Talk:Sukhoi Su-75 Checkmate

F-35 "light to medium"?

may compete with the Lockheed Martin F-35 Lightning II and other aircraft of the same light to medium-weight category

Putting the F-35, at 13,300kg empty (F-35A) one of the heaviest single engine fighters ever made, into the "light to medium-weight category" seems a bit ironic. Empty, it's even heavier than the two engine Rafale, Eurofighter and F-15C and only slightly less heavy than e.g. the Tornado GR4.

Stealth aside, and in my personal opinion, the emphasis on the Su-75 being low maintenance and able to operate from short airstrips is much more reminiscent of the Gripen, but from what is known so far, I expect it to be significantly heavier than the very lightweight (6,800kg) Gripen, maybe around the 11,000kg range. Aragorn2 (talk) 10:04, 22 July 2021 (UTC)

Designation

I would assume that the internal prototype name is T-75 (the Su-57 had a prototype name T-50). Rostec has a first interview online where they dont use a number but they repeatedly name the project "ЛТС Checkmate" (mixed cyrillic/latin russian/englisch), see [1]. Guidod (talk) 16:27, 22 July 2021 (UTC)

The Su-75 designation does seem to be a misunderstanding of the project name, but i wouldn't be surprised if Sukhoi goes along with the misnomer Anthropophoca (talk) 02:45, 15 November 2021 (UTC)

"Ruddervators require sophisticated flight-control systems"

Why would ruddervators require sophisticated flight-control systems? For my model plane the conversion from pitch and jaw to ruddervator settings is simply pitch + jaw for one, and pitch - jaw for the other ruddervator. — Preceding unsigned comment added by 92.10.236.193 (talk)

I agree, that is a good question - they are used on several gliders and ultralights and just controlled with mixing bellcranks. This may need a better explanation in the article, but the cited refs doesn't explain the claim made. - Ahunt (talk) 23:16, 6 November 2021 (UTC)

Super and transsonic flight requires all moving control surfaces, to prevent control reversal due to shock formation. This effectively increases the gain on the transferfunction of the elevator, or equivalent ruddervator, reducing the stability margin. While instability is desirable for highly manouevrable fighter aircraft, (hence the stability margin is a negative distance), it requires increasingly sophisticated fly-by-wire and flight-computer, and increases trim drag. If the plane is too unstable, it may be difficult to control or react quickly enough, particularly in gust or high alpha. Which is what killed forward swept wings like Su47 & X29 — Preceding unsigned comment added by 137.222.95.58 (talk)

Super and transsonic flight requires all moving control surfaces - not true, see Concorde, B-58 Hustler and hundreds of other examples. - Ahunt (talk) 14:54, 9 June 2022 (UTC)

The OP likely meant "it requires all moving (aka movable) control surfaces /to move to control the aircraft/. Is probably a bad/direct translation from Russian which uses a more relaxed word ordering. — Preceding unsigned comment added by 83.240.63.17 (talk)

It may well be a poor translation, but still doesn't make sense like that - all current supersonic aircraft have moveable control surfaces. - Ahunt (talk) 17:04, 6 August 2022 (UTC)

X-32 the first plane to introduce a DSI? Dodgy footnotes??

I think you'll find Vought's XF8U-3 Crusader III vigorously disputes this statement since it flew with one close to 42 years before the X-32. Might also want to check those footnotes (16,17 & 18,19,4,20). 16 is a broken link, and 18,19,4,20 are irrelevant to the statement about the Boeing X-32. Take out the part about the X-32 being the first to introduce a DSI, and footnotes 18-20 become relevant to the original sentence stating the Su-75 having a DSI. (Chocko2-14) — Preceding unsigned comment added by 14.2.114.87 (talk) 07:42, 7 December 2021 (UTC)

I have fixed footnote 16, which says The overall inlet design, called a diverterless supersonic inlet or DSI, moved from concept to reality when it was installed and flown on a Block 30 F-16 in a highly successful demonstration program. The flight test program consisted of twelve flights flown in nine days in December 1996. If you are going to claim that an earlier design used a DSI then you will need to cite a ref for that. - Ahunt (talk) 13:07, 7 December 2021 (UTC)

Can you provide a source that proves the XF8U-3 Crusader III actually has a DSI? The closest thing to a source I could find was the aircraft being the lead image of the Diverterless supersonic inlet Wikipedia article (which is also captioned with a [citation Needed] tag). The aircraft's own Wikipedia article doesn't even mention DSIs at all.

To my knowledge the actual first aircraft to fly with one was a modified F-16 in December 1996, which predates the X-36's maiden flight by about 4 years.
Xiongu (talk) 17:17, 6 April 2023 (UTC)

Issue with "Checkmate" Designation

Using the name "checkmate" is premature.

NATO reporting names for fighters start with "F". Consistent with this various sources, such as on reddit, have dubbed this "Femboy" based on the second syllable starting with B. While this is not the final NATO name for the jet, the article probably should at least acknowledge the usage in popular culture. 98.45.185.205 (talk) 20:27, 15 March 2022 (UTC)

References

"Checkmate" is the manufacturer's name, not the NATO reporting name, which is why we don't call it the NATO name in the article. Reddit is not a reliable source, so, no, we won't be mentioning "Femboy", even as a rumor, until it receives significant coverage in multiple reliable sources. BilCat (talk) 21:21, 15 March 2022 (UTC)

Cope cages have made it into media coverage, I am hopeful that the "Femboy" name will achieve that same goal. The Su-75 is just not relevant in the news cycle right now. 2003:6:31DE:7B86:AC59:9E59:9440:175B (talk) 02:34, 27 March 2022 (UTC)

When it is in a WP:RS and not before. Wikipedia is not Reddit. -Ahunt (talk) 13:13, 27 March 2022 (UTC)

Exactly. In addition, the "nickname"/slur has also been showing up in vandalism on the Sukhoi Su-57. This indicates that, however it started, it's now in Internet meme territory, and those are almost always non-notable to the aircraft articles themselves, as it's not actually about the aircraft type at all. BilCat (talk) 01:43, 30 March 2022 (UTC)

Using checkmate goes against policy for all other Soviet and Russian aircraft, where reporting names in the language of the page is preferred, with local nicknames in body text — Preceding unsigned comment added by 92.40.204.107 (talk) 16:24, 2 June 2022 (UTC)

"Checkmate" is not a "local nickname" or NATO reporting name, it is a manufacturer's name. - Ahunt (talk) 16:47, 2 June 2022 (UTC)

Should the fact Sukhoi gave their fighter aircraft an English manufacturing name be noted in references? As far as I know that hasn't happened before. Additionally, briefly mentioning that it does not yet have an official NATO reporting name would be nice, and could somewhat help avoid vandalism, at least by the misguided. Satv9 (talk) 19:14, 2 June 2022 (UTC)

I doubt they gave it an English name; I assume it's a translation. VQuakr (talk) 20:03, 2 June 2022 (UTC)

The Su-75 is intended for export, and marketed toward India, Vietnam, and "African countries", according to the sources. Since English is a worldwide language, and spoken in most of the target markets, it makes sense that they would choose a name in English, probably along with the Russian equivalent. Which came first is probably a "Chicken or the egg" question. BilCat (talk) 20:25, 2 June 2022 (UTC)

If a NATO reporting name becomes more recognizable to English-language readers than Checkmate, changing the article title at that time should be uncontroversial. Until then, this is the best title. VQuakr (talk) 18:00, 2 June 2022 (UTC)

We don't generally title Russian aircraft articles with their NATO reporting name, but use a local name if it's well-known and well-documented. It's a highly contentious subject, and that's the compromise. Some Russian-speaking editors even try to remove the NATO name altogether, but they've never gotten a consensus for that, and probably never will. BilCat (talk) 20:25, 2 June 2022 (UTC)

Patent application

Russian patent application RU2770885 C1 appears to relate to SU-75. It describes a single-engine multirole stealth fighter by the Sukhoi company, and the drawings match the appearance of SU-75. Moreover, the application was filed a day before the start of the MAKS 2021 airshow, where the SU-75 was introduced. Just because it does not explixitly mention ”SU-75” is not a reason to remove mentions to it. Patent applications typically do not include such designations. As long as the patent publication is described using proper qualifiers, the reference can be very informative to many readers. For example, the figures show the air intake path to the engine and the shape of the weapon bays. ​

Your ref does not mention the Su-75, so this does not belong in this article unless a reliable source can connect the dots. Your guess that this is about this aircraft is strictly WP:OR. - Ahunt (talk) 22:39, 5 May 2022 (UTC)

It is common practice to file a patent application right before showing off a prototype product. This should only be a question of phrasing. The following sentence should contain no controversial statements, as all the elements are verifiable: Russian patent publication RU2770885 C1 was filed by Sukhoi a day before the start of MAKS-2021 and describes an aircraft having a similar appearance to the SU-75. 2001:14BA:A089:6200:9D63:2457:E0BE:583 (talk) 14:36, 6 May 2022 (UTC)

describes an aircraft having a similar appearance to the SU-75 - there is the issue, that is WP:OR. We need a ref that says this patent has anything at all to do with this aircraft and is not just some general patent unrelated to any specific aircraft. - Ahunt (talk) 23:00, 6 May 2022 (UTC)

It is not original research, as the fact is clear to every reasonable person by simply looking at the pictures, thus easily verified. For example, note that the article on the Tokyo Tower mentions Eiffel Tower as the inspiration (which is indeed very likely), apparently without explicit sources. Regarding linking to patents: For example RSA (cryptosystem) article links directly to the associated US patent even though the patent does not call the algorithm RSA. Also the article on RADAR links to patent applications that do not use the terms RADAR (that was given to the system later). It is silly to try to always avoid primary sources, as long as they are appropriately described. A link to a primary source can avoid various misinterpretations. In my opinion, interpretations on what information can be included should typically err on the side of giving the reader relevant information. 2001:14BA:A089:6200:9D63:2457:E0BE:583 (talk) 17:21, 7 May 2022 (UTC)

Patents are WP:PRIMARY sources. To be clear even if the application specifically mentioned the SU-75 or an independent source linked the two, this patent application still shouldn't be linked from the article. VQuakr (talk) 00:36, 7 May 2022 (UTC)

So basically you have nothing that ties this patent to this aircraft, except your own personal claim that the drawing looks like an Su-75? I think we can close this discussion, unless anyone has anything else to add. - Ahunt (talk) 18:24, 7 May 2022 (UTC)

References