Question on Proton launch infrastructure

[shoogerbrugge]

OK, a long shot, does somebody know why there is such a difference in Proton launch infrastructure.<br /><br />For example in the first picture<br /><br />click here<br /><br />and the following launch tower <br /><br />click here<br /><br />Why is there such a large difference, is the assembly in the later picture being done onside or what could be the reason

 

[CalliArcale]

Hope you don't mind the edit; if you want to make a link here you have to use the "url" tags. "link" tags don't work. (Read the FAQ for a complete list of available UBBCode tags.)<br /><br />The difference between those two Protons appears to be whether or not the service structure is in place around it. The first one has just been erected; you can see the erector to the immediate left of the rocket. The second one has been on the pad awhile, and the service structures have been erected around it so it can be serviced prior to launch. (Note: being on the pad "awhile" for a Russian rocket is probably less than a week. They don't let rockets sit on the pad for months like Americans sometimes do. It's a different philosophy, born of the early days of the Cold War ICBM age.) <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[shoogerbrugge]

Nope I dont mind the edit, tried to do it myself but didnt work somehow<br /><br />I see what the difference is now. Its just that I'd never seen a picture of a proton in the stage between placing it verticle and a few hours before launch.<br /><br />You see, both things are big events and pictures are frequently taken, but in the period in between, nada. I was wondering whether the Proton M had a complete automated launch (like the Zenit has) and earlier models not. But I guess I was wrong <br /><br />It seems that the first picture the upperstage shroud is covered in isolation material. Is this because the spacecraft and upperstage are already fuelled and need to be cooled?

 

[CalliArcale]

That is interesting stuff on the payload shroud; I don't think I recall seeing a cloth covering on a Proton payload shroud before. I would guess that you are right, that this has something to do with keeping the payload from overheating, but I don't think it has anything to do with fuel. Spacecraft are usually filled with hypergolic propellants; boil-off isn't so much of an issue there. And in fact, the Proton's first stage is hypergolic (nitrogen tetroxide and unsymmetrical dimethyl hydrazine; a popular combination in Russian vehicles). Let me just look up some basic factoids about the Proton M....<br /><br />Okay, Protons can be outfitted with a variety of upper stages. I couldn't get a clear answer on whether Proton M has a particular upper stage. If it's the Block DM, then it's cryogenic (LH2 and LOX), requiring more thermal regulation prior to launch. If it's the Breeze-M, then it's hypergolic and wouldn't need to worry especially about that.<br /><br />It may also have something to do with the actual spacecraft on that vehicle, or it could be a temporary piece of insulation to reduce heat loads on the payload prior to launch -- a "remove before flight" kind of thing, although I'd usually expect that to be painted some obnoxious color like bright red to make sure technicians remember to remove it. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[shoogerbrugge]

its a breeze M upperstage for sure. They only fly ProtonM/BreezeM combination or the ProtonK/BlockDM combination.<br /><br />All ILS missions are flown on the ProtonM/BreezeM combination, while all RSA missions are flown on ProtonK/BlockDM<br /><br />I don't know what the difference is between the ProtonM first 3 stages and the normal ProtonK.<br /><br />here is a better picture click here <br /><br />here is another one, but from the AMC-15 launch some time ago click overhere<br /><br />So let me get this right, the errect the Proton, clambs hold it stabel, the launch tower is moved in position for fuelling and last checks, moved back and countdown for launch starts.<br /><br />Maybe its just because they launch from the desert and don't like the sun on the upperstage for a number of weeks. They seem to be blowing air under the insulation, because that red thing looks like a normal air compressor pump to me<br /><br />

 

[syndroma]

Block DM is LOX/kerosene. The absence of ready-to-fly hydrogen upper stage is one of the problems of Russian LVs. Some people say that it's better to develop LH2/LOX upper stage for Proton than developing new Angara vehicles. Others say that any vehicle which use hydrogen is doomed to be expensive.<br /><br />ProtonM is an upgrade of the ProtonK, it has new digital control system and it can fly only with the Breeze-M. Also, ProtonM launches commercial sattelites to G<b>T</b>O, while ProtonK launches Russian-built sattelites to G<b>S</b>O.

 

[gofer]

(just some general comments) It appears Khrunichev has the technology and has actually cut the metal for an LH upper stage, and assembled some for the Indian GSLVs (e.g http://www.spaceandtech.com/spacedata/elvs/gslv_sum.shtml , and it has flown once or twice with the cryo stage, first in 2001) I realize upper stages for different LV families are somewhat different (diameter, structural loads, interfaces), but it would seem Khrunichev could easily adapt the thing for the Proton-M now, and/or the future Angara. Although, being launched from Baikonour, or even Plesetsk (with the Angara) instead of the Southern India, I guess they'd need to up the energy characteristics of the stage. <br /><br />The shroud with the air-ducts is the air-conditioning system for the payload for the environmental control pre-launch (sharp temperature/humidity changes in Baikounour)<br /><br />It's stacked horizontally, and the only interfaces are on the bottom of the first stage oxidizer tank, so there is no machinery after stacking except the erector train. The pattern on the bottom of the first stage tank is the interface for the fuel lines and ground connection interfaces; works sort of like an electric plug, they erect it, 'plug it in', it launches and unplugs, the umbilicals are pulled underground and covered with armored plates (the MBR heritage of the URM-500), quite a few of their rockets works that way, highly automated stuff (most exemplified by the Zenit)<br /><br />p.s. btw, here's "the user's manual" from ILS for the both Protons -M and -K (11mb) with details on the history and the operation: http://www.ilslaunch.com/missionplanner/pdf/pmpg_r4.pdf (11mb)

 

[syndroma]

Yes, they've built LH upper stage for Indians, they have the technology. But all of their resources are consumed by the Angara and nothing left for cryo stage (called KVRB). When Angara starts flying, you may start to expect the first upgrade - introducing KVRB upper stage instead of Breeze-M.