wikipedia rules we'll all aware of. SkywalkerPL (talk) 11:43, 25 September 2014 (UTC)


 * The MCT text was only shortened to a sentence that the source covered and put with the other SpaceX text as suggested above (after proposed Falcon XX heavy launch vehicle, which seems related). The Criticism section probably does need a more general name, like "Criticism and alternatives" to match the content there. -Fnlayson (talk) 13:47, 23 September 2014 (UTC)
 * —regarding your specific suggestion about broadening the name of the existing Criticism section to reflect the full scope of what is discussed there, that is a good idea, and I would certainly support it. Moreover, it would narrow the breadth of the substantive discussion on which editors may disagree here.  So if that clarification is not controversial to others, then once it is made, it certainly will make the other conversation smaller by one issue.
 * Fnlayson—I see you have made a change to the second-level section heading, to Competition and alternatives. I support that change!  And with that change, assuming in sticks, then any discussion of the MCT LV offering some sort of competition for the >100 mt super-heavy launch vehicle segment in the 2020s would clearly now fit somewhere within that section.  Thanks.  N2e (talk) 11:36, 25 September 2014 (UTC)


 * I will make a substantive response on the broader set of topics under discussion by SkywalkerPL when I have some time to address the several issues he mentions. N2e (talk) 16:56, 23 September 2014 (UTC)
 * I finally got back here and made those comments today, and inserted them inline, as this entire section seems to have become muddled, and is discussing a number of topics that have nothing to do with the original small amount of prose in the article about the potential competition in the >100 mt segment of the LV space in the 2020s. N2e (talk) 11:36, 25 September 2014 (UTC)


 * Is there a precedence for something like that? Usually alternatives are put simply in a bulleted list of "comparable rockets". What you are suggesting is a very clever compromise between "let's devote a section to SpaceX" and "let's not" but I don't see a reason why SLS article should put so much pressure on the fact that SpaceX might or might not have an alternatives - it's an article focusing on SLS after all, isn't it?


 * If anything - I would suggest adding Comparable rockets section similar to Delta II made of rockets from #See also plus additional Falcon XX (proposed) on the list along with whatever else is missing. References can be added where applicable.


 * I see absolutely no reason why so much pressure should be put on SpaceX ideas in this article as opposite to any other rocket. Perhaps I'm seeing bias that doesn't exist on a wikipedia, but somehow none of the articles about SpaceX rockets got anything remotely similar to what's being discussed here nor even the section about Falcon XX mentions anything about how it's threatened by a competition from SLS, or actually - it doesn't mention SLS anywhere at all. I'm honestly surprised one one-sided this whole thing is. SkywalkerPL (talk) 18:24, 23 September 2014 (UTC)
 * I see where you're coming from, but other articles don't mention the SLS as a competitive threat because, well, it isn't one.


 * Estimated SLS costs, including first 4 flights: 41 billion dollars, not including the Ares V development costs that weren't transferred to the SLS, even though Ares V tech is being used on SLS (it's literally, literally one of the proposed Ares V lite variants, just renamed). That does however include Orion, and some launch pad upgrades (estimated 2 billion). These are NASA's own internal predictions, so they're probably fairly accurate, if a little on the optimistic side. They usually undershoot the actual costs by a bit.


 * Estimated BFR costs, including first 4 flights, based on (likely very optimistic) SpaceX past statements: 2.5 billion + 500million*4 = 4.5 billion.


 * The costs are not in the same league. Both 41 billion and 4.5 billion are likely underestimates, but it's pretty clear even from those estimates that the BFR (if developed) wouldn't have to worry about any competition from the SLS. That's why no one ever writes articles saying "SLS is going to kill off BFR", but an article comes out every month saying "BFR is going to kill off SLS".


 * Personally I don't think that BFR deserves much mention in the media, because it hasn't even been announced yet. But it has been mentioned, and often. Remember, we aren't here to judge what people are thinking, we're here to report it in any unbiased way. And the unbiased report on this subject is this: everyone in the community is wondering whether SLS will even launch (NASA engineers are reported to be rooting against it, because they think it's a waste of money and their time... they want to be working on something cool like Nautilus-X). And if it does launch, the general bet is that it will only launch once, maybe, MAYBE twice before it's killed off. At an estimated 1.5 billion per launch (~20 billion per launch including dev costs), it's not going to get many launches. That's what everyone is thinking, and that's what the media is reporting, so that's what we write here. &mdash; Gopher65talk 23:05, 23 September 2014 (UTC)


 * Is anyone else getting a headache? "other articles don't mention the SLS as a competitive threat because, well, it isn't one." *Homer* 'doh!' Apples and oranges. Captain Obvious, wasn't that my whole point all along? I can't believe I'm adding anything to this argument again. One article with a whole lotta supposition by the author and absolutely no support from anyone in the industry public or private does not cut it. I have no problem with the article saying vaguely something along the lines that there may be 'some' future private competitor when SLS comes online. But until that is tangible or at least more broadly speculated by the media it's a joke. I still say just have a 'See also' link to the spacex rocket proposal and wait. That's my uneducated 2 cents and you are all welcome to take it any way you choose. I'll have nothing to do with the editing on this issue. Doyna Yar (talk) 04:04, 24 September 2014 (UTC)


 * We already have arguments you mention in the article. But everything has two sides of a coin and as I said - somehow the other one isn't presented. You think that SLS isn't a threat to SpaceX ideas of replacing it with Falcon derivatives? I found a source to prove contrary in 30 seconds: http://www.americaspace.com/?p=34964 . And as I said - somehow none of the arguments for SLS are mentioned anywhere - neither in this nor on any of the SpaceX articles. Besides, let's face it: we're comparing a rocket that's in final stages of it's development against what's either still in a design work (Falcon Heavy) or just an idea that didn't even go through preliminary studies (Falcon XX). SLS will launch - it's already pretty much closed case. As for the future beyond that - it's pretty much all just a pure speculation with little to none data supporting it, regardless if you think that SLS will have successful career or it'll be launched just once. And never say "That's what everyone is thinking" unless you have an actual sources to support it. Pulling statements like that out of nowhere stands against multiple polices on Wikipedia including Verifiability, No original research and Neutral point of view. SkywalkerPL (talk) 07:54, 24 September 2014 (UTC)


 * A few points:


 * 1) Again, this isn't about what we think, but rather specifically industry (spaceflight industry) opinion on the subject. In other words, expert opinion. That's not any of us here, and even if it were, we can't do OR (at least not on pedia:)). Since Wikipedia favours secondary (media) sources over primary (press releases, or statements from company officials/NASA), that ends up meaning this: "hmmm. There are 99 main stream media articles favouring this opinion, and 1 article on this one. Therefore we'll weight 99% of this section of the article toward the opinion favoured by 99% of the articles".


 * 2) Falcon X and Falcon XX aren't real, and never were. They were nothing more than an offhand comment years ago, by one SpaceX official. They never even made it to the paper rocket stage of development. They also aren't what people are discussing when they talk about a SpaceX BFR.


 * 3) The BRF is under active development. Its engine components are already being tested, in fact. So there is actual hardware. About the same amount of actual hardware as exists with SLS currently, in fact (very little for both rockets. That's why I refer to both of them as paper rockets). BFR (a rocket whose name hasn't been released, so the community (and SpaceX, actually) call it "Big F***ing Rocket") is a 200 tonne to LEO rocket. Publicly released details are scant, but point to a rocket powered by a giant staged combustion methane/LOX Raptor engine, with a 14 meter core (huuuuuuuuuuuuuuuuuge. Way bigger than it needs to be IMO). Not much else is known.


 * 4) The Falcon Heavy will launch in about 6 months. Final hardware is already either done, or nearly done.


 * 5) And finally, I disagree with the weight given to the BFR in the media. It is not a real rocket, and should receive only the most minor of discussion in the media until it is at the very least publicly announced by SpaceX. But I'm not the one writing all those articles:P. The fact is that BFR has been mentioned, and far, far too often. I wouldn't have written an article about BFR at all yet, but it's been mentioned too many times in the media to ignore. &mdash; Gopher65talk 13:00, 24 September 2014 (UTC)
 * There's actually one other strong reason that I forgot to mention why SLS can't complete with any commercial rocket, not just SpaceX's unnamed paper BFR. By law, if a cheaper American commercial alternative exists that can launch NASA payloads, NASA is *required* to give preference to it over their own rockets. Anyone, ULA included (the most expensive commercial launch provider in the world), can develop an SLS alternative that will launch for less than 1.5 billion a flight. If *anyone* flies a rocket that can carry NASA payloads cheaper than SLS, NASA will have no choice but to use it.


 * In the real world, I suspect politicians could weasel their way around that law if they had to. &mdash; Gopher65talk 00:08, 25 September 2014 (UTC)
 * Yes, it's about what the industry thinks, that's why all of the points of view need to be represented, not just one. And it's nowhere near to 99 vs 1 opinions split as you suggest. Verifiability and Neutral point of view are polices not an optional features that you include in the articles or not based on whatever you think that either "everyone" or "99 main stream media" share your point of view. I have absolutely no interest discussing what you think about SLS, what are your thoughts about BFR, Falcon Heavy, Falcon XX or SpaceX as a whole.SkywalkerPL (talk) 10:08, 25 September 2014 (UTC)
 * Oh, and just to be clear, cause it seems that we have a misunderstanding here - I'm not disputing criticism against SLS, especially if it's well sourced, I'm disputing the fact that it's extremely one-sided with no counterarguments even though they clearly do exist. And just to remind you Gopher, cause you clearly go way over the board: SkywalkerPL (talk) 10:20, 25 September 2014 (UTC)

I will just note that the above Talk page section has become such a mess, with a discussion of a VERY wide variety of topics well beyond the quite narrow topic of the BRD on a few lines of article prose, and with (apparently) a lot of history and previous unsettled arguments brought into the mix, that for me, it's not really possible to continue having a rational discussion on the much more narrow topic that was originally under discussion in this section. YMMV, but if I have more to say, I'll likely say it somewhere where the topic breadth can be clearly limited to a single item at a time, and hopefully avoid the discussion being joined by a lot of history of previous (unfinished?) discussions that are unrelated. Cheers to all of you, N2e (talk) 11:36, 25 September 2014 (UTC)
 * So far the first person I seen making a posts that don't address anything at all on topic of the discussion is You, N2e, so I find your post very ironic overall, however I do agree that both topics of the discoussion: Competition for an American heavy-lift launch vehicle section and lack of counterarguments in Criticism section went the point where nothing more can be agreed through continued discussion. I'm out from here too. SkywalkerPL (talk) 11:57, 25 September 2014 (UTC)

Block IB lift capability to LEO
We have some pretty wild claims being made about the payload lift capability of the Block IB with the Exploration Upper stage. I believe the discrepancy between 93.1 & 118 tons to LEO is due to the sources that cite the first reference referring to actual payload and the latter to sources including payload+the fuel and engine weight of the Exploration Upper stage. Naturally seen as 93.1 is the payload to LEO capability; this is the more accurate figure.

In any case, we need to clear up exactly what payload capacity to LEO the Block IB SLS will have - [which is presently a vehicle architecture with the Exploration Upper Stage 2nd stage combined with the core stage's four RS-25 engines and dual 5(or 5.5) grain segment shuttle derived SRB's] - will really be capable of.

Thoughts? 178.167.254.30 (talk) 14:14, 21 August 2014 (UTC)
 * My understanding is that they're currently leaning strongly in favour of building the block 1 (70-some tonnes to LEO), waiting 20 years, and then maybe building block 2. Maybe. But probably not, since it's believed several more advanced, more capable, cheaper commercial alternatives will have long been in use by the time funding for the block 2 materializes. The block 1B had been deprecated (last I'd heard), and they have no plans of building it due to lack of funding. &mdash; Gopher65talk 14:43, 21 August 2014 (UTC)
 * Block IB is scheduled to fly as the second SLS mission, as reported extensively just a few months ago. The reason we don't have performance figures that agree is that the 93 ton capacity is from a study comparing several possible upper stages, none of which is exactly the EUS, which we don't know the actual performance of yet. The number will be clarified as the EUS design progresses (or is cancelled, who knows)  A ( Ch ) 17:28, 26 August 2014 (UTC)

"The SLS will launch the Orion Crew and Service Module and may support trips to the International Space Station if necessary. " Really? I haven't read any mention of plans to lift modules to ISS, although I suppose it's possible. Certainly it's many times too large for crew. Can someone cite justification for the second half of this sentence? Voronwae (talk) 03:16, 26 November 2014 (UTC)
 * Service Module is part of Orion stack and has nothing to do with ISS. Doyna Yar (talk) 04:28, 26 November 2014 (UTC)

Mishmash of units: 'metric ton' and 't', lbs and kg, etc
Really confusing having 'metric ton' and 't' used in the same article - would be better if one form were used consistently. As this is a US project, unfortunately it would seem that the SI 'tonne' may not be an acceptable form to use, however clear it might be. I would suggest that perhaps the first instance is written as xx metric tons (tonnes, t) so that more readers will grasp the units used, then subsequently use 't' for brevity. My feeling is that 't' is perhaps not a commonly known/used unit in Europe - I had to look it up (in Wikipedia of course). I wonder what NASA uses in its documents.

Also, have "...produce 1,800,000 lbf (8.0 MN) of thrust..." - imperial then metric. And "...propellant load of up to 285,000 lb (129,000 kg)..." - again imperial them metric. I'm sure it's best to be consistently and primarily metric throughout, and use imperial in parentheses for clarity for US readers. Taliska (talk) 02:43, 9 December 2014 (UTC)


 * US units are listed first for most measures since they are the primary unit and strong US ties. And yes, tonne is not the proper US term.  t is the official symbol on Wikipedia per WP:UNITS. Using '(tonne, t)' as you suggest should be fine.  Metric ton is the more common unit for payloads.  So that's listed first. -Fnlayson (talk) 03:05, 9 December 2014 (UTC)

Shuttle-derived?


To me it looks more like it was derived from the Saturn instead of the Shuttle. It looks a lot like a Saturn with two boosters strapped on. Bubba73 You talkin' to me? 04:27, 14 September 2014 (UTC)


 * Click on the Shuttle-derived link in the first sentence of this article and read that page. -Fnlayson (talk) 22:34, 14 September 2014 (UTC)


 * Unless the F-1 advanced liquid boosters get chosen there is probably no Saturn linage short of Michoud Assembly Facility and NASA logo. Doyna Yar (talk) 03:35, 15 September 2014 (UTC)


 * Take the side boosters off and it sure looks like something in the Saturn family. Bubba73 You talkin' to me? 01:32, 16 September 2014 (UTC)


 * Well reluctantly I'll give you that SLS form factor is very much constrained by the VAB from the Saturn program. I'm not sure where your line of logic is going with this in relation to the article? Doyna Yar (talk) 03:30, 16 September 2014 (UTC)


 * Not much really, except that Saturn V lists it as a proposed successor to the Saturn V, and it does resemble it quite a bit. Bubba73 You talkin' to me? 04:34, 16 September 2014 (UTC)
 * Whether or not the SLS is Shuttle-derived, is it accurate to say (in the first paragraph) that it's a replacement for the Shuttle? Wasn't the Shuttle limited to NEO? Misterjag (talk) 05:15, 17 December 2014 (UTC)

SkywalkerPL (talk) 09:01, 16 September 2014 (UTC)

EUS engines
Block IB's second stage, scheduled to debut on Exploration Mission 2 (EM-2), will use the 8.4 meter Exploration Upper Stage (EUS), previously named the Dual Use Upper Stage (DUUS), powered by four RL10 engines.

The conceptual design does use the RL10C-1 as a baseline, but the contracts for the EUS engines haven't been awarded yet, and NASA is still evaluating options. So, while it's certain they will have to be similar to the RL10, no engines have been selected as far as I know. -Daydreamers (talk) 15:49, 29 December 2014 (UTC)

Add 'expendable' in the opening paragraph?
As reference [24] indicates that nothing from the proposed vehicle is recovered during the launch, perhaps it is appropriate to add the term 'expendable' in the opening paragraph, and remove any reference about reusability in the article. 217.239.14.72 (talk) 00:21, 28 November 2014 (UTC)
 * Took me a while reading the article to figure out that there's nothing reusable in the design. For all the hype, isn't this much the same as good old Saturn V and that article uses "expendable" in the lead. — Preceding unsigned comment added by 217.207.145.188 (talk) 13:05, 30 December 2014 (UTC)

An off-topic arguments on content in Criticism section
My least favorite part of the criticism section is the propellant depot idea. First of all, any propellant depot in low Earth orbit would experience orbital decay and eventually fall back to Earth. Second, with the announcement of EmDrive it appears that spacecraft propulsion may not need any propellant at all once the spacecraft arrives at low Earth orbit assuming it has sufficient solar power. Brian Everlasting (talk) 02:18, 6 August 2014 (UTC)


 * *sighs* . Ok, so once again, EmDrive isn't real.


 * 1) The NASA team had a better test setup than the Chinese team, and saw 1000 times less thrust for the same power input. When better experimental setups eliminate most of the effect in question, that's usually an early sign of a death kneel. It indicates that the initial tests were shoddy, and that they weren't properly controlling for all the variables. This means that you can take the Chinese results and chuck them in the garbage, because they did a terrible job of testing their unit.


 * 2) The "researchers" (if you want to call lazy bums like that researchers) that NASA had testing the EmDrive didn't bother to test it in a vacuum. Why? Sheer and utter laziness. They mentioned in their paper that they should have, they just couldn't be bothered to do it. Why? They'd have had to replace a few capacitors before the test. So what did they do? Why, they tested it in a vacuum chamber, but didn't turn the chamber on of course. That's what any of us would have done, right? FFS. (I would have fired them all for this. And blacklisted them for their shoddy work.)


 * 3) About the one thing the NASA "researchers" did correctly (were they first year undergrads there on an internship? Cause that would explain it) was to build two test articles. One of them was designed to work, while the other one was a dummy unit. When they put power into them both units saw thrust. That shouldn't have happened if the microwaves were what was causing the anomalous thrust that was seen. This likely indicates that unaccounted for atmospheric effects were the dominant cause of the thrust that was seen.


 * They saw a very, very tiny effect. One that could easily be explained by the fact that they were too damned lazy to turn on the vacuum chamber. This is because the container holding the microwaves is asymmetrically heated by the microwaves. The hotter side of the container experiences some abnormal air currents, which then push the container away, generating "thrust". It's essentially a simple version of a Crookes radiometer.


 * So until they've until they've tested it in a vacuum chamber, EmDrive isn't a thing. Preferably tested it with a team of different people that isn't comprised of Beavis and Butt-head. If, after that is done, they still see an unexplained thrust, *then* we can all start to get excited. But not yet:P.


 * If you can't tell, I'm extremely disappointed in the poor quality of research done by this bottom of the barrel NASA team. And I'm not the only one. &mdash; Gopher65talk 03:29, 6 August 2014 (UTC)


 * Propellant depots - Propellant depots are a well-examined idea, and one advantage is that containers can be standardized and RFPs put out for delivery prices to a certain location. Orbital decay is not an issue; you launch propellant to where you need it and you can use cryogenic venting for long-term station-keeping.  They're just gas stations, which have worked well for the world.  They are absolutely a viable and extremely cost-effective alternative to a heavy lift vehicle.


 * EMDrive - Currently has no place in this article, but frankly the Eagleworks article withstood a long period of peer review before being published. Impulse response was immediate and coincided precisely with application of the on/off switch, and hence is unlikely to have been thermally-related.  You're mistaken about the nature of the Cannae control unit; it wasn't a dummy, it just didn't have the radial slits.  The data and the researchers have already withstood more-informed criticism, although as the researchers point out, it remains to be seen whether the drive will be determined to be real or revolutionary.  Your sighs are duly noted.  Voronwae (talk) 03:47, 26 November 2014 (UTC)


 * A basic depot is simply an upper stage vehicle with transfer couplers and a sunshield. It's got a largish motor or two, as well as RCS.  A depot has the capability to reboost and maneuver.  It can be refueled. While a depot might be retired and re-entered as a means of scrapping it when obsolete, atmospheric drag by itself is not a reason to allow decay and re-entry.  --Stevegt (talk) 20:44, 17 January 2015 (UTC)

Launch Manifest
Here is the SLS Block I Launch Manifest, published on 25 May 2015: ; Launch date is July 2018. It will fly 11 CubeSats as secondary payloads; some were selected already. Cheers, BatteryIncluded (talk) 19:18, 26 May 2015 (UTC)

SLS Block II will be the "most capable vehicle in history"?
There are a number of non-NASA sources stating the above, however during my two edits as the Irish IP user | 178.167.154.99 & this new IP number my service provided has just assigned to me, I have included two pieces of data on the Saturn V, one of which was made available by the stellar work of User:Alogrin over on the Talk:Saturn_V page, who has determined that the previously cited "118 metric ton" capability of the Saturn V was incorrect and based on shoddy references. It was in fact closer to 140 metric tons according to the references they uncovered. 92.251.136.96 (talk) 03:40, 18 August 2015 (UTC)


 * Regarding the new table, I am not familiar on the launchers' technical lingo, but is "payload mass" the same as "lift capacity"? I have a hard time believing they mean to place a 130 ton satellite (payload) in LEO. In aviation, the payload does not include the mass of the aircraft, just its useful cargo capacity. I am assuming a rocket's 'payload' is the equipment delivered to outer space, and it excludes the mass of the rocket fuel and the multiple stages and engines to get it there. My point is that if "payload" is not the same as "lift capacity", then it should not be used as a synonym. Cheers, BatteryIncluded (talk) 17:59, 7 September 2015 (UTC)

Errors in references
Hi, There are 2 errors in references right now: Regards, Yann (talk) 10:20, 18 October 2015 (UTC)
 * "Cite error: Invalid tag; name ":32" defined multiple times with different content"
 * "Cite error: Invalid tag; name "MarsRoadmap" defined multiple times with different content"

Proposed missions unexplained shuffle
Why are the Europa Multiple-Flyby Mission and Uranus orbiter and probe elevated to the top of this section when they belong in the 'Other proposed missions' section? And now the Tactical timeframe DRMs from the NASA roadmap are gone too? Why are 1) 'BEO Uncrewed Lunar Fly-by – Exploration Mission 1 (EM-1), and 2)BEO Crewed Lunar Orbit – Exploration Mission 2 (EM-2) deleted from the article? Doyna Yar (talk) 23:40, 1 November 2015 (UTC)

$5 Billion Launch Cost?
How can this possibly be accurate? NASA's Fiscal Year 2014 Budget request for Exploration Systems Development was $2.7 Billion. This included development of SLS, Orion and the ground systems. I would expect costs to go down after the first flight... not up. — Preceding unsigned comment added by 73.239.76.102 (talk) 08:28, 11 December 2015 (UTC)
 * It's not hard to validate or invalidate that number. We can do what's called a "first order approximation" to test whether that number is in the right ballpark. We can guesstimate the likely range of total costs per launch (including amortized development and program upkeep costs) with just a few bits of information:


 * 1) Actual costs per flight are expected to range between 500 million (which is almost certainly overly optimistic) and 1.5 billion. Let's use the simple average of that and assume 1 billion per flight. Might be a bit more, might be a bit less, but that's close enough for a first order estimate.


 * 2a) We don't know how many flights the SLS will eventually have, but we can guess based on current market developments and the political tailwinds the project has. The project has 4 "firm" flights. We'll assume all of those will go ahead. It's also likely that the SLS will be replaced with a much cheaper commercial launcher from one of several companies (Blue Origin, SpaceX, ULA) before 2035. All of those companies have expressed interest in replacing the SLS, and SpaceX has stated that they're in active development of a cheaper SLS replacement, which they expect to be testing about the time the SLS Block 1B first launches (~2021). Let's take that with a grain of salt though, and assume that SpaceX or another company will take longer than that to bring their SLS replacement online.


 * 2b) NASA has stated that they don't have the funds to launch SLS more than once every 1.5 years, at most. They also don't have the funds to develop payloads or Orion missions to launch even every 1.5 years. Without a massive boost to their budget (~3 to 5 billion per year would be nice), we can expect SLS to launch at most once every 2 years.


 * 2c) Taking those two things together, we know that there will be 4 launches (scheduled) of the SLS before 2027, and ~0.5 launches per year after that for ~10 years. So there will be a maximum of 9 SLS launches, barring a colossal shift of priorities in the US House and Senate (which while unlikely is possible, but we can't predict things like that).


 * 3) SLS development costs + Orion are now estimated at ~45 billion dollars, including the first 4 flights (it was 41 billion, but the Senate and House mandated to NASA that the SLS budget would be increased at the expense of other programs). This does not include the ~10 billion spent on the constellation program before it was cancelled, even though that technology was rolled into SLS. Really it's about a 50 billion dollar program in terms of development, plus ~ 1 billion for each and every flight. But let's ignore that extra 10 billion, because for some reason everyone else does.


 * 4) If there is a shift in Washington that leads to more SLS flights than currently estimated, total costs per flight (direct costs + amortized development costs) will of course go down. If SpaceX or ULA or BO manage to bring an SLS killer online by 2021 as they believe they could, SLS might not even get its currently scheduled 4 flights. If that happened, the costs per flight would of course go up. For step 5 let's assume neither of those happens.


 * 5) If we take NASA's estimate of 45 billion cost of development (including the first four flights) as gospel, then we add in the averaged estimate per flight of 1 billion for the estimated remaining 5 flights (for a total of nine), we end up with 50 billion in total program costs. 50/9 = ~5.5 billion per flight, amortized.


 * 6) If we're wrong and SLS gets 2 flights before being cancelled, total costs will be ~ 20 billion per flight. If it ends up getting 40 launches (no one - NO ONE - is projecting this) SLS will cost 45 + (40-4)*1 = 81 billion/40 = ~2 billion per flight.


 * 7) So now we have our range. At the far extremes of our estimate, the SLS will cost somewhere between 2 and 20 billion dollars per flight. The most reasonable estimate, backed by available data, is about ~5.5 billion per flight.


 * So yup, I'd say that 5 billion per flight is in the right ballpark. &mdash; Gopher65talk 18:48, 27 December 2015 (UTC)

Payload mass to various orbits chart
I think it would be helpful if the payload mass could be sort-able. Doyna Yar (talk) 16:48, 27 December 2015 (UTC)
 * Sounds good to me. Errr... I don't know how to do that though:). &mdash; Gopher65talk 19:03, 27 December 2015 (UTC)