Template talk:Rocket engines

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Rocketry Template‑class

This template is within the scope of WikiProject Rocketry, a collaborative effort to improve the coverage of rocketry on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.RocketryWikipedia:WikiProject RocketryTemplate:WikiProject RocketryRocketry articles Template This template does not require a rating on Wikipedia's content assessment scale.

Some sort of classification based on upper stage / booster engine would be very useful. Not sure how to represent this in the template, but the way U/S and other engines are built is quite different, and there are a lot less of these around. — Preceding unsigned comment added by Savuporo (talk • contribs) 01:00, 14 September 2015 (UTC)[reply]

Believe it or not, there are many engines in this template where we just list the family and it has both booster and upper stage applications. This was a standard Soviet practice for ICBM. SpaceX also does that. So, in the end, you would end up with more engines listed.Baldusi (talk) 16:06, 8 October 2015 (UTC)[reply]

Shouldn't this template include the three new solid rocket motors that successfully flew on the ESA Vega flight in February? The Vega has the P80 first stage, the Zefiro 23 second stage, and the Zefiro 9 third stage. — Preceding unsigned comment added by 157.166.167.129 (talk) 23:00, 24 February 2012 (UTC)[reply]

Some missing engines include RD-171 RD-108 RD-0110 ArkianNWM (talk) 17:47, 7 August 2012 (UTC)[reply]

I've added quite a few more. Some need an article, though. I'm working on that. I started with the RG-1/LOX first because those where the more historically important. Now will concentrate on the Dnepr-1 and Rokot propulsion. But to fill this entry all you need is to look at the list of flown orbital vehicles and check for their propulsion. Nothing of the Tsyklon, Kosmos-1, Kosmos-2I, Shavit or the Indian solids are mentioned.

User:Baldusi (talk) 21:00, 1 June 2015 (UTC)[reply]

What engines are appropriate for this list? Is it only for launch vehicles? Only for engines that have flown? Undergone significant development/testing? Thoughts? ArkianNWM (talk) 17:10, 7 August 2012 (UTC)[reply]

I believe the scope is too ambiguous. Personally I want to know about Space related rockets, not whatever the AIM-7 uses. And what does it means flown? I've been adding anything that's done at least a powered hop. But there have been a lot of engines that have gone through a test stand (like the RD-270), and that aren't on this list, even though they needed a lot more effort, and advanced the technology and used up a lot more money than something like the HD5. So in that sense is also a problem. I've seen the French version of this template that it doesn't limit itself to flown rockets, and projects that haven't done a single fire test, like SpaceX's Raptor are there.

Then you have the issue of relevant subject. I simply don't see the 1.8KS7800, AIM-7 motor the as significant to space flight. Besides, most rocket motors are military and mostly classified. Thus, it would setting up an impossible task. But, there are a lot of solids that I have to add and have great significance to space. I'm referring to the sounding rockets, which are mostly solids. In fact, many are military surplus. And usually, a lot more information is available.

Then we have the definition of flight. How do you differentiate a [[[JATO]] from a space related motor? At what point a sub orbital flight stops being an aviation flight? Why does a ten meters hop is more space related than a 5,000km flight?

I'm just putting all the scope considerations here. I just hope that someone responds because this is getting very lonely.

Baldusi (talk) 12:54, 19 June 2015 (UTC)[reply]

Hi Baldusi, thanks for your efforts to try to rationalize and improve this template. I'll respond! But I'm not sure I know what the best thing, or even a sensible thing, to do with it is.

Navigation templates on Wikipedia are tough. One part of the reason is that, in general, nav templates have no citations (and citations would be kludgey in a NavTemplate) yet NavTmeplates often make claims that end up being legitimately debatable by different editors. For example, in this template on rocket engines, the template makes the claim that each of these (ostensibly notable, since they have their own WP article or redirect) engines has "flown", but editors may naturally want to draw the line differently as to what exactly that means. So I think the discussion here is important.

I share your concern that these sort of templates shouldn't be too long, with "too many" links. I've never worked very much on NavTemplates, but you might find some guidelines at Wikipedia:Navigation templates or get help from a wider community of editors with more template experience by asking over at Wikipedia:WikiProject Templates, or at Wikipedia:Templates for discussion.

On the rocket engine questions specifically, I'm not sure what makes sense. It seems to me that use in orbital spaceflight may be a key distinction. For example, does it make sense to have two templates? One for rocket engines used in orbital spaceflight and one for the myriad engines used for suborbital missiles, rockets, JATOs, etc.?

Antoher question is: What is the cutoff for the template? If flown, then does, for example, Merlin 1A, Merlin 1C, and Merlin 1D make the cut, as each were important engines, or does only a single link to a family article make it, since they (currently) are described in the English Wikipedia in a single article? But if the latter, then do the various Russian named engines with unique numbers and unique WikiArticles make the cut, even though many of the minor engines would be, say, much less important to spaceflight then the Merlin 1A/1C were?

I will try to be a colleague and watch this Talk page with you, even though I don't have good answers, or even strong opinions on the directtion of the answers, for you. Cheers. N2e (talk) 12:20, 21 June 2015 (UTC)[reply]

The way I understand this template, is that it is trying to list all of the engines that have ever flown on a major rocket powered vehicle, and not just a subset of those. My issue then is that the classes that these engines are arranged into don't cover all categories. More directly, the classes are too narrow. LOX/LH2 are not the only cryogenic fuel combo, LOX/RP1 are not the only semi cryogenic fuel combo, and there are engines that use no cryogens but also do not use hypergols. I know that there are a couple of engines currently undergoing testing that use LOX/LCH4 which are both cryogenic. I don't know if any engine systems exist which would be appropriate for this list that use these, but LF2, NO2, and HTP are potential oxidizers that are excluded from this list and there are many fuels other than RP-1 that are excluded from this list including gasoline, LCH4, and Syntin. ArkianNWM (talk) 17:10, 7 August 2012 (UTC)[reply]

You can see that I've arranged a bit the classification, and added quite a bit of engines. I've been adding categories where it makes sense. But for solids, where each engine has a unique formulation, it simply doesn't makes sense. For liquids, it sort of makes. But that's why I did a section for Cryo (H2/LOX) and on for Cryo (CH4/LOX). Those are the only two cryogenic mixes that I've found. For Semi, you'll notice that I left the Semi-Cryo (RP-1/LOX) and added the Semi-Cryo (Other) with each subsection being the mixture. And I did something similar with hypergolic. Which is an issue because some Semy-Cryo are, in fact, hypergolic. And in general some engines are arranged by country of origin and others simply by propellant. I'll keep expanding the number of engines and then give the categories some thought.

I believe that we still have to change the scope a bit. I'll discuss that under Scope.

Baldusi (talk) 12:39, 19 June 2015 (UTC)[reply]

The template currently shows RD-0146 as a "flown" engine. When, where, on what vehicle? (sdsds - talk) 23:29, 19 July 2014 (UTC)[reply]

Vinci was included when this template was just "rocket engines," but it has not yet flown... and probably won't for several years A(Ch) 00:17, 27 July 2014 (UTC)[reply]

We have seen both the Blue Origin's BE-3 and the SpaceX SuperDraco fly sub orbital. Should this classify for this? I understand that the BE-3, which went to 97km of altitude should be put here, and it's supposed to cross the Kármán line, is a "space" rocket. I'm not sure about the SuperDraco since it's not a main rocket engine (but neither is the RD-8). Should the SpaceShipTwo RocketMotorTwo be considered? Why isn't the X-15 XLR99, that actually made it above the Kármán_line in 1963? In other words, when we talk about flown do we mean orbital, or do we include suborbital? Let's remember that there are a lot of rockets used for sounding rockets, too. Thus, I believe that we should either change the title a bit (adding the orbital word), or add a bunch of rocket engines. (Baldusi - talk) 13:03, 28 May 2015 (UTC)[reply]

I've seen that from its very origin, this page has included aircraft rocket engines. Thus, I'm adding any non orbital flown engine that I can actually find.

(Baldusi - talk) 14:15, 12 June 2015 (UTC)[reply]

I've been thinking how to divide the solid motor section. Just from getting some of the space related families, it is getting big. I did a first approach on the country of origin. The other possible divisions I can think of are: 1) Fuel (APCP, HTPB, etc.). But the possible mixtures are huge and that's information that's very difficult to acquire. Specially if due diligence is done cross checking. 2) Casing: Segmented/monolithic and metal/composite. Just 4 combinations seem like little. 3) Use: missile/booster/space launch core/upper stage/kick stage. Could be, but solid motors are notable for being very flexible in this regard. So, I'm leaning on dividing by country of origin, as long as it doesn't grows too much. But for this I believe that we should have a serious discussion on the scope of this template. Almost every military rocket has a solid motor. And some have been used for non-military space launches (like Taurus). So I believe that some serious scoping should be discussed and written. Baldusi (talk) 18:16, 18 June 2015 (UTC)[reply]

Well I think it will be more useful for the encyclopedia reader if a distinguishing choice in the template is about the rocket engine itself, and not merely what factory or what geographic area of the Earth it was made in. So it seems to me that your options #1, #2 or #3 might be better. If fuel type is difficult to find sources for, then throw out option #1. Seems like no.2 or no. 3 would be fine. Or maybe even some measure of power (thrust times duration? or whatever the proper metric would be): small, medium, large, and HUGE (e.g., SSRB's and whatever might have been used on Buran?, etc.). Just a thought. N2e (talk) 04:11, 30 June 2015 (UTC)[reply]

I've been working on this template a lot. I've written no less than 20 new articles, added quite a bunch of engines, motors and categories. But the template lacks a clear scoping. One underlying problem is that I've been seeing a clash between Wikipedia:WikiProject Spaceflight, Wikipedia:WikiProject Rocketry and Wikipedia:WikiProject Aviation! In fact, the template is currently claimed by Wikipedia:WikiProject Spaceflight.

As currently defined, the Template is only for flown engines, but it doesn't define what sort of flight. Thus it mixes aircraft, space and military applications. And yet it is only filled by space related engines. Thus, I would like to propose to branch the templates in one for spaceflight specific engines (where we might discuss is suborbital or space project like Project Morpheus should be included. And some fire tested engines might go there, too. I believe that Aviations should have a separate Template. And so should rocketry. I will invite members of those projects to this discussions.

Please understand this is my first discussion and if there's some formal way of doing votes and such I will require some assistance.

Baldusi (talk) 15:58, 30 June 2015 (UTC)[reply]

Baldusi -- I've made a substantive response to your branching topic, below. However, let me offer to help on process if you'd like on how to make your first proposal most productive. I've done a number of them myself, and participated in hundreds. If interested in this sort of meta-assistance, ping me on my Talk page. Or ask the question on your Talk page, and invite me over there to offer assistance. N2e (talk) 18:44, 30 June 2015 (UTC)[reply]

I certainly think it is too big and too hard for readers to quickly make sense of, so I agree it needs to be split in some manner. - Ahunt (talk) 16:15, 30 June 2015 (UTC)[reply]

I agree. The template has become too large through the wonderful emergent work of her editors. Good work, Baldusi! So we are 3 for 3 today on branching the template. The question to discuss may be how, or by what distinguishing features of these rocket engines. I've added a couple of thoughts in previous Talk page sections, but no one clear way stands out. N2e (talk) 18:39, 30 June 2015 (UTC)[reply]

I'm a newcomer here, but here's an organization that makes sense to me: separate templates for launch vehicle engines, orbital maneuvering engines, attitude control thrusters, military missiles, amateur rockets, and aviation, with some engines showing up in multiple templates as appropriate. Breakdown by propellant type seems to make sense for spaceflight-related engines. I'm not sure how you would assign this between the three mentioned wikiprojects; there is overlap especially between spaceflight and rocketry. Perhaps you don't need to. Sanchazo (talk) 18:51, 30 June 2015 (UTC)[reply]

I would like to get a few more opinions. But I will be developing a proposal during this week so we can discuss it. When I have the proposal ready for discussion I would kindly ask all of you to ping somebody else from Wikipedia:WikiProject Spaceflight, Wikipedia:WikiProject Rocketry and Wikipedia:WikiProject Aviation. I might be a member of the first two but I'm the one doing the proposal so I would like at least two other member per project. If this is fine in a week or so I will ping you so you can see it and ask for further opinions. Baldusi (talk) 15:26, 1 July 2015 (UTC)[reply]

Just a thought here, but is a nav box even the way to go for rocket engines? We don't have nav boxes listing all the automotive engines, ship engines or aircraft engines. Why? Because there are far too many of them. In time there will be more and more rocket engines flown and there will just be too many of them for a nav box. Perhaps this should all be handled with categories instead, as it is with other engine types? - Ahunt (talk) 14:33, 5 July 2015 (UTC)[reply]

Wouldn't we convert it into a set of list articles then? (and a nav template to navigate between list articles) -- 67.70.32.20 (talk) 05:56, 6 July 2015 (UTC)[reply]

Actually, that was were I was moving with my proposal. I'll go and put it down here. Baldusi (talk) 12:28, 6 July 2015 (UTC)[reply]

Proposal[edit]

My proposal is to reduce the scope of this template to "Orbital Launch rocket engines that have flown". And make a series of lists for the rest. We would also have to work on the rocket categories, too. And I would probably help do a rocket nav template (Rocket Types/Rocket Concepts/Rocket Technology/History/Lists would be the main subjects). But that should be discussed on each individual Talk page. So, without further ado:

• I propose that we change the scope of this template to "Orbital Launch Vehicle's flown rocket engines". The rest would go elsewhere. Baldusi (talk) 12:28, 6 July 2015 (UTC)[reply]

• SUPPORT—this navbox will be much more tractable by narrowing it's scope to just the rocket engines for orbital launch vehicles that have actually flown, and the navbox will be much more likely to be kept up into the future, as editors come and go. Also, while I think List of .... articles are better for the other lists, there is nothing in your proposal that would prevent interested editors from creating navboxes as well. Good proposal. N2e (talk) 15:16, 6 July 2015 (UTC)[reply]

• Support - sounds like a good way to go to me. - Ahunt (talk) 15:55, 6 July 2015 (UTC)[reply]

• I support making list articles out of this template (list of cryogenic rocket engines, list of semi-cryogenic rocket engines, list of hypergolic rocket engines, list of liquid fuel rocket engines (a list of lists for the three prior sublists, and listing any other engines not covered under prior lists) list of hybrid rocket engines , list of solid fuel rocket engines ; and a keep this navtemplate name to navigate between the lists, and between Liquid-propellant rocket / Solid-propellant rocket / Hybrid rocket ; An "Orbital Launch Vehicle's flown rocket engines" if we create such, would be a new template, but it should be a list article first, describing the circumstances of its use (date, what rocket vehicle, etc) ; that would remove WPSPACEFLIGHT from this template (placing it only in WPROCKETRY, and thus out of the Spaceflight templates category), and move it to the Orbital template/list and the engine lists. -- 67.70.32.20 (talk) 02:37, 7 July 2015 (UTC)[reply]

COMMENt: I don't have any particular problem with creation of a few good List of ... articles. But I will point out that, if the list has more info than merely the link to the title of the blue-linked article, then all claims need to be cited with reliable sources, per standard WP:V. This can be quite tedious, and is work that needs to be done by whatever volunteer editor creates the List article and wants to add any addtional claims to it. Note that many list articles are made that are short citation support, and thus are not likely to remain in place long term.

So in short, this proposal, as stated, is about what to do with this particular navbox article. The other List articles that may, or may not, be created are a bit beyond the scope of the proposal that was made above. N2e (talk) 05:39, 7 July 2015 (UTC)[reply]

We can create the lists as is by conversion, and add {{unref}} while we work through the list articles, because WP:NOTFINISHED. I doubt they would get deleted while we're sorting things through. -- 67.70.32.20 (talk) 04:39, 8 July 2015 (UTC)[reply]

• Support I like the simplicity of this proposal. "Orbital Launch Vehicle flown rocket engines" sounds good to me. Sanchazo (talk) 17:09, 7 July 2015 (UTC)[reply]

• Support Baldusi has done great work on this template; I heartily support the user's proposal. A(Ch) 17:44, 7 July 2015 (UTC)[reply]
• Support I support Baldusi's proposal. Reducing and simplifying this template seems the right thing to do. I also agree with creating "list of .." articles to manage the huge list of rocket engines of different types spanning many contexts. There might even be a nav-template made up of categories to connect all this information. --Guyver (talk) 19:03, 7 July 2015 (UTC)[reply]

• Support I pretty much have the same opinion as Guyver on creating the "List of..." article and a nav-template. For the 'Flown Rocket Engines Template' I have just two suggestions. First one is to keep things the same standard, for example right now not in all areas there is a country sub-category. My other suggestion is also to put propellants and types into one column, for example what you did with Cryogenic propellants, do the same for the others (In the name hypergolic or cryogenic etc. can be on top and underneath will be the mixture). I think this will keep it more neat. All in all well done! Hammer5000 — Preceding undated comment added 15:29, 13 July 2015 (UTC)[reply]

Well, it looks like there is a consensus. I will make the changes and explain the scope during this week. Baldusi (talk) 16:27, 23 July 2015 (UTC)[reply]

Today I added the new Vinci engine under development by Airbus Safran Launchers for the Ariane 6 second stage. Baldusi reverted me, pointing out that the template's scope is limited to rocket engines that have already flown. Now I see the 2015 discussion which I had missed, however I think it would be informative for readers to see the upcoming engines which are in active development by reputable companies (not necessarily planned engines which are only on the drawing board and may never materialize). I would suggest adding them in italics, with a note at bottom of the template. There must be very few such engines, so they wouldn't clutter the template. Opinions please. — JFG ^talk 16:31, 13 September 2016 (UTC)[reply]

Well, since we have worked on improving the rocket engines articles, this template has exploded. I've already reduced the scope and branched out engines for aircraft, suborbital and spacecraft. And this keeps getting bigger and bigger. Personally I believe that making it compact by inlining the country of origin within each propellant type might be a good start. But may be another solution will be needed. Regarding the Vinci, it is in a very advanced readiness level. But there are a lot of engines that will debut an orbital mission between now and 2020. There's RD-181 this year, CE-20 this and the next, and the you have Newton Three, Newton Four, Ruderford, FireFly's, and may be even SCE-200. So a section for seriously ready engines might seem like a good idea.

The problem with that is that it's very difficult to scope in such a way that only "serious" engines are added. Just for starters, just getting info of engines that have started to be bench tested is difficult. And then not all bench tested engines will eventually fly. ULA is running a competition between RL-10, BE-3U and XR-5H25. RL-10 has flown orbital, BE-3U has yet to get to orbital speed, and XR-5H25 is just doing bench tests. Would we put the three? What if XR-5H25 is not selected, we'll we take it out?

And then you have the dangers of small start ups using that section to boost their PR campaign. Anybody with a pressure-fed design and a render of an orbital rocket will want to be there. Orbital flown is pretty clear, the rest is muddy waters. Those are the issues that we should work out before making such a change. But if you want to give it a try, I'm all for it. Something has to be done with this template. – Baldusi (talk) 18:27, 13 September 2016 (UTC)[reply]

Thanks for your feedback. My suggestions to move forward:

• List only engines in development which already have an article; this ensures notability per regular WP:N criteria.
• Group hypergolic engines by country like the others, not by exact propellant
• Display countries inline (I will experiment with this right now on the cryogenic section)
• Group engines by family, leaving one link per article (e.g. RD-107, 108, 117, 118)

Taking these steps should improve compactness and clarity. — JFG ^talk 01:19, 14 September 2016 (UTC)[reply]

 Some changes applied. I haven't touched the hypergolics yet, pending your approval for grouping them by country. — JFG ^talk 02:28, 14 September 2016 (UTC)[reply]

I like how it is looking. I didn't linked all variations of engines for the Russians since they tend to give each variation a new name, so I had to chose only the most important of each family. Also, looking at how it is looking, we might inline further the propellant type within each category (e.g. H2/LOX and CH4/LOX for cryogenic) since seldom used propellants like the RD-119 case or BE-4 and Raptor use too much space. But let me tell you that I like how its starting to look. – Baldusi (talk) 02:39, 14 September 2016 (UTC)[reply]

I think we can lump the odd RD-119 together with the other hypergolics, as it burns UDMH. Let me try to group by country without exact fuel details; I think two levels of classification are enough. — JFG ^talk 04:51, 14 September 2016 (UTC)[reply]

 Done – Please check for inaccuracies or omissions. — JFG ^talk 05:24, 14 September 2016 (UTC)[reply]

Yes, I like how it's looking now. There's just a little issue with the Soviet Union engines. In the time of the CCCP, most rockets were designed in Russia, but the RD-8xx were designed in modern Ukraine. I've moved the RD-843 since that was designed in modern times. But for the others, I would like to keep the historical source. An option I see is to rename Russia as Soviet Union/Russia, and that should keep the older RD-8xx in that line.

Once we settle this issue I will update the documentation. I see that I must make it clear that each engine should be put under the designer's country. Because some, like the RD-120, were designed in Russia but manufactured in Ukraine. – Baldusi (talk) 13:39, 14 September 2016 (UTC)[reply]

I agree with placing engines in their country of design. I was also thinking of distinguishing USSR from Russia but decided that simplicity was stronger than politics. — JFG ^talk 17:19, 14 September 2016 (UTC)[reply]

And based on the very informative "family tree" diagram of RD-120, I have now moved RD-8 to Ukraine, and added the RD-801 and RD-810 under development. Interesting to see that India got their SCE-200 design from Ukraine… — JFG ^talk 17:32, 14 September 2016 (UTC)[reply]

Well, I have redone the documentation. Among other things, I actually placed it in the documentation page. I think it is in a much better state now.

The only issue with placing the RD-8 in Ukraine is that it was done in the times of the Soviet Union. So you either move all RD-8xx to Ukraine, or keep the RD-8 in Soviet Union/Russia. I'm leaning to the former, though.

The RD-801/RD-810 is quite an issue for me. I wrote all the articles and did all the research. As far as I can tell from the drawings and specifications, Yuzhnoye Design Office designed the RD-801 for China to do their YF-100 and the RD-810 for India's SCE-200. But the only documentation that I've found on Ukraine and the YF-100 is a flat out denial in a WikiLeaks nopaper. I have deduced from the available information, that Yuzhnoye, which has been basically broke for a long time, designed both engines to India and China's requirements. But since they can't even afford to build one (and if they could they couldn't sell it due to MTCR), the just sold them the blueprints. This required that India and China to reverse engineer all the design and to actually develop a lot of materials. So, while Ukraine stills offers the RD-801/810, and they say they will use them on the Malyak, I believe they are the remnants of the original design. I would love to redo the family tree of the RD-120, but I can't without some very good citations. But to make this short, I believe they are just blueprints and should not be in this list. – Baldusi (talk) 18:42, 14 September 2016 (UTC)[reply]

Very insightful, thanks! Unlikely we'll ever see those phantom rockets Mayak and Tsyklon-4… Sad for the Ukrainian rocket industry, unfortunately. — JFG ^talk 13:34, 15 September 2016 (UTC)[reply]

Question on China: any clue about the SpaB-65 and SpaB-140C SRMs? I've seen a picture of Kuaizhou specs with a SpaB-100 too, but can't find much info beyond that. Also I suspect that Kuaizhou (KZ-11) and Long March 11 (CZ-11) are the same design, just named differently for military or civil applications. What do you think? — JFG ^talk 17:32, 14 September 2016 (UTC)[reply]

In short, the differences between CZ-11 and KZ-11 include:

CZ-11 is developed by CASC, while KZ-11 by CASIC;

1st stage diameter (2 m vs 2.2 m)

Technically, CZ-11 seems to be a direct descendant of DF-31 ICBM and uses the same traditional steel case, but KZ-11 uses a newly developed carbon composite case.

However I'm not sure about the following questions:

CZ-11's exactly designer/manufacturer inside the CASC group;

The relationship between CZ/KZ-11 and Kaituozhe-1/2 and their commercial derivative marketed by LandSpace/ExPace and CZ-6A's and CZ-8's solid boosters and their weaponized variants like anti-satellite weapons and boosters of hypersonic gliders;

KZ-11's historical or technical antecedents. Since the CASIC is a newcomer to the launch service market, I guess it's a clean sheet design, at least its first stage.

The relationship betweem CASC (and its subsidiaries esp. CALT and SAST) and CASIC and their products is ... very confusing. I hope someone can drastically improve their corresponding articles in wikipedia. -PSR B1937+21 (talk) 04:27, 16 June 2017 (UTC)[reply]

Since in this template rocket engines are classified by different storage temperature, I suggest using the term 'storable' instead of hypergolic. -PSR B1937+21 (talk) 04:05, 16 June 2017 (UTC)[reply]