Soyuz engine caps (?) question

[VaPaL]

I was looking some Soyuz pictures and saw this that I don't know what it is. Assuming that, for being red, it will be removed before flight, so maybe a safety equipment?

I'm refering to the red cylinder that the guy is working on. I don't even know how to search this, I tried "Soyuz engine caps" but the results were totally off.

 

[Gaarst]

There are some pipes coming out of it. It may be something to do with the Verniers' hydraulics.

Though the guy does not appear to work on the cylinder itself, but rather on some sort of servicing panel behind.

[VaPaL]

@Gaarst Those looks more like electrical wires, don't they? The boosters ones go to the vernier region, but the core one goes way down then enters the side of the core (looks like at last). And they are to loose to be kept during launch, loose enough to be burnt by the exaust.

[Ten Key]

I did some digging and I can't seem to find anything conclusive. Given the handles, the color and the loose hoses, I would be stunned if they weren't removed before flight. Part of the launch prep for the Soyuz rocket involves installing batteries, so it is possible the tanks are some sort of power supply. Another theory I ran across is that they are part of some sort of temperature and/or humidity control system. 

One thing I did notice is that these tanks seem to be missing from Soyuz rockets launched from the ESA's facility at the Guiana Space Center. . .

 

Roll out at the Russian cosmodrome. . .

 

The rocket below has reached the launch pad and the tanks are still attached. You can see the hoses go into the sides of the boosters. I found a basic diagram of those boosters (Pg 22 of this manual. WARNING PDF) and it looks like there are small peroxide and nitrogen tanks just below the kerosene tanks, and right about where those hoses look like they attach. Those red cylinders may be part of a gas purge for the peroxide tanks prior to filling. That's my wild guess.

 

 

In contrast, here are two pictures of a roll out at the ESA facility. Note the missing tanks.

 

[VaPaL]

@Ten Key Good hipotesis, it really look like they are going to those thanks, but the booster in the manual has a fin that these don't have, so could be a old version or something. The point you made about the Russian and French rollout is really interesting, I know that the French facility is more modern than the Russian, so I thought it could have a different ignition system and that thing would be ralated to it. But the Soyuz in Vostochny also have those things, and this facility is, as far as I know, more a like the French one. Also I found that the Soyuz ignition system uses hipergolic fuel, and by this manual (PDF) it appears that the hypergolic fuel is kept in the main fuel line.

Soyuz at Vostochny:

[kerbiloid]

Reds are protection cones inside nozzles.

Ignition system is 32 T-shape wooden sticks with primers

Spoiler

(src https://geektimes.ru/post/273782/ )

 

[VaPaL]

@kerbiloid I heard of that ignitions system before. But what are those red cylinders, near the sitted guy in the first image of the OP?

[magnemoe]

Does the drum on central stage extend into the air stream? 
It looks so to me

[VaPaL]

@magnemoe I don't recall anything extending on the Soyuz, but I'm not sure

[Nothalogh]

On 3/14/2017 at 8:16 AM, kerbiloid said:

Ignition system is 32 T-shape wooden sticks with primers

That is pure slavtech, right there.

And the most magnificent part is it works flawlessly, and has for 50 years.

 

[SuperFastJellyfish]

On 3/13/2017 at 5:51 PM, Ten Key said:

One thing I did notice is that these tanks seem to be missing from Soyuz rockets launched from the ESA's facility at the Guiana Space Center. . .

I skimmed Arianespace's Soyuz user's manual in search of what those canisters are for, and happened upon an image on page 120(of the .pdf) with a red canister visible at Kourou.  I couldn't find what they were for though.   

Edited March 23, 2017 by SuperFastJellyfish
wrong link :p

[Ten Key]

2 hours ago, SuperFastJellyfish said:

I skimmed Arianespace's Soyuz user's manual in search of what those canisters are for, and happened upon an image on page 120(of the .pdf) with a red canister visible at Kourou.  I couldn't find what they were for though.   

Good eye. I skimmed through that manual during my own search and completely missed that.

If we take the internal diagram of the Soyuz booster from page 233 of that manual and lay it next to a slightly enlarged cut out of the actual booster from that image. . .

 

. . .we can see that the line from that red external tank goes into the booster right where the peroxide tank would be. Both the nitrogen and the peroxide tanks are tori (donut shaped), so there's only one of each type of tank, even though the diagram makes it look like there are two of each. Nitrogen is fairly benign, but high-test peroxide likes to decompose on its own, and since the process is exothermic it's self reinforcing. In a sealed tank, this decomposition will cause the pressure to build until the tank ruptures. Those red cylinders may be used to mitigate pressure build up in the peroxide tanks, but I don't know why they'd be removed before roll out. As far as I can tell, the peroxide isn't added until the rocket is on the pad. 

[SuperFastJellyfish]

Fine work, Ten Key.  I think you're spot on! 

[Nothalogh]

17 minutes ago, Ten Key said:

Those red cylinders may be used to mitigate pressure build up in the peroxide tanks, but I don't know why they'd be removed before roll out. As far as I can tell, the peroxide isn't added until the rocket is on the pad. 

Perhaps they are part of an inert gas purge of the peroxide system

[SuperFastJellyfish]

I'm American so I'm not too familiar with liters, but on page 133 of that manual it says:
 

Quote

 

Industrial quality gases:

•Compressed air supplied through distribution network

•Nitrogen (GN2) of grade N50, supplied through distribution network (fromtanks) or in 50 l bottles

•Gaseous nitrogen (GN2) of grade N30 supplied through distribution networkonly in S3 area

•Helium (GHe) of grade N55, supplied through distribution network from tanks(limited capacity) or in 50 l bottles

•Industrial quality liquids:

•Nitrogen (LN2) N30 supplied in 35 or 60 l Dewar flasks

•Isopropyl alcohol (IPA) "MOS SELECTIPUR"

•De-mineralized water

 

After reading that, if I had to guess, I would say it's either gaseous nitrogen or gaseous helium in a 50 l bottle.  I don't know much about LN2, but I would think those hoses would be covered with frost if it was a liquid nitrogen Dewar.  I'm just an armchair nobody though so, here we are.   

[VaPaL]

I don't know, the more I look, more that hoose looks like an electric cable, or a bunch inside a hoose. I'm familiar with a russian turbopump that has an electrical heater in the bearings to prevent it from freezeing during cool/chill (?) down. so maybe this is related. 

@Ten Key It seems to me that the hoose enters the booster a little bellow those tanks more or less on the turbopumpo height. Don't you think?

But my guess is as good yours guys