# Talk:RS-25

This section has severely out-of-date info and could probably use some love. - Jadebenn (talk) 08:39, 9 June 2019 (UTC)

I couldn't see how many STS launches they were designed to do between overhauls (3 I think) or how many launches in total they were designed or intended for. Which parts had to be specially designed so that the engine was reusable ? How much did the design for reuse, increase the development cost and the cost per engine ? - Rod57 (talk) 12:08, 12 February 2020 (UTC)

In 1970 the design goal for the SSME was 50 flights before replacement, but I'm not sure what they were eventually certified for.
The original Rocketdyne turbopump bearings were only lasting for 2 fights, replaced later by P&W turbopumps. - Rod57 (talk) 09:42, 22 November 2020 (UTC)

Section 1.4.1 (Controller - Main Valves) mentions that the Chamber Coolant Valve (CCV) is 100% open at high throttle settings, "for maximum cooling," and is progressively closed at low throttle setting "for reduced cooling". This seems to contradict the schematic diagram of the engine in this same article (which is derived from various sources). The CCV appears to function as a bypass valve, bypassing the coolant plumbing and going straight to the preburners. Therefore, it appears (to this layman) that closing the CCV would actually increase the fuel flow through the nozzle and chamber cooling sections, as less fuel is able to bypass and would be then increasingly forced through the two sections of plumbing that provide cooling. If this is the case, my guess is that at lower thrust levels, the mass flow through the engine is less and therefore the regenerative cooling is reduced, so the CCV is closed to pick up the slack. Indeed, the source referenced at the end of section 1.4.1, reference 5, doesn't mention anything about "maximum cooling" or "reduced cooling," and simply states the valve positions for various throttle levels, which makes me think that these statements in the article are incorrect. Of course, I could be entirely wrong about this - perhaps someone more knowledgeable than me can elaborate.  — Preceding unsigned comment added by 67.83.150.17 (talk) 17:09, 24 November 2021 (UTC) 

To my enthusiastic surprise, a photo taken by me is used on this page. Can I get credit for it? It is currently labeled as being owned by someone else and all the data referring to date and camera settings are all wrong. Thank you Daj750 (talk) 18:02, 28 October 2024 (UTC)

Hi @Daj750:, sorry if nobody replied to you yet. This is a serious matter (and unfortunately not too uncommon) that Wikipedia can help you deal with. You can contact English Wikipedia admins by email for immediate response, and/or you can request copyright review on both Wikimedia Commons, or both. Review the instructions and include both this article page and the specific image that you are referring to, because it is unclear from your post which photograph you mean.  2A02:AA10:E777:9280:40F9:351D:F82B:9EEA (talk) 17:09, 9 October 2025 (UTC)

As the title says, the source from web.archive that cited says Chamber Pressure: 204.08 bar , 1 bar = 100 000 Pa, so it should be 20.408 MPa (2,959.93 psi), and metric units first. MrBart31 (talk) 08:31, 22 November 2025 (UTC)