Talk:Comparison of orbital launch systems/Archive 2

Ariane 5 ECA

 * I am still against putting a 20 ton to LEO performance against Ariane 5 ECA because :
 * 1) Ariane 5 ECA is unable to structurally handle such a payload.
 * 2) The cryo upper stage of the ECA is not reignitable (contrary to Ariane 5 ES), so the circularization of a 20 ton payload on LEO with a perigee raising maneuver is not feasible. Hektor (talk) 09:40, 16 May 2009 (UTC)

May I add that the 188 ton to LEO figure for Ares V is equally crazy. This is a figure based on a pure engine performance computation, but the primary structure of Ares V is not designed for a 188 ton payload. Ares V goal is to achieve 75 metric tons to TLI. How do I know ? I asked the question - is the 188 ton figure real - to Steve Cook himself (Manager, Ares Projects Office at Marshall) during the IAC Congress last year in Glasgow. Hektor (talk) 09:45, 16 May 2009 (UTC)

Deleted UR-900
I cut the UR-900 from the listing. This never made it past the conceptual design stage, and if the list is to include conceptual designs, there are a lot more that should be on the list, such as the Nova (rocket), the Sea Dragon (rocket), various shuttle-derived HLLVs such as Magnum, and many others. Geoffrey.landis (talk) 15:18, 17 May 2009 (UTC)

Year of first launch
Hello, Could you add a "Year of first launch" column please? It would be much more useful than the actual "Status" value. Yann (talk) 18:05, 1 June 2009 (UTC)
 * Sounds like a good idea, but I would suggest including a field for retirement dates as well. -- G W … 19:18, 1 June 2009 (UTC)

Possible source of missing info
Hi, I came across a possible source for more complete info on the Delta IV, Aries I, and Atlas V-Heavy (which is missing entirely from the article). This: http://www.floridatoday.com/assets/pdf/A912809629.PDF is an article from a local Florida newspaper in which they give a comparison of the targeted specs for the Aries I versus the existing Delta IV and the Atlas V-Heavy (which doesn't, technically, exist yet but is supposed to use 95% of the existing Atlas V's hardware and could be ready in 30 moneth according to it's producer). Specifically, the article gives values for overall cost per launch and cost per kg to LEO. I'm not sure about the validity of Florida Today as a source, but they claim that the numbers come from the Government Accountability Office's and NASA's 2008 fiscal year budget. This should help in making apples-to-apples comparisons between the various systems. I'd add the info myself, but I don't have an account and don't have the time to make one. I12.32.89.121 (talk) 21:13, 1 September 2009 (UTC)
 * The Atlas V Heavy is missing because this list does not deal with cancelled programmes. -- G W … 21:42, 1 September 2009 (UTC)

Delta IV Heavy WRONG NUMBERS
The heavy configuration of Delta IV by the article's own numbers indicate its record of 2 out of 3. The other launches of the Delta IV were of the medium variety, and shouldn't be included in the "heavy" 20KG+ range. The table suggests 9 out of 10 for the heavy configuration of Delta IV which is incorrect. —Preceding unsigned comment added by 74.178.55.76 (talk) 22:39, 8 October 2009 (UTC)

Yes, the above comment is correct. The value showing now of 9/10 probably was intended to show all Delta IV launches, but this is the "heavy lift" page, so only Delta IV Heavy should be included. While the Delta IV Heavy uses the same Common Booster Core as the non-Heavy Delta IV series, for the purposes of this "Heavy" page it should be treated as a separate vehicle. This is consistent with the main article for Delta IV.

I am changing the table to show 2/3 for launch record.

If there is disagreement, let's discuss it here before changing it back. Rebbargynnep (talk) 20:05, 18 October 2009 (UTC)
 * Actually, the numbers for the masses to GTO and LEO seem to be for the H+, which, as far as I can tell, has never flown...CyrilleDunant (talk) 16:41, 20 October 2009 (UTC)

Rus-M
The manned version of Rus-M can carry only 18.8t (this will be the rocket's primary purpose.) Should we point this out in the table? Offliner (talk) 07:44, 14 October 2009 (UTC)

Ares V - 188mt source?
Is it sure that Ares V has 188mt capability? In the 2009 Augustine report it is clearly reported as 160mt and maybe the 188 number is a confusion from the Constellation missions where Ares V (160mt) and Ares I (25mt) would launch two pieces that dock in LEO for a total of ~185mt? Alinor (talk) 13:08, 24 October 2009 (UTC)

Angara 7V
The Angara page mentions that Angara 7V has a maximum LEO payload capacity of 40,500 kg, this page talks about 36,000 kg. Which one is correct? 77.118.125.40 (talk) 08:44, 1 November 2009 (UTC)

H-IIB
Generally, various lanch capacities are found by citation. Yomiuri Shimbun(February 23, 2007) reported that H-IIB had about 20t / LEO 300km, which was quoted from JAXA's documentation. Clip of the newspaper's table was found in a rocket engineer's private website (in Japanese). I will not actively add H-IIB to this catalogue article, but need not to remove the existing description. --Gwano (talk) 09:30, 6 November 2009 (UTC)

Ares I - test launch
I don't think that we should add the Ares I test launch in the table - the launch was not of the Ares I rocket, but a development/qualification test - there was no second stage (used dummy) and the first stage was not Ares I first stage (5 segment SRB), but 4 segment SRB with dummy 5th segment. So this launch was a step in the development process and not one of the final steps (like test launches of other rockets), but an early step. Alinor (talk) 10:05, 28 January 2010 (UTC)
 * I'll have to agree here-- the Ares I-X launch was not the Ares I, although it was the same size and shape. If the "record" section of the article doesn't include non-orbital test launches of other launchers, it shouldn't include Ares-1.  Geoffrey.landis (talk) 16:21, 19 February 2010 (UTC)

Falcon 9 Heavy
The LEO capacity of Falcon 9 Heavy was 29610 until someone changed it to 32000 (both using the same source). The source itself seems contradictory (having two figures: 32000 and over-28000) - eighter "over 28000" is "32000" (possible, but not very likely) or both figures mean different things (like actual payload vs. payload+second stage transfer fuel vs. payload+fuel+full second stage mass - or similar distinctions). Alinor (talk) 12:19, 6 March 2010 (UTC)

Proton
Should the Proton be separated into Proton-D, Proton-K, and Proton-M? Or are these adequately similar so as to be considered as variants of the same launch system? i.e, tank size very nearly the same, fuels the same, engines basically the same. --Aflafla1 (talk) 04:20, 22 May 2010 (UTC)

actually achieved "mass to orbit"
This List compares Launch Vehicles by their Lifting capability's, it uses manufacturer supplied maximum theoretical values.

I would suggest a column displaying the greatest actually achieved "mass to orbit".

Since that should be the most meaningful Value in this comparison.

There are Vehicles that will never achieve their maximum theoretical values.

I don't know how difficult it would be to gather this data, since there are a number of military launches that may not publish much data? —Preceding unsigned comment added by Xylf (talk • contribs) 09:50, 24 May 2010 (UTC)

Atlas V HLV
From the Atlas V article it is not clear if the 30 month period for the HLV version includes development and first item manufacturing, or the development is already made and this is only the manufacturing time. (the other statements on the page were in the sense that HLV will not be developed at all). Alinor (talk) 14:34, 19 September 2010 (UTC)

Citation needed flags for launch numbers/etc
N2e, you have added such flags to many entries in the tables (not only here, but in the other launch vehicle lists too) and even removed some numbers that were without citation. For example recently you added "citation needed" on Long March 2A launch record, but after opening its article I found the information and also this link where it was present too. So, while I could understand adding "citation needed" flags to any data without citation - I think it is better to first look if it is not present in the relevant launcher article (sometimes these articles contain list of launch attempts and you have to count the appearance of the particular launcher there).

In any case removing data (especially if present in the relevant article) is too much. If you don't want to look in the articles/count from the lists/copy the references - please, put a citation-needed flag, but please don't delete the content (as the Titan records here).

The case is similar with Operational vs. Retired status - there are few "official announcements" of retirement, especially for the older rockets (that are much more unlikely to be still operational/available), so while it could be dubious that some rocket is still operational/already retired (Sputnik?, Ariane 5GS?) and so a "citation needed" flag is required - deleting the status will be an overreaction. The problem that I see with so many citation needed flags is that the whole column could get deleted "after xxx time passed" and that would not do any good. Alinor (talk) 09:38, 21 September 2010 (UTC)


 * Basically, anyone removing uncited data is always doing the right thing. It should have been up to the person who inserted the data to provide inline cites. But I agree that it would be fair if N2e looked at the launcher articles first before removing the data. Offliner (talk) 15:02, 21 September 2010 (UTC)


 * Thanks for the comments Alinor and Offliner. I think we are all working for a better and more encylopedic Wikipedia.


 * First off, I try very hard to not remove any numerical claims that have not been previously tagged by citation needed tags, and then generally only after the tags have remained with no source provided for at least six weeks. If you are aware of anywhere where a (non-obviously incorrect) claim was removed by me where I did not follow that process, I would very much appreciate your bringing that instance to my attention.


 * Secondly, I often am familiar with other relevant articles, as Alinor suggests and Offliner supports. However, Wikipedia policy does call for any substantive claim in all articles to be verifiably sourced per WP:V, a core wiki-policy. Wikipedia itself is not considered an adequate source:  see the section Wikipedia and sources that mirror or use it in the WP:V policy.  The lone exception, where sources are not required, is disambiguation pages.  We need not cite every detail about any particular rocket, but if a claim is made about the size, capacity, successes/failures, etc., (all of which are assertions), then a citation should be provided that will source those claims about that rocket.  The very acceptable alternative is to make fewer claims in these "List of..." or "Comparison of..." articles and leave the detail to be claimed, and then only sourced, in the article that covers the individual rocket.  N2e (talk) 17:25, 21 September 2010 (UTC)


 * OK, I understand that you follow 'citation needed' rules. But I don't think it is beneficial to remove any uncited numbers after 6 weeks. For example Saturn IB was recently tagged, but its article contains the list of launches and this source. It is highly possible that the 6 weeks will pass without anybody checking/copy-from the launcher article. What will happen in this situation? Alinor (talk) 15:21, 22 September 2010 (UTC)


 * I don't do what I do on unsourced claims to "follow 'citation needed' rules." I do it to help make Wikipedia a better and more robust encyclopedia in the long term.  Over the long term, all the unsourced claims are subject to being removed from the encyclopedia by myriad other editors in much less than six weeks, which would make an article that might have a lot of "good stuff" in it, however one measures "good stuff", lose a lot of info.  I thus add citation needed tags to some parts of the article, working at the margins as it were, to get the unsourced stuff gradually removed, or sourced, both of which make Wikipedia a better encyclopedia.  Following through after some time has passed to delete unsourced claims is just a necessary part of the process.  In many articles, the editor who orginally made the claim, or other editors who care, source the claim and it comes back.  This is consistent with WP:BURDEN, a part of WP core WP:V policy.  Cheers.  N2e (talk) 21:00, 22 September 2010 (UTC)
 * The problem I described is that sometimes the content is sourced, but there is no [1] link right after it, so you have to click on the launcher article (and maybe its history of edits comments) to find the source. It is reasonable to expect that many of the numbers in the tables would not have "their own" sources, but would came from the launcher article. So, in the end sourced information can get deleted (in the examples I gave above - and maybe others). Alinor (talk) 08:54, 23 September 2010 (UTC)
 * For example - 2 days have passed since I had given the first example of the sourced information that has a 'citation needed' flag regardless (Long March) - and nobody copied the link/removed the 'cn' ... in 6 weeks this sourced information could get deleted. Alinor (talk) 08:57, 23 September 2010 (UTC)


 * So I think the solution is for the editor or contributor who wants the information to remain in Wikipedia, to add it back in with a source, per WP:BURDEN, which is included in Wikipedia core policy WP:V. In my view, for the making of a good encyclopedia, it doesn't really matter whether that happens before or after the uncited claims are deleted.  Either way, the information is not lost; it would merely be "temporarily" missing until such time as an editor adds it back with a citation. If it is true, it should be easy to supply a reference. If it is not true, it should be removed.N2e (talk) 14:08, 26 September 2010 (UTC)


 * "'I really want to encourage a much stronger culture which says: it is better to have no information, than to have information like this, with no sources. Any editor who removes such things, and refuses to allow it back without an actual and appropriate source, should be the recipient of a barnstar.' —Jimbo Wales, July 19, 2006"
 * So, you insist on putting citation flags everywhere and then deleting everything? Why don't you agree to simply check in advance for sources in the respective launcher article - so that no tags are added to already sourced material? I gave you such example above. Alinor (talk) 16:27, 7 October 2010 (UTC)
 * Otherwise it seems like "I will put flags on everything without checking if this is needed. I leave for all the rest to scramble to check and copy-paste the sources. If they don't I will continue by deleting everything." Alinor (talk) 16:30, 7 October 2010 (UTC)

N2e, I see that the sourced data in the Long March 2A entry (where you added a 'citation needed' tag without checking the launcher article - see 09:38, 21 September 2010 comment above) is deleted. I see that the 'citation needed' tag on the Saturn IB sourced information (see 15:21, 22 September 2010 comment above) still remains. I see that you continue to add these tags and delete data. I assume that there are other cases (than the two examples I mention above) where you does this on sourced information. Do you agree that you should first check for sources in the launcher articles before adding these tags or you continue to insist on deleting all information from these lists here by playing the 'add citation tag without checking - wait - delete' game? Alinor (talk) 15:13, 27 December 2010 (UTC)


 * Alinor, this has been discussed a couple of times above, I thought rather fully. But since you asked again, I will attempt to clarify it more fully in the following section.  N2e (talk) 16:16, 27 December 2010 (UTC)

On sources and citations, and cleanup of the same

 * Adding sources to articles, and requesting that an unsourced claim be cited, are orthogonal endeavors for Wikipedia editors. I support BOTH adding sources AND adding verifiability-related citation tags to articles that need improvement.  I frequently add citations to articles I work on, and also on those I stumble upon that are in my area of interest or expertise.  These actions however are orthogonal to other actions that I also choose to take to tag unreferenced material.  WP:Verifiability is not optional.  Policy is unambiguous, it is up to the editor who wants to retain material in Wikipedia to get it cited with verifiable sources; it is NOT WP policy that every editor who stumbles upon significant unreferenced material must stop their lives and endeavor to improve THAT particular article, nor ignore that the article or claim that has no sources.  So in many cases, I simple note it with a polite (and smalltext) tag and move on.  It seems to me to be a simple courtesy to flag it for a month or two to see if "the community" cares enough about an article to fix it before material is (temporarily?) removed from Wikipedia for being unsourced. Cheers. N2e (talk) 16:16, 27 December 2010 (UTC)
 * I have provided you above the following two examples what your process of 'tag everything-wait-delete' accomplishes:
 * Sourced material tagged. Currently in "wait" phase. To be deleted? see 15:21, 22 September 2010 comment above
 * Sourced material already deleted. see 09:38, 21 September 2010 comment above
 * these two are just examples - I assume that the situation is similar with most of the information here that you tagged-waited-deleted.
 * The process you want to employ here may be appropriate for a regular text article. But these here are summary tables - mostly displaying information that is already sourced in the individual launcher articles. If you continue your process without taking into account the sources in the individual launcher articles (or another related Wikipedia article such as "List of Shuttle flights" linked from the individual launcher article - in cases where it's too big) - eventually the tables will become stripped out of their data and thus useless. Do you want to delete these articles?
 * I assume that you genuinely want to improve the articles, but I gave you the above examples ~3 months ago and now I see that you haven't corrected those two mistakes. So, it seems you don't care to improve, but just to delete. Alinor (talk) 07:04, 28 December 2010 (UTC)
 * As I said above - it's one thing to put 'citation needed' flag everywhere - it's different to actually delete the data. Alinor (talk) 07:09, 28 December 2010 (UTC)


 * Alinor. Let me address your wide-ranging response with three important ideas.  Please read them carefully, as I feel like we have discussed the first two items, rather thoroughly, previously:
 * On the contrary to your statement: "Sourced material already deleted.", I have not deleted sourced material, at least not intentionally, and should I ever do that, it would be a one-off mistake and the material should be restored, of course with the source alongside as a citation once again, just as you are implying when you say the material was sourced. But I think you will find that any material deleted was, in fact, unsourced.  Wikipedia requires the material be cited in the article that the claim is made in; otherwise it is not sourced.  Two ways to fix this:  1) just link to the other article and refrain from making additional unsourced claims about various details of an item in a "list of ..." article when an item has an article of its own, with fuller details; or 2) provide a valid citation per WP:CS and WP:BURDEN.
 * It is not okay to use Wikipedia itself as a source; see WP:CIRCULAR. Wikipedia standards for verifiability and reliable sources apply to all articles except disambig articles; list articles are no exception.
 * You say about me: "it seems you don't care to improve, but just to delete." Careful here.  You are skating on thin ice.  I suggest that you kindly keep the discussion, per Wikipedia community standards once again, to commenting on content, not on the contributor.  Cheers.  N2e (talk) 14:11, 28 December 2010 (UTC)
 * Why do you refer to WP:CIRCULAR? In the comments I refer to I speak about external sources (and even gave you the links - taken from the individual launcher articles), not about Wikipedia articles. Alinor (talk) 15:41, 28 December 2010 (UTC)
 * The source citation needs to be in THIS article, the article that makes the claim. Not some other article on Wikipedia.N2e (talk) 16:52, 28 December 2010 (UTC)
 * Irrelevant. WP:CIRCULAR is prohibiting the use Wikipedia content itself as source, not the use of external sources from another article. If the individual launcher article DOESN'T have external sources - then you can claim WP:CIRCULAR is breached. The examples I gave you are the opposite. So, you either didn't read WP:CIRCULAR or you didn't read my comments. Alinor (talk) 06:52, 29 December 2010 (UTC)
 * WP:NPA. I keep the discussion, in this case, to the editing process you employ. Alinor (talk) 15:41, 28 December 2010 (UTC)
 * Keep it to commenting on content, not on the contributor. Your comment crossed the line.N2e (talk) 16:52, 28 December 2010 (UTC)
 * My comment still stands (plus - see above point) and you haven't given reasonable explanation for your editing process. Alinor (talk) 06:52, 29 December 2010 (UTC)
 * Alinor, I have given an extraordinarily deep explanation of what I am doing and why I have done it. It really is quite beyond me why you aren't able to understand.  See above, in detail.  Having said that, I will offer no more explanation to you about how I choose to prioritize my volunteer time as a Wikipedia editor, as this is not to be determined by you or any other editor.  However, I will be happy to discuss article content.  Bottom line, if article content makes claims that are unsourced, I will from time to time challenge some content and ask for sources.  If no source is provided for the claim—in some reasonable period of time, typically six weeks or more—I may temporarily remove the assertion until an editor chooses to add it back in with a source.  N2e (talk) 05:46, 30 December 2010 (UTC)
 * Your fix suggestion "1) just link to the other article ..." - so, in the case of Long March 2A (see 09:38, 21 September 2010 comment above) there was a link to the launcher article, where the launch record is presented and sourced. Why did you delete it from the list article? And more importantly - after I have explained your mistake - why didn't you correct it (e.g. restore the numbers)? Alinor (talk) 15:41, 28 December 2010 (UTC)
 * Per WP:BURDEN it is not someone else's job to cite what you want retained in the article.N2e (talk) 16:52, 28 December 2010 (UTC)
 * Why do you suggest then as fix to "just link to the other article"? It is linked - in the first column of the table. Then, in the next columns the figures are taken from the article linked in the first column - and thus backed up by the sources from the article linked in the first column. That's the idea of these comparison articles - they are not the primary point-of-entry of the data - they just summarize what is entered in the individual launcher articles. In case of exceptions (e.g. data that is entered only in the comparison article) - then we need a source - but in most cases we don't - because it's already in the linked article. Otherwise we have to copy all sources from all individual launcher articles - unnecessary duplication and cluttering. And if your idea is to do this - do it, but don't expect that others should correct your mistakes and that others should police after you and look what sourced data you have deleted and restore it, etc. Alinor (talk) 06:52, 29 December 2010 (UTC)
 * The same goes for the Saturn IB launch record (see 15:21, 22 September 2010 comment above) - you tagged it, I explained you above that this is a mistake - why didn't you correct it (e.g. remove the tag)? Alinor (talk) 15:41, 28 December 2010 (UTC)
 * Per WP:BURDEN it is not someone else's job to cite what you want retained in the article. If you want it retained, add a source citation. N2e (talk) 16:52, 28 December 2010 (UTC)
 * OK, so I explained to you your mistake 3 months ago and you didn't care to correct it. You insist that somebody else corrects your wrongly put tags and deletions? Fine, then continue.
 * What's your goal? A] To have a sourced number for Saturn IB launches or B] To delete all data? If it's A] then I gave you the source taken from the individual launcher article - 3 months ago (when you didn't dispute the source or said anything - you just ignored it) you could have removed the tag (as it's unnecessary in this situation) or if you so insist - you could have added the source yourself. But you have done neither of those - so it seems you aim for B]. Alinor (talk) 06:52, 29 December 2010 (UTC)
 * When you add these tags do you even look at the linked launcher articles and their sources? Alinor (talk) 15:41, 28 December 2010 (UTC)
 * Sometimes I have done so. Sometimes not.  It doesn't matter as the claim that is made is THIS article needs a source.  It of course should be sourced in the other article as well.  But if the claim is to stand in THIS article, it needs a source in THIS article when challenged.  N2e (talk) 16:52, 28 December 2010 (UTC)
 * Yes, what you say is correct - if some data in the summary table article is reasonably challenged then it should be sourced. But this applies to exceptional cases where the summary article has some data that isn't present (and sourced) in the linked article (see Long March 2A reply above). There is no reason to challenge data that is already present in the linked articles if it's sourced there. That's why you should check there before adding tags. Alinor (talk) 06:52, 29 December 2010 (UTC)

N2e, as you said above that you don't want to discuss this editing process any further I asked for external opinions here. Alinor (talk) 09:48, 4 January 2011 (UTC)


 * I am happy to have others come in and offer opinions on the issue of citations. You may want to go further and make a formal Request for Comment.


 * But I do want to correct your paraphrase of what I have said. I have not said that I "don't want to discuss the editing process."  I have said that I will no longer discuss, with YOU, how I choose to prioritize my volunteer time as a Wikipedia editor.  I am quite happy to discuss article content, and whether articles ought to have reliable sources for the claims that are made.  I won't be discussing, with you, whether I ought to do the work, for free as a volunteer, of finding sources for every claim that does not have them that I have (politely) challenged and then allowed substantial time for them to be remedied by any editor who wants the claim to stand.  Here is my full quote, in context, that I last wrote on this Talk page a week and a half ago:


 * "'Alinor, I have given an extraordinarily deep explanation of what I am doing and why I have done it. It really is quite beyond me why you aren't able to understand. See above, in detail.  Having said that, I will offer no more explanation to you about how I choose to prioritize my volunteer time as a Wikipedia editor, as this is not to be determined by you or any other editor.  However, I will be happy to discuss article content.  Bottom line, if article content makes claims that are unsourced, I will from time to time challenge some content and ask for sources.  If no source is provided for the claim—in some reasonable period of time, typically six weeks or more—I may temporarily remove the assertion until an editor chooses to add it back in with a source. N2e (talk) 05:46, 30 December 2010 (UTC)'"


 * Others, please do weigh in on the subject of verfiability. Cheers.  N2e (talk) 04:31, 11 January 2011 (UTC)
 * 'I am quite happy to discuss article content' - you haven't restored the data pieces backed by external sources at the wikilinked articles that you tagged/deleted and I pointed out months ago.
 * About the editing process, that you don't want to discuss with me - from the discussion I announced above (this) it appears that your editing process is technically OK, because even WP:LISTS requires any challenged content to have external source in the same article - and external sources in wikilinked article are not taken into account. You didn't join the RS/Noticeboard discussion, but if you want you can join this. Alinor (talk) 12:02, 11 January 2011 (UTC)
 * Let's talk content. I think content in Wikipedia should be sourced, per policy.  Thus, I think that the claims that were removed (because they were unsourced) would make the encyclopedia better if they were present, with a source.  But absent a source, then Wikipedia is a better encyclopedia if the unsourced claims are (temporarily) removed.  That's the content discusion.
 * You seem to be talking process when you say "you haven't restored the data pieces backed by external sources at the wikilinked articles that you tagged/deleted". As to process, Wikipedia policy is also quite clear.  Any editor who adds or restores material has the burden to see that it is properly sourced.  I don't know, and I won't speculate, on the reasons that no editor who wants such claims restored, and believes the claims are reliably sourced elsewhere, has not restored them to this point in time.  I will say that I suspect the reasons are different for different edtitors.  N2e (talk) 06:35, 14 January 2011 (UTC)

I can't say I've read in detail all of the above discussion, but I generally agree with what N2e is saying. Namely that each article should contain it's own sources, and not rely on other articles' sources; that the burden is on the editor who wants to include material, not the editor who wants to remove it; and that the discussion should be about the article content, and not about a particular editor's editing style. Mlm42 (talk) 06:47, 14 January 2011 (UTC)
 * The most recent discussion is here. Alinor (talk) 12:02, 14 January 2011 (UTC)
 * N2e, from here: if you really want to improve the summarizing articles - would you agree to employ slightly different process: instead of "tag-wait-delete" use "tag-wait-check-delete"? (and if the "check" step reveals that the information is backed by external sources at the wikilinked article - then "copy" or "don't delete/continue wait")?
 * When I showed you the places where the claim is sourced you've just ignored these. That's part of the problem here. The other part is that it's pretty easy and straightforward to click on the wikilink and check for sources there. Even if current policy doesn't require that editors do this. Alinor (talk) 09:29, 15 January 2011 (UTC)

The following sections are being moved here, to Talk:Comparison of heavy lift launch systems, from User:N2e's talk page. The topic of the article and who should add the citations ought to be here, not on my Talk page. N2e (talk) 05:24, 16 January 2011 (UTC)

":::N2e, I don't agree with the allusion you make above 'improving the article, not about the editor.' - I have not discussed 'N2e, the person', but only 'N2e editing process' in the light of your tagging/deleting of data pieces that are backed by external sources (albeit not inline, but at wikilinked article). And that is the reason I continued to pursue this issue - you have not commented on these examples I gave, you have not corrected your wrong deletion/tagging (or objected that the examples I gave are incorrect) - for months! You don't even agree to first check for sources at the wikilinked articles before tagging/deleting. I can assume that a good-faith editor wants to improve verifiability, even going somewhat over-the-edge (IMHO) with generous tagging/deleting - but why doesn't he revert these when presented with examples that they are wrong?" ":::The combination of A] ignoring examples of your mistakes (by neither objecting nor correcting) and B] refusal to 'first check, then tag/delete' - this is what bothers me. Do you want these articles deprived of all information (and eventually deleted)? If so, please be frank and just file an AfD proposal." ":::If you really want to improve them - would you agree to employ slightly different process: instead of 'tag-wait-delete' use 'tag-wait-check-delete'? (and if the 'check' step reveals that the information is backed by external sources at the wikilinked article - then 'copy' or 'don't delete/continue wait') Alinor (talk) 09:38, 14 January 2011 (UTC)"

"::::N2e, When I showed you the places where the claim is sourced you've just ignored these. That's part of the problem here. The other part is that it's pretty easy and straightforward to click on the wikilink and check for sources there. Even if current policy doesn't require that editors do this. Why do you continue to object to check? Alinor (talk) 09:36, 15 January 2011 (UTC)"

Discussing my editing process is exactly what I told you, on the article Talk page, that I would no longer talk with you about, since you have ignored my previous extensive discussion of it with you (also, on that Talk page). Discussing article content is great, as I've said. The content will be whatever is left after either 1) appropriate sourcing BY THE EDITOR WHO WANTS THE MATERIAL RETAINED or 2) if it is removed until such time as a source is added. But that also should be done on the article Talk page. So I'll be moving this continuation of that discussion to that page shortly, and deleting it from my user talk page. N2e (talk) 05:18, 16 January 2011 (UTC)
 * N2e, I'm sorry you took this issue as personal. I think that I was civil and polite toward you and hasn't insulted you. Also, I refrained from filing AN/I without notifying you first about my intention to do so and I tried to find a compromise one more time. Also, I don't think that I have ignored any of your comments as you write above. On the contrary - you ignore the examples of sources I gave - despite your repetitive "content discussion is welcome". You ignored my examples of CONTENT tagged/deleted that has EXTERNAL SOURCES (you can see them at the wikilinked articles - I understand that policy allows you to tag/delete without checking there, OK. But, for the purpose of discussing this content you can open the wikilinked pages and see the sources, right? What is your opinion on that content? Will you discuss it?
 * Anyway, I don't have the time to go after all of your deletions/tags - these two I gone after were just that, examples. Since you refuse to even discuss "check before delete" I don't feel obliged to do this instead of you. You can continue your harmful practice until it's technically supported by Wikipedia policy. Alinor (talk) 11:36, 16 January 2011 (UTC)

the end of the matter (hopefully)
Alinor, a few final words on this, since you have continued, once again, making statements that reflect your heartfelt concern about what items I ought, in your opinion, to spend my editing time concerned about.


 * Contrary to your assertion, I did not take this as personal. I think you are an editor who works diligently to improve Wikipedia in your own way, and one who honestly wants all these claims to be left in the article.  Further, I believe you would really, strongly, and truly like me to do the work of finding citations for these unsourced claims, and then do more work to add them to the article.  However, as I have made clear to you previously, I don't want you, nor really any other editor on Wikipedia, suggesting what ought to be my priorities for use of my Wikipedia editing time.  Each of us has liberty in that area of our lives.  That is why I have said this to you at least twice now—a little more strongly the last time, on 05:18, 16 January 2011 (UTC) yesterday, when I moved your extensive recitation of previously discussed topics about this article off of my Talk page and to this article Talk page above:  I will not discuss my editing priorities, my editing process, with you any longer.  Our previous discussions, despite best efforts, seem to have borne little fruit.
 * Your efforts to get an interpretation of Wikipedia sourcing policy more friendly to your position, at (Reliable_sources/Noticeboard/Archive_87), failed.
 * Given that, your efforts to then get a change to the existing WP:V policy here seem also not to have borne any fruit for your position. Here is that link for other interested editors:  Sourcing for summarizing articles
 * Finally, you keep asking me why I have not gone and looked-for/checked-if-they-exist clear, cogent, complete and non-orginal-research citations in other articles and then ensured that, if found, ensured that they are added to this article. I have said all I'm going to say about that to you.  I'll give you no more answer than the many words above, and in this final summary, where I have tried to answer you about the matter.  In short, I'm not going to do the work for "the editor who wants to retain unsourced material in this article."  That work will simply need to be done by any editor who does want it retained.  You have said "I don't have the time to go after ..." finding sources for all the unsourced claims.  No problem.  And I would not ask you to do so.  Your editing time is yours; set whatever priorities you wish for it.  Please allow me to set my priorities for my volunteer editing time as well.

Those are the answers to your questions, to the best of my ability to answer them.

So here, once again, is a summary of my view on improving Wikipedia with respect to unsourced claims:
 * I see a citation needed tag in an article is a courtesy to those editors who care most about a particular article, or are perhaps are knowledgeable or expert about where the secondary literature might support the assertions being made. Unless someone who cares comes along to reliably support the unsourced claims with inline citations, they have no place in a quality encyclopedia.  Furthermore, per WP:BURDEN, it is the editor who wants the unsourced material to remain in an article that has the burden to cite it, or add it back to the article later once a source has been found.
 * In my view, Wikipedia is improved in one of two ways then:
 * either an unsourced assertion gets a citation by some editor who wants it retained, or
 * the unsourced material is later (politely, and only after a long period of time in which interested editors might have sourced it if they so chose) temporarily removed from Wikipedia until such time as someone does actually do the work to source it.

And as Forrest Gump said, that is all I have to say about that.

I hope we can continue to work on improving the encyclopedia on articles where we work together from time to time. But as for sourcing policy, and for who should do the work of finding and adding citations for unsourced claims added by other editors who apparently did not care enough to source their claims when initially added, I think it is fair to say that you and I ought to just agree to disagree, and move on. Good luck, and best wishes for your continued work with Wikipedia. N2e (talk) 01:23, 17 January 2011 (UTC)
 * OK, thanks. I still don't see what's your opinion about the examples/sources I have given months ago, whether they should be copied or not. Anyway, I'm repeating myself - it seems we both have nothing more to say here. Alinor (talk) 09:26, 17 January 2011 (UTC)


 * Thank you for your gracious comment, and willingness to let it go. The answer to your last question is that either an unsourced assertion gets a citation by some editor who wants the claim retained or the unsourced material will eventually be (temporarily?) removed from Wikipedia until such time as someone does actually do the work to source it.  Best wishes.  N2e (talk) 14:30, 17 January 2011 (UTC)

Saturn V
Wouldn't readers expect to find the Saturn V in the table of heavy lift launch systems as a retired launcher?Zebulin (talk) 20:04, 8 July 2011 (UTC)
 * Its a super-heavy lift, by a long way. WatcherZero (talk) 20:11, 8 July 2011 (UTC)
 * why do we need a separate super heavy lift article?Zebulin (talk) 14:06, 11 July 2011 (UTC)
 * Fundamentally they are launchers capable of sending a manned craft to the moon. WatcherZero (talk) 14:34, 11 July 2011 (UTC)
 * Zebulin asks a valid question. The lists are short enough that they shouldn't need to be split. Far smaller rockets could be used to launch manned Lunar missions with smaller spacecraft and/or different flight profiles. I would support merging all of the Comparison of...launch systems articles into a single list, entitled Comparison of orbital launch systems. -- G W … 15:36, 11 July 2011 (UTC)
 * I wouldnt mind a page with the four tables, just explaining why the super heavy were seperate from heavy which was the question. Also to note some of the small launchers are suborbital so would have to be removed from list if you named page as such. WatcherZero (talk) 16:47, 11 July 2011 (UTC)
 * They shouldn't be. Only orbital launch systems should be included, although if I recall correctly the "small" table does include suborbital launches of orbital launch systems in its success rates column. This is one of many minute formatting differences between the various tables, which would be standardised if they were merged. -- G W … 12:50, 12 July 2011 (UTC)

Space Shuttle Launches
There have been 135 space launches (according to the List of space shuttle missions article), not 132. There have been 1 launch failure (STS-51-L). STS-107 failed to land, but the launch and satellite insertion into orbit was successful.

Should the numbers be 134/135. Why the difference in the number for this article? user:mnw2000 18:04, 9 July 2011 (UTC)
 * The figure is out of date, and the outcome of STS-107 is being discussed above. -- G W … 15:37, 11 July 2011 (UTC)
 * Using article from NASA, the final official number is 133/135 with two missions not "complete". user:mnw2000 10:33, 21 July 2011 (UTC)
 * No one is questioning the number of successful missions. The question is the number of successful launches, but an impasse has been reached because the definition of a successful launch is being disputed.  Jparenti (talk) 05:48, 22 July 2011 (UTC)

Launch History
The number of launch failures for the space shuttle should be listed as one, as of today's date. STS-51L is the only mission to sustain a launch failure, as Columbia's last mission, STS-107, was a failure at reentry, not at launch. Since the table explicitly says "launch history" and not "total mission success", it should be left as it is. The fact that the shuttle orbiter is reusable does not mean it should be held to a different standard when calculating launch failures. That could be considered original research, or even opinion, since the definition of a rocket launch has not changed since the space age began. If you disagree with this assessment, please state your case before editing. Jparenti (talk) 09:05, 7 July 2011 (UTC)
 * No, STS-107 may have disintegrated during reentry, but it did so because of damage sustained during launch. Since returning to Earth was a primary mission objective, and damage sustained during launch prevented this from happening, it is correctly classed as a launch failure. You have violated WP:BRD by restoring your preferred version without discussing the issue, so I have reverted back to the original version, which per policy should remain in place until a consensus forms to change it. -- G W … 15:48, 7 July 2011 (UTC)
 * Hmm. Actually, I was being "bold" by changing it to the correct number.  WP:BB  Then, I posted here to inform anyone of the change and why it was made.  A launch is defined as a vehicle leaving the ground and reaching space successfully.  That is what STS-107 did.  You are making up your own definition, and since the chart does not say "overall mission success", then you are relying on your opinion.  It's not original research to see that the vehicle reached space successfully, meaning that the launch was indeed successful.  Read note 2:  "The column launch record is defined here as the number of times the launch vehicle achieved a desired orbit (e.g. payload separation orbit, final mission orbit, etc.) with the payload intact, divided by the total number of attempted launches.  Launches into a useless orbit (i.e., an orbit from which the payload is unable to operate) are excluded from success, as is the case of a launch in which the payload was destroyed before the launch vehicle achieved a desired orbit. Success of the launches is determined by the performance of the launch vehicle itself and classification is not affected by subsequent failures of other elements like payload separation failure, payload propulsion failure (not reaching a desired payload final orbit from the desired transfer orbit), other payload failures (including re-entry failures). Other definitions of launch success may result in different values for the launch success record (see notes where applicable)."  Seems pretty clear to me.  Jparenti (talk) 11:08, 8 July 2011 (UTC)
 * Do sources call the launch a success or a failure? We have to be careful that calling the launch a failure is not original research. Mlm42 (talk) 22:01, 7 July 2011 (UTC)
 * http://spaceflightnow.com/shuttle/sts107/030116launch/ Looks like it was a success.  And note 2 specifically says that re-entry failures are not counted as launch failures.  69.160.179.244 (talk) 11:41, 8 July 2011 (UTC)
 * Apologies for the previous post -- my browser logged me off, so the above comment is mine. Jparenti (talk) 11:43, 8 July 2011 (UTC)
 * Since that source was published on 16 January 2003, two weeks before the full extent of the failure became apparent, I don't think it can be given any weight whatsoever. -- G W … 21:06, 10 July 2011 (UTC)
 * Please read what I wrote in my previous comment. Re-entry failures are not considered when defining a successful launch. Therefore, the article I provided is relevant, and STS-107 was a successful launch.  You are using a definition of success that exists in your own mind, not in any of the sources provided.  Jparenti (talk) 18:33, 11 July 2011 (UTC)
 * Well, unless there's a source that says otherwise, then it looks like the launch was a success to me. Mlm42 (talk) 16:33, 11 July 2011 (UTC)
 * This explicitly states that the launch was a failure for the reasons I have outlined above. This describes it as a "catastrophic failure due to a breach that occurred during launch". I am yet to see a source published after the establishment of the cause of the failure which describes the launch as successful. -- G W … 20:50, 11 July 2011 (UTC)
 * Then Note 2 needs to be changed. It quite explicitly says that reentry failures shouldn't be considered when determining if a launch is successful.  Why should this apply to every launch except shuttle launches?  I have no idea how it can be said that the launch was unsuccessful if the payload was placed in its intended orbit, which is the definition of a launch according to what is already in the article.  There's no original ideas here -- I'm just reading what's already been written and approved.  Jparenti (talk) 06:28, 13 July 2011 (UTC)
 * The note could be changed to say "as is the case of a launch in which the payload was destroyed before the launch vehicle achieved a desired orbit, or the payload was damaged during launch such that it could not complete its mission". Defining success will, however, always be open to interpretation, so I would suggest removing the count of successful launches entirely, and going solely with the number of flights. This would also resolve disputes about the number of Saturn V and Energia failures in the Super Heavy table, and probably a few others too. -- G W … 16:38, 13 July 2011 (UTC)
 * I thought about suggesting the removal of the launch success category, but I felt uneasy about reducing the informational content of the article. As defined in the article at the current time, STS-107 would be listed as a launch success, simply because the standard used to count all the other launch systems' successes and failures is that the vehicle only needs to achieve its intended orbit to be considered successful.  If the category was "mission success", I would absolutely agree that the shuttle program has had two failures.  But as it is currently written, the column should list one failure only.  Two suggestions from me:  Remove the "successful launch" counts entirely from the article, or change the name of the column to "mission success".  I am afraid that both of those changes would invite more problems, and neither one seems like the best solution, but I don't see another way to resolve this without any more contributions or suggestions from other editors.  Jparenti (talk) 05:00, 14 July 2011 (UTC)
 * &bull; Perhaps it will be better to have 3 columns, with "launches", "mission success", "landings". Or in one column "Launches/Mission Success" --FlyAkwa (talk) 17:16, 26 July 2011 (UTC)
 * It makes little sense to do that when only one launch system would be affected. Unless you are proposing to count all spacecraft failures against the reliability of the launch system? The issue at hand here is the fact that STS-107 failed to land as a result of damage sustained during launch. I have no problem with listing something such as the Mars Climate Orbiter as a successful launch since its failure was not affected by its launch. -- G W … 17:42, 26 July 2011 (UTC)
 * I was thinking also about Saturn I, Saturn V, Buran and Soyuz. Actually, STS have the two informations (launches & landings) in the cell "launches". --FlyAkwa (talk) 21:24, 26 July 2011 (UTC)
 * It is still a small minority, and in any case the number of landings is not relevant to its performance as a launch system. -- G W … 22:06, 26 July 2011 (UTC)
 * Why then is "landings" present in the line of the STS ? Your point of view is not shared by all other participants.--FlyAkwa (talk) 22:38, 26 July 2011 (UTC)
 * The Shuttle was part of the entire STS launch system. Landings are unique to launch systems that land. Capsule type spacecraft are not part of the "launch system". If they are launch into orbit, the launch system has been successful. Maybe we should have three numbers (Launches that enter the correct orbit, total launches, and successful launch system returns, where applicable. user:mnw2000 22:53, 26 July 2011 (UTC)
 * I feel like hairs are being split here to specifically single out the shuttle for a difference definition of "launch". As far as I am aware, the launch of STS-107 was a success when the orbiter reached orbit successfully.  No other vehicle is expected to meet the criteria that the shuttle is in order to call a launch successful.  Why?  Jparenti (talk) 09:53, 31 July 2011 (UTC)

Sorting numbers not working
When sorting by the number fields, the LEO number were not working. I started to replace the number with the nts tag so that the field would sort properly. user:mnw2000 01:37, 2 August 2011 (UTC)
 * Sometimes if theres no space between the number and the reference it wont sort but it doesnt happen 100% of the time, not sure why. WatcherZero (talk) 11:45, 2 August 2011 (UTC)

Where Soyuz (and the entire R7 series) of launchers?
Did we miss something in the merge? No Soyuz? user:mnw2000 21:38, 2 August 2011 (UTC)
 * The merger is still ongoing -- G W … 21:50, 2 August 2011 (UTC)

Already unmanagable and not completed yet
I said it before and I will say it again, this page is being swamped in minor variants, in fact it should be renamed page of retired delta configurations... Seriously one entry for each main series rocket, we dont need a seperate entry for every possible combination of strap on boosters and upper stages that flew a single time. WatcherZero (talk) 22:38, 2 August 2011 (UTC)
 * I agree. We should only have one entry for each launcher (Delta 2, Delta 3, Delta 5). Otherwise, this will get too big. user:mnw2000 02:56, 3 August 2011 (UTC)
 * Two problems with that. Firstly, since this article is supposed to allow readers to compare and sort orbital launch systems, removing some simply because you don't like its length would make it far less useful. The payload capacity of, for example, a Delta 7320 is much lower than a Delta 7920, so a single entry would not be representative. The same goes for the Delta IV Medium and Heavy. Secondly, where do you draw the line? You need an arbitrary inclusion criteria, and I thought the whole point of the merger was to eliminate arbitrary criteria. -- G W … 07:01, 3 August 2011 (UTC)
 * It was okay before where it showed payload ranges, you knew the launcher could be variably configured to launch the desired payload, infact most launchers rarely launch their maximum payload, their fuelled only to the level required to launch the weight of the payload on that mission.. 14:50, 3 August 2011 (UTC)WatcherZero (talk)
 * It is a case of maximum capacity, not what they actually launch. If it were not, pretty much all of the launch systems listed would be perfectly capable of launching to LEO with no payload whatsoever, but their capacities should not be listed as being between zero and a maximum. Setting that aside for now, it does not resolve the issue of where to draw the line, without introducing more arbitrary criteria. -- G W … 21:33, 3 August 2011 (UTC)

Merger Complaint
why was there a merger of all the Launch Vehicles?? now the page is impossible to navigate, and there is no way of telling which class the Launch vehicle belongs to. I say we go back to the old format, where there were different pages for different types of launch vehicles. — Preceding unsigned comment added by Midgetman433 (talk • contribs) 21:25, 3 August 2011 (UTC)
 * The "classes" were just something a few editors made up. The merger was conducted to remove them, and base the lists on non-arbitrary criteria (although it now seems that some editors want to introduce new arbitrary criteria). In any case, if you read above, there was a poll which found unanimous support for merging the articles at that time. -- G W … 21:33, 3 August 2011 (UTC)


 * furthermore, just how is the page impossible to navigate? There should be no need to split the article to address that.  If anything the split article was even harder to navigate.Zebulin (talk) 03:49, 4 August 2011 (UTC)

The main problem is there is simply too much junk in the table, and since not all the entries have values, it doesn't really sort well. I will suggest two improvements: Tarl.Neustaedter (talk) 20:32, 5 August 2011 (UTC)
 * Put obsolete and not-yet-operational in their own tables
 * Merge entries for large numbers of related launchers (e.g., all the atlas variants).


 * I have to agree. The table is getting out of hand. There are so many versions of Atlas, Delta, etc. Can we all agree that, for example, all Atlas V launches, should be included on one line? I recommended a summary section below. However, the main table needs to summarize each launcher (regardless of configuration based on a strap on boosters). (Updated)

user:mnw2000 23:25, 5 August 2011 (UTC)

The above grouping sounds reasonable. We should try to preserve the variety of capabilities within the families in the individual columns - e.g., For Ariane 4, we should list the mass-to-LEO as "4600 - 7000", to accommodate the capacities of the various configurations. It might also make sense to move the original portions of the tables were going to merge, into the main articles for each booster family, so that there are readily-accessible tables in those articles with the information that will be glossed over here. I'd still like to see Operational in a different table than Retired or in Development, rather than just merely color-coded. For the purposes of what's available as launch systems, the obsolete and in development rockets are simply noise. If this sounds reasonable to other editors, I'll volunteer to do the grunt work. Tarl.Neustaedter (talk) 22:36, 6 August 2011 (UTC)
 * The question which I have raised repeatedly, and to which I am still yet to get an answer, is how is it decided which launch systems get their own entry, and which do not. The above list seems to explain why - no such criteria exist. To give a couple of examples, ignoring the fact that the Atlas V Heavy is a cancelled system with no place in the list, it is just a different "configuration based on a strap on boosters" [sic], so should by your own devices be merged into the Atlas V entry. Since there was no "Delta 1", I'm assuming that category covers everything from the original Thor-Delta up to the Delta 5000, ignoring the fact that just about every component was changed significantly between these variants. The Delta II is a much closer evolutionary step, yet it has its own entry. -- G W … 14:34, 10 August 2011 (UTC)

Yup, this merger is a real clusterf&$k. It was much more navigable as 5 separate launch weight classes! — Preceding unsigned comment added by Doyna Yar (talk • contribs) 22:46, 6 August 2011 (UTC)


 * Please explain what you mean by "more navigable". How could needing to memorize 5 different arbitrary class definitions and needing to know in advance which range in which to look for a given launcher even qualify as "navigable" much less "more navigable"?Zebulin (talk) 18:52, 7 August 2011 (UTC)

Weight classes are OR. The unified list is an improvement, even when under construction. A better distinction in my opinion would be to remove the retired and cancelled launchers to their own list. One reason: that list grows without limit. The current and development launch systems naturally will stay a manageable size, since the world's launch demand at any given time is finite. --IanOsgood (talk) 16:44, 7 August 2011 (UTC)
 * I don't understand the rationale behind separating active and retired systems, other than to make the table appear shorter. Surely the point of having a sortable table here is to be able to compare all of the systems by any of the details shown. A split list would not enable someone to compare past and present systems in order of, for example, capacity, to see how it has changed over the years. -- G W … 14:34, 10 August 2011 (UTC)
 * Now that I've played with sorting a bit more, I also like having the unified table. Sorting by Status or First flight puts the active launch systems on top. Perhaps that would make a better default sort than alphabetical? Having an initial view that shows only retired systems could be off-putting. (I'm only guessing at what is bugging everyone else. Maybe not all browsers are able to do table sorting?) --IanOsgood (talk) 15:13, 10 August 2011 (UTC)
 * The reason to dislike keeping the obsolete (and in development) systems merged into the operational systems is simply that there are so many of them. If you're interested in which launchers are capable of dealing with a given payload, all the noise of the launchers that aren't available just gets in the way. Tarl.Neustaedter (talk) 18:20, 10 August 2011 (UTC)
 * How are retired launch systems any less relevant than active ones? -- G W … 18:37, 10 August 2011 (UTC)
 * Retired systems are differently relevant than active ones because they don't exist today. Sorting launch weights of Space Shuttle vs. Saturn V isn't particularly meaningful - they never overlapped, and never launched comparable types of payloads. If all you're interested in is a massive table of meaningless numbers, sure, mix together everything. Might as well add in Jules Verne's stuff too, in another shading of "fictional" (if you aren't interested, just ignore that shading, of course). If someone is interested in "What can be launched now", the enormous number of obsolete and retired launchers are entirely irrelevant and get in the way. Same for "in development", where some or all of the numbers may be vaporware. Tarl.Neustaedter (talk) 07:24, 11 August 2011 (UTC)
 * Okay, fair enough, let's remove the rockets that are "in development", since they have not yet flown and their specifications are subject to change. Your comment about fictional spacecraft is a straw man, I have at no point advocated that fictional launch systems should be added to the list, on the contrary I have been strongly opposed to the inclusion of concept and cancelled launch systems, such as the Atlas V Heavy and Ares. "If someone is interested in 'what can be launched now'" then they can sort the list by status. Can you provide any evidence to support your claim that most users would be interested in that, and not, for example in how the payload capacities of rockets built in the 1960s compare to those currently in service? I don't see what relevance your Saturn vs Shuttle argument has, since under your proposed system they would both be in the same list. Also, setting aside the fact that I do not consider a lack of "overlap" a sufficient reason to split, since no system has a fixed service life there are plenty of cases where two contemporary launch systems would end up in different lists because one was retired prematurely; for example the Soyuz-U first flew in 1973 and is still in service, whereas the Atlas II, which first flew in 1991 was retired in 1998 (or 2005 if the even more stupid idea of merging all variants goes through). I don't even understand the rest of your argument. -- G W … 09:11, 11 August 2011 (UTC)

Definition of heavy lift
I have previously looked for a reliable secondary source for the lift classifications that are widely used in Wikipedia for "small-lift", "medium-lift", "mid-heavy lift", and "heavy lift". I was unsuccessful. I did find a workable reliable source for "super-heavy lift" in the Augustine Commission report, and have previousl placed that source in several of the applicable articles.

Does anyone have a good source for the upper and lower weight/mass classification of all of these rocket classes? Since these are terms that are used in the industry, we ought to use the same weight ranges for any WP articles using the terms. But since this is Wikipedia, they ought to be sourced as well. Cheers. N2e (talk) 17:41, 21 September 2010 (UTC)
 * I agree. I think it will not be easy to find such source - most probably there would be announcements like "Medium-lift Launcher XXX with capacity of YYY" and also conflicting (one company considers YYY to be medium, another company - heavy), different criteria (LEO, GTO, GEO) and different launcher versions also complicate things... Alinor (talk) 15:24, 22 September 2010 (UTC)
 * I'm with N2e here; why do we use the ranges that we do to split up the different launch systems? I understand that sources use different names (such as medium-lift, and heavy-lift) to describe different launch systems, but where does the range 20000-50000 actually come from? Mlm42 (talk) 20:49, 15 December 2010 (UTC)
 * What do you propose? Alinor (talk) 14:51, 27 December 2010 (UTC)
 * And just to clarify - I'm the one that put the upper border (50000) after finding the Augustine source, but I don't know who put the lower border (20000) and how it's sourced (maybe there is a source in the history edit-line?) Alinor (talk) 06:55, 29 December 2010 (UTC)

I saw, , and  edits (by IP, no comment on edit-line). You know that I'm against indiscriminate adding of 'citation needed' tags and especially about the indiscriminate deletion of material (if it follows the adding of tags). Also, for the divisions of the list articles, I'm not sure that 'citation needed' is the right tag to put after "This is a list of launch vehicles capable of lifting between X and Y to LEO" - but I understand the request to have X-es and Y-es mentioned in outside sources. As explained above this is not so easily achievable for multiple reasons. But anyway, the edits I mention here go in the opposite direction (too far, IMHO) - they copy the heavy/super-heavy source (the only one that we have so far) to all other X-es and Y-es. I can't find on the pages mentioned in this references or even in the whole Augustine report any other of the X-es and Y-es besides the heavy/super-heavy. So, maybe these should be reverted (but be careful, the last one contains other edits, unrelated to this issue). Alinor (talk) 12:41, 13 April 2011 (UTC)


 * I agree Alinor. I can only find the super-heavy line defined/described in the Augustine report.  So that report ought not to be used to support the other definitional limits for "heavy" or "medium" etc.  N2e (talk) 06:36, 14 April 2011 (UTC)


 * All of the boundaries are entirely arbitrary. I remember several discussions regarding where they should be set for the lower-capacity articles, and the suggested values were accepted with little or no evidence presented. I think the current way in which the articles are split is not sustainable, and I would strongly support merging to a single list in order to eliminate these spurious definitions. -- G W … 08:46, 24 July 2011 (UTC)
 * The articles clearly need to be merged. The existing demarcations are at best borderline original research and do nothing to improve wikipedia or serve the readers.Zebulin (talk) 15:11, 25 July 2011 (UTC)

Merger proposal

 * Comparison of small lift launch systems, Comparison of medium lift launch systems, Comparison of mid-heavy lift launch systems, Comparison of heavy lift launch systems and Comparison of super heavy lift launch systems into Comparison of orbital launch systems

As discussed above, the current arrangement of these articles is based on numbers which have been pulled out of thin air, and original research. Having the list split has also led to several other issues, with users asking why a specific launch system is not included (or attempting to add one) when it is listed under a different category. It has also led to disputes over the categorisation of systems which can place heavy-class payloads to higher orbits, but only intermediate-class payloads to low Earth orbit due to structural constraints. Finally, discrepancies between the formats have led to some contradictions developing: for example the Ariane 5G/GS is included both here (where all Ariane 5 variants are counted together), and in the Mid-Heavy list (where they are counted separately). Energia-Buran is similarly counted twice.

Merging the articles would primarily allow the spurious class definitions to be eliminated. It would also allow greater standardisation to occur, and force the same format to be maintained. I would also suggest that some thought be given to merging Comparison of solid-fuelled orbital launch systems into the final article as well, as it seems to be serving little useful purpose. A "Fuel type" column could be added to the combined list if necessary. -- G W … 18:29, 25 July 2011 (UTC)


 * Support -- there are no sourced criteria for dividing these launch systems up as is presently done, and the current lists do cause confusion, as per nomination. Moreover, there has been an evolving rough consensus developing on the Talk pages over the past half year or so that the existing structure is not sustainable.  N2e (talk) 04:42, 26 July 2011 (UTC)


 * Support -- All launch systems should be in one article. We can either have seperate sections for manned and unmanned, or GTO and LEO, etc. We can also use a more sortable table that would allow us to seperate the different "classes" based on thrust, or payload to LEO, etc. We should probably also put the "retired" launchers into a separate section. user:mnw2000 17:13, 26 July 2011 (UTC)
 * I would be opposed to separating the list based on an arbitrarily selected criterion such as performance, application, etc. Having separate tables or sections would make the sorting functions of the tables unusable, making it harder to compare systems. It would also do nothing to resolve the primary reason why we are merging these articles, which is to eliminate arbitrary splitting of the list, be that across several articles, or several sections/tables in the same article. I would also point out that there is a sum total of one launch system which has been used exclusively for manned flights; all other manned launch systems have also made unmanned launches, so that criterion would be ridiculous. -- G W … 22:12, 26 July 2011 (UTC)
 * Support -- If the articles had already been merged there would clearly be no incentive to split it up. The size of the combined article will still be quite modest.Zebulin (talk) 17:17, 26 July 2011 (UTC)


 * Support -- The discrimination may be similar case to WP:OC. All launch systems should be comparable and sortable. --Gwano (talk) 20:46, 26 July 2011 (UTC)


 * Support -- Let me clarify my suggestion of sections. I meant to suggest that active, under development and retired/cancelled be separated by sections. The single table of all launchers, whether they are active, under development, retired or cancelled will be very long. Especially if we include retired and cancelled which could be quite large. Remember the Thor launch system? Maybe we should have two sections, "active and planned" and "retired and cancelled". user:mnw2000 16:24, 28 July 2011 (UTC)
 * If we split the table, we won't be able to sort it properly. Given that this is a comparison, it makes sense that you should be able to compare the launch systems. Excluding cancelled launch systems will prevent it becoming ridiculously long. True, there could be quite a lot of entries for rockets like Thor and Delta, but they are the exception rather than the rule. How about just making sure that the table is fully sortable by status? -- G W … 20:16, 28 July 2011 (UTC)

Further discussion
It seems clear that there is consensus to merge, and since WP:MERGE allows the nominator to close discussion after a week where there is unanimous support for the merger, I have done so and will proceed with the merger. Several issues were raised with the format of the article, specifically whether the list should be split within the single article, and on exactly which columns should be present. No consensus has emerged on these issues, and since eliminating the payload classifications was the primary objective of the merger I will leave everything in one table for now unless a strong consensus to do otherwise emerges. Either way, discussion should continue regarding the format of the article. -- G W … 20:43, 1 August 2011 (UTC)

Merger reversal
The most useful criteria for division of launch vehicles is their lift capability. This is how the articles were created in the first place and this is how the aerospace community looks at them. Just google "Small Lift", "Medium Lift", "Heavy Lift", "Super Heavy Lift" and you will see how often these terms are utilized. It's inappropriate to merge the articles as bureaucratic solution to the problem that nobody found a source for the classification values. Here it is:

NASA Space Technology Roadmaps - Launch Propulsion Systems, p.11

There you see a table showing:
 * Small 0-2t
 * Medium 2-20t
 * Heavy 20-50t
 * Super Heavy >50t

As you can see actual Medium category covers both "mid-heavy" and "medium" articles - so these two should be merged, but not the rest. I will add the source to the launcher comparison articles and to the template. — Preceding unsigned comment added by 95.87.244.157 (talk) 19:12, 16 August 2011 (UTC)
 * FYI, the Wikipedia mid-heavy / medium division was performed much more recently than the rest. Funny that you want to merge them! --IanOsgood (talk) 16:32, 17 August 2011 (UTC)
 * Since there were others issues at stake here as well, I have reverted your unilateral action. There was a consensus to merge, and that should be respected until a consensus to do otherwise is formed. Now yes, a single NASA document does give us something that we can used to site mass categories, however I have three issues with it. Firstly, I find it interesting that with the exception of the mid and mid-heavy categories being a single item, the categories are identical to the random numbers that we pulled out of our backsides when these articles were first written. The report post-dates the existence of this article, so we cannot rule out the possibility of circularly referencing the c**p that we started with - the document contains no references so we don't know where they got it. Secondly, the document states that "the LPSTA team developed a representative launch vehicle manifest...with launch vehicles categorized as:...", which suggests the categories were chosen specifically for this report, and are therefore not representative of the entire industry - we shouldn't base the entire categorisation system on a single, obscure document - why are their arbitrary numbers any better than ours. Finally, the report specifies that "Reflecting the mission requirements and the technology plans of the Agency", which again shows that the categories are not representative of the entire worldwide industry, and were never intended to be. I feel that regardless of the existence of this document, going back to splitting by payload capacities would be a woeful mistake, and the current (new) structure should be maintained. -- G W … 19:57, 16 August 2011 (UTC)
 * The "problems" you mention about the classification source - first you imply that the NASA report is copying Wikipedia status quo classification (I think there is a noticeboard checking sources for WP:CIRCULAR compliance) - I find this very unlikely, especially when it's not the same (there is no "mid-heavy" category there).
 * That division was made more recently: check the history. It is all very arbitrary. --IanOsgood (talk) 16:32, 17 August 2011 (UTC)
 * Much more probable explanation is that Wikipedia editors who made the initial articles were basing them on primary sources that they didn't bother to mention and NASA report utilizes the same or similar primary sources for its classification. Second, you say that "categories were chosen specifically for this report" - but I don't think so - you can see many other NASA (and other) sources utilizing the same categories in many different contexts - the issue we had so far, that we didn't have a source that mentions all of the categories AND all their lift capacity borders. In the present report a manifest is developed, but it doesn't say that the categorization of launch vehicles is developed in the report (in 2010), it simply says what classification it utilizes - and there is nothing showing that it isn't the regular NASA classification, e.g. this isn't some report-specific unusual copyied-from-Wikipedia classification. Third you mention the words "Reflecting the mission requirements and the technology plans of the Agency" - but these are about the launch vehicle manifest developed, not about the launch vehicle types classification utilized for arranging the vehicles in the manifest.
 * The merge was closed by the proposer after only a brief discussion. This is not how it should be done. Especially when the status quo lasted for so long. And the decision was "merge" only because the established classification was without a source (it had only a source for heavy/super heavy border. That source was wrongly labeled as "failed verification" after a brief period of "quotation requested" - such quotation now provided). Now we have a NASA source about the classification.
 * So, there is no consensus for merge (merge discussion time too short/closing too hasty) - if you want, please open a new merge request that takes into account that now the classification is sourced.
 * The versions of the articles that reverse the merge and add the new source and the quotation of the old source are:, , , ,
 * The small/medium/heavy/super heavy status quo classification is not "pulled out of thin air, and original research" - it just lacked a source for some of the borders, but now we found such source - from NASA.
 * The other issues such as users asking where a vehicle is mentioned (in the list covering the respective range), or some rockets listed in two lists, because of significantly different modifications - these are minor (and can be dealt with inside the status quo framework) or not problems at all IMHO. In any case these are not a reason to change the established classification. You can see that almost all of the commenters supporting the merge do so because of a lack of source for the classification. Now we have such a source.
 * Another problem with the merge is that its result is a unwieldy long table (even before merging all of the articles), it deleted various information (even major things like the number of successful flights). Jeffsapko (talk) 08:58, 17 August 2011 (UTC)
 * One of the things you see when you look at a unified table, is that the 2/20/50 ton division used before in Wikipedia and that one NASA report was completely arbitrary. It does not line up with the actual modes, neither historical nor modern. That has always bugged me about the division of these tables in the past. A unified table is a vast improvement there. Let the readers sort the data and draw their own conclusions. --IanOsgood (talk) 16:32, 17 August 2011 (UTC)
 * The "problems" you mention about the classification source - first you imply that the NASA report is copying Wikipedia status quo classification (I think there is a noticeboard checking sources for WP:CIRCULAR compliance) - I find this very unlikely, especially when it's not the same (there is no "mid-heavy" category there).
 * That division was made more recently: check the history. It is all very arbitrary. --IanOsgood (talk) 16:32, 17 August 2011 (UTC)
 * Where to start. Firstly, when I was still a fairly inexperienced editor I was involved in one of the discussions regarding where the boundaries should be. I proposed one or two, not because I had seen sources, but because they seemed like reasonable numbers, and those boundaries were adopted. Also, the heavy/super heavy boundary was based on the misinterpretation of a source. You claim that there are "many other...sources utilizing the same categories" - I have seen absolutely no evidence that such sources exist, and you have not provided any additional references to support your claim. You claim that "there is nothing showing that it isn't the regular NASA classification", but that is an appeal to ignorance, since there is nothing showing it to be the regular NASA classification either, and the onus is on you to prove that it is a widely used system. In response to your third point, again the onus is on you to prove that it is more widely used, and yet again you have provided no evidence to back up your position.
 * The merger discussion was closed after a week as there was unanimous support for merging the articles. That is fully acceptable under current Wikipedia policies (proposer can close in support of merger if there is a unanimous decision after a week, see WP:MERGE), and given the poor state these articles had been in for so long because of the previous status quo. The decision was not made only because of the sourcing issue, but it was a contributing factor. If you actually read the discussion, you will see that there were other concerns given in support of merging the articles. The Augustine report was discredited as a reference in this context because it was discovered the classifications that were claimed to be contained within it did not, in fact, exist.
 * The lack of consensus is in your opinion only and defies the fact of the discussion above. Since the discussion was completed within existing policies, its result reflects the current consensus for what to do with the article. Therefore it is you who is taking disruptive unilateral action by repeatedly reverting an edit made as the result of a legitimate merger discussion, and it is you who must start a new discussion should you wish to undo the merger.
 * Again, which issues are minor and which issues are major is, by your own admission, entirely your opinion. It changes nothing. Finally, the removal of the number of successful flights was because nobody could agree on a neutral way of determining what constituted a successful launch. -- G W … 00:34, 18 August 2011 (UTC)
 * I agree that it is flattering for a Wikipedia editor (and the project as a whole) if a NASA report utilizes a classification he invented (e.g. WP:OR). And this will be a pure WP:CIRCULAR if have any evidence that this is the case. But we don't have. What we have is page11 of a NASA report. If you claim that this report is WP:CIRCULAR, then please put the issue at the appropriate Wikipedia noticeboard.
 * The articles were not in a "status quo poor state before the merge". And if they were - we can improve on any issues you mention (whether I think they are minor or not) without disregarding the NASA classification and merging.
 * Another procedural issue - the removal of "successful launches" information (and the other removed-in-the-merge infos) is neither discussed nor agreed by consensus. It was done together with the merge without discussing it. Yes, a few of the figures are debatable and that's why it has an explanatory note. In fact, the "debate" is only about a few cases (1st Energia launch mostly) and this is not a reason to remove such important information altogether. Success metric is very important for any equipment, especially for launchers where costly items (e.g. 20t satellites or interplanetary probes costing billions) or human lives are at stake.
 * The prior-source-finding merge discussion proposer says "Merging the articles would primarily allow the spurious class definitions to be eliminated." - the primary reason for the merge is the lack of source for the classification. Of the 4 users that had time to participate 2 also stress only or primarily this issue. This lack is corrected now. So, please stop using that prior-source-finding merge discussion as if there is a consensus to merge. Let's restore the status quo (with the source added) and then you can start a real merge discussion based on substance - citing different reason (from lack of source).
 * How the status quo was reached: In 2007 the "heavy" article is started (definition >20t LEO). In 2008 "medium" article is started (definition 2-20t LEO). In 2009 the series is finalized with the "small" article (definition <2t LEO). In 2008 a "mid-heavy" article is started, but outside of the LEO capacity continuity - it's started as a "competitors to Ariane, e.g. 3-9t GTO". In 2009, following the Augustine report the "super-heavy" is started (definition >50t LEO, sourced) and "heavy" is re-defined (20-50t LEO instead of >20t, upper border sourced). In 2010 the "mid-heavy" was re-defined into LEO capacity continuity (10-20t LEO instead of 3-9t GTO) of the rest of the articles.
 * The 2009 Augustine report isn't "discredited" - it says on p.64-66: "5.2.1 The Need for Heavy Lift ... require a “super heavy-lift” launch vehicle ... range of 25 to 40 mt, setting a notional lower limit on the size of the super heavy-lift launch vehicle if refueling is available ... this strongly favors a minimum heavy-lift capacity of roughly 50 mt ..." Afterwards, we have the 2010 Launch Propoulsion roadmap report that follows-up on that assessment and gives the same figure for "super-heavy".


 * So, we have a sourced classification with three borders: LEO 2, 20, 50t. For the 50t border we have also a source describing on 2-3 pages why it's 50t (allows the flexibility to lift two “dry” exploration elements on a single launch). So, we have even a sourced explanation WHY it's 50t - I wouldn't call this "arbitrary". "Heavy", "Medium/Intermediate", "Small" lift launch vehicles are also quite commonly utilized terms - and while it's rare to see ALL categories in the same source TOGETHER with all borders (that's why these remained without sources so far) there are many reports and other materials discussing these different classes of vehicles and their utilization, manufacturing/supply constraints, effect on ICBM manufacturing, state security, etc. Of course the distinction between "Heavy" and "Super Heavy" emerged recently - when human exploration beyond LEO came to the agenda. So, the 50t border is clarified. I agree that it would be good if have additional sources showing why NASA selected 2t and 20t as the other two borders. Maybe the reasons are similar - 2t and 20t are around the minimum requirement for some capability? Anyway, even without explanation - we have a source showing that NASA utilizes these borders - and there is no reason to disregard that and adopt some different arbitrary Wikipedia-editors preferred criteria.


 * The purpose of launchers is to put payload in orbit. The main metric here is the weight of the payload. It's natural that launchers are classified according to their lifting capability. So the NASA source showing launcher classification by lifting capability can't be disregarded. Jeffsapko (talk) 09:01, 18 August 2011 (UTC)


 * Well, as I am one of the orginal editors who commented on the mess that was these five comparison articles prior to the merger, I should probably weigh in. However, there are so many different subtopics being discussed in all of the above dialog, one doesn't know where to start.


 * First off, I would say that the merge has occurred, per consensus, and is therefore, the new status quo. So it would probably be useful to start thinking, and discussing, in terms of improving Wikipedia with subsequent changes, rather than in terms of "merger reversal."


 * Moreover, it might be good to address any number of incremental changes to the article, or future split of the article into >1 pieces. But in my view, it would be better to see clear proposals, and then build consensus on, each of the topics individually.  This is for several reasons, but one of them is that if I were to weigh in right now on even a small subset of the topics, my post would seem like a stream of consciousness and be difficult to follow (few might read it, or grok it), and thus any new consensus would be likely to elude us.  I think that is largely the state of the discussion in this subsection above.  Cheers.  N2e (talk) 20:12, 18 August 2011 (UTC)
 * The "merge" result has multiple flaws, some of them: it's not finalized and it's not a merge, but (partial) merge plus undiscussed removal of major information - successful launches. Also, I see that some launchers were deleted altogether - Atlas V Heavy, STS-total-mass-to-orbit (vs. Shuttle-payload-to-orbit). Thus what I see is a hasty decision to merge because of lack of classification source, then something else is done, then a classification source is found (thus the merge decision is invalidated), but some editors insist that the not-exactly-merge-result is a status quo. Also, as another editor said in below section - very few editors still support the merge and more object. Jeffsapko (talk) 06:52, 19 August 2011 (UTC)

Format of a unified article
Should the above merger proposal be successful, there are several differences between the lists which would need to be standardised, as well as some issues with other arbitrary and misleading information which should be replaced.
 * Columns: All of the articles contain a column for the vehicle's name, its country of origin (termed either "Country" or "Origin"), manufacturer, unit cost, payload and cost per kilogram to LEO, payload to GTO, launch record, status and "active period". Most of the lists also contain costs per kilogram to GTO. In addition, the mid-heavy list contains a column entitled "exploitation". This is less than clear, but it appears to list the LSPs associated with that launch system. The super heavy article contains a column for payload to TLI. It should be noted that in the small lift article although a payload to GTO exists, it is mainly used to present payloads to SSO. My suggestion would be that all of the columns which exist across all articles be retained, with the exception of payload to GTO. In its place, a "payload to other orbits" column could be added, giving payloads to GTO, TLI and SSO, plus anywhere else associated with individual rockets. Guidelines should also be put in place to use comparable data for the LEO payload, and to specify the altitude as well as the orbit regime, as one vehicle's payload to an 800 kilometre polar LEO is not comparable to another vehicle's payload to a 200 kilometre equatorial LEO, however under the current arrangement they would be listed in the same column with no caveats. The cost per kilo to GTO column would be hard to justify if the GTO payload is not explicitly stated for every system, so it should be removed. Additionally, the "exploitation" column adds little, and could easily be removed. For the country of origin, I would suggest using "Origin" as the column title, per a discussion on the issue held in August 2008 when the column was reintroduced.
 * Inclusion of cancelled launch systems: This isn't even handled consistently within the articles, let alone between them. Some launch systems are included in the tables, whilst the majority are not included. Earlier discussion found no consensus to include systems which did not reach flight status. Since the whole point of the merger is to eliminate the use of arbitrary criteria, and the inclusion of vehicles such as Ares and Atlas V Heavy seem to be based on how far advanced their development was at the time of cancellation, I would suggest that these be removed. Systems actively under development (development, not study) can still be included, but should be removed upon cancellation. Systems which are not actively under development but which could be returned to development if required (eg. Atlas V Heavy) should be removed since in principle any cancelled launch system could be brought back into development if enough money were presented. It can always be re-inserted if it enters active development. Listing cancelled launch systems below the table is all well and good, but with the merger this would result in a very long list. Therefore I would suggest that this be split off to a separate list, such as List of undeveloped orbital launch systems, or Comparison of undeveloped orbital launch systems. Equally, launch systems which are no more than design studies, such as Falcon XX, should not be included.
 * Launch record column: There is no one set of criteria for determining the outcome of a launch. This has been one of the main flashpoints in discussions related to these articles. There have been heated discussions ad nauseum regarding the numbers of successful launches made by certain launch systems, particularly Energia, the Space Shuttle, and the Saturn V. At the end of the day, this is always going to be an arbitrary criterion, and open to interpretation. Therefore a summary comparison of launch systems is not the place to present this information, so I propose that the launch record column be renamed "Launches", and simply be a count of the number of launches, regardless of outcome. A decision should be reached regarding whether or not launches made by orbital launch systems, but not intended to reach orbit should be included in those launch systems' launch tallies (they currently are in the small lift article, but not in any of the others). If they are included, values for the number of orbital launch attempts and the total number of launch attempts could be given, however it should be made clear that launches intended to reach orbit which did not do so would still be listed as orbital launches. A suggested format would be X (Y), where X is the number of orbital launches, and Y is either the number of suborbital launches, or the total number of launches. Y would be omitted where no suborbital launch attempts have been made.
 * Breakdown by variant: Some of the lists provide a breakdown of individual variants of a launch system, such as distinguishing a Delta II 7925H from a Delta II 7320, whereas others do not (such as the heavy lift list, which contains a single entry for all five Ariane 5 variants. Since each of these variants has slightly different specifications, and potentially a significantly different payload capacity, I would suggest that the detailed breakdown become the preferred format.
 * "Active period" column: This is confusing, since it presents the development dates for launch systems which have not entered service, and service dates for launch systems which have. I would suggest that it be replaced with two columns: "First flight" and "Last flight", whose purposes should be fairly self-explanatory.

The resolution of these issues would simplify the proposed merger of the articles. -- G W … 22:11, 25 July 2011 (UTC)

Another option which I am starting to favour might be to have several articles covering the same launch systems. With several other comparison articles across the site, multiple tables are presented, displaying different specifications. In this case the article would be too long for multiple tables, so each table could have its own article. Comparison of orbital launch systems could show basic data such as manufacturer, name, etc. We could then set up Comparison of orbital launch systems by payload capacity, Comparison of orbital launch systems by technical specifications, and so forth. This would allow more data to be presented than could be easily displayed by a single line table. This proposal does not have to be implemented at the same time as the merger; the combined article could be split later. All launch systems would appear in all lists. -- G W … 16:13, 26 July 2011 (UTC)


 * The columns "Cost", "Cost/kg", and "Cost/kg" doesn't have many sense, because of differents epochs. It will be better to have two columns (each), with "cost at this time" and "cost constant dollar". The column TLI is needed for heavy and very heavy launchers, and will be blank for lighter launchers. --FlyAkwa (talk) 16:43, 26 July 2011 (UTC)
 * So surely it makes more sense to have a column for LEO, and a column for "other orbits", which can be used for TLI, SSO or GSO, or even all three, depending on the launch system. I am concerned that constant dollar costs may not be available without original research. -- G W … 17:37, 26 July 2011 (UTC)
 * Constant dollar is, in fact, really easy to compute with this [website]. Actually, the table often give us the "dollar at this time", and we have also the dates. Then we can compute easily the constant dollar, that is better to compare costs between launchers. I think the column "other orbits" might be not easily readable, if all GSO, SSO and TLI are given for a launcher... On the other hand, there might be too many columns... --FlyAkwa (talk) 21:18, 26 July 2011 (UTC)
 * "Compute" implies original research. We are trying to move away from that. -- G W … 22:01, 26 July 2011 (UTC)
 * No no, no original research, simple conversion of datas in the actual table. I could do that if you want. --FlyAkwa (talk) 22:24, 26 July 2011 (UTC)
 * You need to be able to provide citations to back up the numbers. -- G W … 22:34, 26 July 2011 (UTC)
 * Long list of responses; I would add firstly the idea of proliferating lists comparing different attributes should be prevented, thats the whole reason for the proposed merger in the first place. I would also argue against removing success/failures as it gives a good visual indicator of why certain launchers were cancelled and their level of use. Some people try and list launches as 'partial sucesses' for example launching a payload into the wrong orbit requiring it to be retasked to a different purpose or its life significantly shortened expending the vast majority of its fuel reaching a higher orbit so only complete successes be included. Even when these lists are on the same page I would argue to leave them as four seperate tables as one combined table would be unmanagable. I would say that all columns should be sortable alphabetically or numerically. Finally as to breakdown by version this should only occur if a developed variant exists e.g. stretched or a new engine, if a design was originally intended to have a payload range via reconfiguring the number and type of boosters then its payload range should be listed to prevent proliferation. — Preceding unsigned comment added by WatcherZero (talk • contribs) 17:25, 26 July 2011 (UTC)
 * The reason for the proposed merger is to reverse the proliferation of lists comparing the same attributes with indiscriminate inclusion criteria, and to eliminate the number of arbitrary criteria used in this article, thereby cutting down on original research. Continuing to list separate tables for each of the articles merged would defeat the object of the merger. -- G W … 17:31, 26 July 2011 (UTC)