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After a video by What About it discussing water deluge systems I got to thinking about it. I remember hearing that the Russians don't use water deluge systems.

Not sure if these would be considered a reliable sources but I found something on Quora and Reddit:

On Quora: Because Cape Canaveral is at sea level, digging a deep hole for clearance would be problematic. Because Russia's cosmodrome is at a higher elevation, it's easier to dig a big hole for exhaust deflection.

On Reddit: In the harsh Russian winter, the water would freeze.

Also in the pictures for soyuz launch I don't see any water. https://en.wikipedia.org/wiki/File:Soyuz_expedition_19_launch_pad.jpg https://www.defenseworld.net/news/26790/SpaceX_Rocket_Launch_on_May_27_to_Break_Russian_Monopoly#.X0jkfchKiM0 http://www.russianspaceweb.com/kanopus-v5-v6.html

But Wikipedia says that the launch pad at the Baikonur Cosmodrome for Energia rocket had a water deluge system. Ok that's a yes for at least one Russian launch pad. https://en.wikipedia.org/wiki/Sound_suppression_system

Do the Russians use a water deluge system when launching their current rockets? I'm looking for some reliable source discussing the lack of use of water deluge systems when launching their current rockets.

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  • $\begingroup$ There don't appear to be water towers at the Baikonur Cosmodrome. Perhaps you could pump water from tanks on the ground, but if that would work why don't NASA do that -- why build a tower unless you have to? So the lack of water towers would seem to imply that they don't. However this is just speculation (hence a comment). $\endgroup$ – tfb Aug 28 at 12:20
  • $\begingroup$ @tfb: It's actually the other way around: a pump system that is able to pump that amount of water in such a short amount of time would be really complex and really expensive … and only used for a couple of seconds every couple of weeks. Gravity, OTOH, is free. That's why water towers were invented in the first place, because you can use cheap, low-power continuous pumps to add gravitational potential to the water, then instantaneously release it. So, if you don't see water towers at a launch site, you can be pretty darn sure they don't have a deluge system. $\endgroup$ – Jörg W Mittag Aug 29 at 11:36
  • $\begingroup$ @JörgWMittag: Yes, I agree. I think also that a gravity system has the huge advantage that it's fail-safe: if your pumps suffer from some failure then you're in big trouble, while for a gravity system, once you've opened the valve there is nothing to go wrong. $\endgroup$ – tfb Aug 29 at 11:45
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I believe the answer is that no, they don't. Below is a quote from this page by Franco Carnevale, who works for Immarsat and has been involved in launches from Baikonur:

The sound pressure level of large rocket engines has been measured at greater than 200 decibels – one of the loudest man-made sounds on earth. I have always been interested at the reasons for the lack of a massive water deluge system at the Proton launch pads. Their western counter-parts dump a massive amount of water to absorb the roaring noise from the first stage engines.

This is not the case for Proton which only uses a small amount of water to keep fire and heat under control. The lack of a water deluge system is compensated through the vehicle configuration, good acceleration during take-off, and the lower levels of acoustic noise that comes from the propellant fuel engines that are used, compared to a solid engine and rocket structure.

So I think that is reasonably conclusive: there is no water deluge system for current launches from Baikonur.

Note. The above applies to the Proton launch system: it's still possible that the Soyuz launch system does use water deluge. I have not been able to find anything at all definitive about the Soyuz launch system. However there are many videos of Soyuz launches which do not show steam, so I believe it's fairly safe to assume that it does not use water deluge.

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    $\begingroup$ How about the Soyuz launcher? I believe that's also the case for it, but your answer only addresses Proton. There are many more Soyuz than Proton launches. $\endgroup$ – Organic Marble Aug 28 at 13:07
  • $\begingroup$ @OrganicMarble: good point. I can't find anything which talks about Soyuz launches and water. But there are many videos of Soyuz launches from Baikonur which don't show steam, so I believe that it does not use water deluge either. I'll add a note to the answer. $\endgroup$ – tfb Aug 28 at 13:48
  • $\begingroup$ Even Soyuz ST doesn’t use a deluge $\endgroup$ – Antzi Aug 29 at 1:59
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    $\begingroup$ I'm particularly curious about how N-1 suppressed sound during its four launches... $\endgroup$ – Anton Hengst Aug 29 at 22:36
  • $\begingroup$ @AntonHengst: I believe I read somewhere that it did use water deluge, but can no longer find that. $\endgroup$ – tfb Aug 30 at 11:24
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There are two big problems with acoustic energy during a rocket launch:

  • Sound pressure waves hitting and damaging the launch pad.
  • Sound being reflected off the launch pad and hitting and damaging the vehicle.

If you look at the launch mount at Baikonur, you can see that the vehicle is actually suspended over the side of a cliff of a man-made crater:A Soyuz rocket is erected into position at the Baikonur Cosmodrome's Pad 1/5 (Gagarin's Start) on 24 March 2009. The rocket launched the crew of Expedition 19 and a spaceflight participant on 26 March 2009.NASA/Bill Ingalls / Public domain

That means that compared to e.g. the Falcon 9 launch mount at SLC-40, the launch mount is open at the bottom, the reflecting surface is much farther away, and the reflecting surface is angled so it reflects the sound away from the vehicle and the launch mount.

As a result, the energy that needs to be controlled is much lower, and can be compensated for by a sturdier launch mount and vehicle.

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