wb99999999

Members
  • Content count

    32
  • Joined

  • Last visited

Community Reputation

4 Neutral

About wb99999999

  • Rank
    Rocketeer
  1. Hello! I was trying to build an Araine 4 replica and noticed your config used a model from KW rocketry and another model from RSB as the European HM7 series of engines. However, the KW model is hilariously over-sized even after rescaling, having a 5 meter tank butt; the RSB model's size is good, but like all RSB parts, lacks a bottom attachment node. Would is be possible to have a bit of tweak from you guys about this particular config?
  2. It seems to me that your heat load problem sounds a lot like when I played RSS without RO (and thus default thermal settings), but if you got the entire RO bundle this is probably not the case then. Just a reminder that the standard MK1 capsule has a LEO-rated heat shield built-in with RO, and both MK1 and MK2 capsules should survive a low orbit reentry WITH EASE especially if you do a ballistic (non-lifting) reentry: they probably would survive a negative perigee if you have them plunges into the atmosphere steeply and decelerate rapidly. So what I am saying is no, there's definitely something wrong going on with your install. CKAN is unlikely to have a lot to do with it though...
  3. Your case sounds like incorrect/faulty thermal configs on the mods... you may want to check if you have the RO patches correctly installed. Are you using CKAN or did you do a manual install? Did you install Realheat?
  4. I have encountered a very strange issue... I've been messing with procedural SRBs, and it occurred to me that whenever I set the burn time below 2 minutes (120 seconds), the booster bugs and reset the burn time to 2 minute and 14 seconds (and thrust level correspondingly) upon loading the craft on the launch pad. The parts work fine when burn time is set anywhere above 2 minutes, but as soon as I lower it below 2 minute, it bugs out and resets the time. Any clues on how to fix this?
  5. I have checked my install: I am using Filter Extensions, but not anything else; it also happened in sandbox mode. The parts seems just not being configured (since it's 3 sets of parts with normal, cryogenic and service module variant all derived from that 1 set of parts in stock and therefore ven's revamp)
  6. For some reason I was unable to find the RCS/Monoprop version of the Stratus series tanks (The surface attachable ones from VSR and therefore Stock) in the 1.2.2 release. The default version and cryogenic version of the same tank is present, but I really loved the Service module version of these parts, for storing attitude control propellants and also for cheating the pressurization system (if you have even 1 small tank that is highly pressurized and cross-feeding, you can run pressure-fed engines without hauling a heavy service module. These tanks were in the 1.2.2 pre-release and older ROs. Am I the only one having the problem?
  7. Yes! The cooling is much better after the 1.3.1 patch! Now the boil-off literally doesn't happen if I turn the cooling on and give it a little time! Thank you!
  8. Apparently the Proton rocket have some of the highest TWR engine in the world. Its first stage RD-253/275 engine is the second highest TWR in any rocket engine in the world, only beaten by SpaceX's brand new(that is, compared to the Cold War era design used in Proton engines) Merlin engines. The second stage engine, RD-0210, also has a very high TWR of more than 100. From my point of view, these engines are extremely powerful (per mass) and highly reliable, yet relatively simple and inexpensive. I understand that hydrolox engines like the SSME and J-2 can only achieve about 60 to 70 TWR because the complexity involved with the very low density hydrogen fuel and the huge difference in density between LH2 and LOX; however in the Kerolox front, it still took some radical design choices and technological innovations to produce engines of similar TWR, NK-15 and Merlin respectively. I speculate that hypergolic propellant must played a role in this situation. Having your fuel and oxidizer spontaneously combust must simplified a good portion of the machineries in the engine to reduce mass/increase power significantly...but I have no proof for this. Can you guys give me some insight on this?
  9. I see. Still, it is how inoptimised the whole thing is that made me scratch my head.. I mean there're just so many compromises in the design, I'm not even sure the cost reduction and technological readiness is enough to justfy it... This thing is just so counter-intuitive, with a longer burning stage actually having lower Isp but higher fuel fraction and non-separating booster and massive dead weight... the "cost per performance" seems very grim...
  10. Your point exactly. If I'm not getting something horribly wrong, the empty mass of a solid fuel booster would exceed a similarly-sized liquid rocket assembly for quite a bit. A liquid rocket's tank is just a thin layer of usually aluminium or stainless steel, while a solid's casing have to be a lot thicker and heavier to withstand the combustion pressure, acting effectively as the combustion chamber of a liquid fuel engine. I probably played way too much RO and became alien to the idea of Moar Booster, but it is a valid point. ISRO is apparently a tightly budgeted agency...
  11. Hi everyone! I've been reading about the curiously designed ISRO vehicles lately, and here's something that deeply confuse me about the GSLV launchers: The GSLV is a 4 staged rocket (of a sort). It has 3 stages stacked in tandem and 4 strap-on boosters acting as stage 0. The thing that confuses me a great deal is how the 2 starting stages are arranged. It uses a solid S139 booster as the core which does 4.7 MN with 269s Isp, and the four strap-ons are liquid boosters which does 760 kN each with 262s Isp. So far so good for me, even the usage of a solid as the core is a bit odd, but I totally understand the design choice since it has a higher Isp and is adopted directly from PSLV along with the second stage (which justifies using the S139 as the core stage given that they don't need to develop a new interface to mate with the second stage.). However, it is the burn time and staging order that gives me trouble: not only the liquid strap-on boosters DOES NOT separate from the core (still okay for me, the Russian Angara had considered a similar staging choice), it has a whole minute longer burn time than the core. It doesn't make any sense to me. From my understanding, the last bit of fuel in a stage is the "best" fuel, since the fuel are only pushing the higher stage and payload, without pushing on a lot of yet unused fuel. But for this vehicle, the last 60 second of the boosters' fuel is literally pushing an empty, heavy solid rocket casing. If one consider the liquid boosters probably have a higher fuel fraction than the solid core, it comes out even worse. An analog that came to my mind is an Ariane 5 that does not throw away the solid booster after they has burnt out... The point is, judging from the numbers, it seems to me that it is so OVERWHELMINGLY beneficial to at least jettison at least something for the first stage, even at the cost of complexity and some perhaps costly redesign. In my opinion, at this point the staging has gone beyond sub-optimal and entering the realm of counter productivity: the performance that the vehicle will gain from a better staging would be very large and this is exactly what they did for GSLV Mk3. The Mk3 uses a Titan style staging by the way, where strap-on boosters are ignited on the ground, and the core stage is only ignited after the booster separation. So it follows that there has to be some reason that forced ISRO to opt for such a design. Could any of you friendly folks give me some insight on this?
  12. Unfortunately these were not included in the default RO config to start with. Otherwise it would be very easy to copy and paste, even for a dumb person like me...
  13. Would it be possible to get configs for HG-3 or J-2 Sea Level? I know one can always make a config for himself, but I feel like leaving this to the pros especially since these are non-production models and the parameter are to be researched.
  14. Thanks for the advises! In fact, this was exactly what I've been doing with the config: I changed only the type of the plume and nothing else. However, both of my attempt resulted in malfunction, with the first one resulting the two exhaust ports having no plume nor flare whatsoever, and the second one resulting both main nozzle and the exhaust ports having no plume and flare. simply changing the plume type seems to mess with the setup somehow... Also, my point of using Kerolox plume is largely based on the fact that real life RS-68 has an ablative nozzle, which produces a yellowish-red "dirty" plume with carbon and other heavier molecule, instead of a clean, blue water vapor often seen in SSME and the likes. It kinda looks like the Soyuz's plume if you look carefully...
  15. First I have to say that these engine models are BEAUTIFUL!!! Secondly, how does the exhaust port real plume config work on engines like RS-68? I was messing around in the file trying to get this engine run the Kerolox plume for a more realistic aesthetics, but whatever I change seems always break the whole thing and cause the main plume, the exhaust port plume, and sometimes both to malfunction and fails... I understand that there's a bit more in this multi-plume config than the usual real plume ones. Can I get some hint/tips from you guys?