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About sevenperforce

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  1. Running some numbers to see what an Atlas-configured ET-and-SSME-derived launch family would be able to send to orbit. Launch TWR is somewhat of an issue; the RS-25s provide 1,860 kN each at sea level, so five of them would have a max takeoff thrust of 948 tonnes thrust. However, the SLS core masses 967 tonnes not including engines. If the RS-25 had its vacuum thrust at launch, a super-Atlas configuration could put 36 tonnes into LEO. If we up the ante and place six engines on the base (two at the center, four on the skirt), things get a little better. We have 1,138 tonnes thrust to play with, which gives us breathing room. With four engines on the skirt and two on the core, dropping the skirt when just over 87% of the fuel is expended, you could put 39.6 tonnes into a 185x185 km orbit from the Cape. Launch TWR is 1.11:1. Probably not possible to put a second stage on this, but parallel boosters would make it quite impressive.
  2. At least I've still got the altitude record!
  3. That's what I did. EDIT: Ah, I see the problem. i needed to drop the ModuleManager dll into the GameData folder too.
  4. I've always played vanilla, but I wanted to add Tweakscale, so I did. Downloaded the mod, unzipped it, and dropped it into my "GameData" directory. Then I opened KSP, made a new sandbox game, went to the VAB, added a part, right-clicked, and...nothing. I feel stupid. What step am I missing?
  5. Was just thinking... If NASA really is determined to throw their mothballed SSMEs into the Atlantic, there's a particularly efficient way to do it: Super-Atlas. No parallel boosters. Redesign the four-engine thrust platform to make it open; put a fifth RS-25 at the center. All five engines fire at launch, but the thrust platform with the four RS-25s drops away part of the way through the first-stage burn, leaving the center sustainer engine to run through to MECO. An RS-25-based Super Atlas. Then, repeat the exact same arrangement with the RL-10s on the upper stage. This way, the upper stage finishes with just a single engine, meaning it can be its own payload if equipped with the previously-described persistent modular propulsion system components. Or it can fly without those components and merely be used to lift very heavy payloads. I'll run some numbers tomorrow but I think it would be pretty badass. EDIT: Of course, SRBs or Advanced Liquid Boosters could be used optionally. One really nice thing is that the sub-staging point (dropping the engine ring) can be varied based on payload and ascent profile, whereas traditional serial staging is pretty much noncustomizable. EDIT 2: Those familiar with the history of the Saturn program may note the similarity to the S-1D proposal. EDIT 3 (because apparently I cannae stop editing): In theory, an entire launch family (like Atlas V) could be assembled around the same ET-derived hydrolox single-SSME core. You could have a near-SSTO with two auxiliary engines on the thrust ring (a la Atlas D Mercury), a 4+1 variant (a la Saturn S-1D) with or without a second stage, or various parallel-boosted configurations.
  6. Ran some quick numbers. Replacing the SLS boosters with Pyrios boosters (2 x F-1B, 1,054 tonnes gross launch mass each) and using a 145-tonne second stage powered by four RL10s allows you to put 145 tonnes into a 185x185 km orbit matching the inclination of the ISS, launching from Kennedy. This means the "payload" can be the same size and weight as the second stage, so you have common manufacturing between the tank on the upper stage and the tank on the Persistent Modular Propulsion System. The PMPS would then be able to notionally place up to 77 tonnes in lunar orbit, or it could send itself to lunar orbit to act as a propellant depot with 45 tonnes of propellant remaining. Multiple PMPSs would be able to dock to each other lengthwise for propellant transfer or for asparagus-staged transfer burns. With that kind of system, you can literally send ANYTHING to ANYWHERE. Of course, you'd need to devote some funding to actual mission architectures. Establish a lunar base, retrieve an asteroid, head to Mars, that sort of thing.
  7. Inductive ignition is nice but catalytic ignition is faster and more reliable. Though H2O2 is not terribly pleasant to handle.
  8. My preferred SLS replacement: Persistent Modular Propulsion System Stretched ACES-derived hydrolox upper stage with a single powerplant derived from the RL10 and spark-based ignition system Solar-based autogenous coolant system for propellant persistence Hydrolox RCS thrusters for independent orbital maneuvering Side-mounted docking system with magnetic structural linkage and propellant transfer capacity Forward docking system for orbital payload coupling High Energy Upper Stage (similar to EUS) Uses the same tank and engine as the Persistent Modular Propulsion System No thrusters, coolant system, or docking system Additional thrust structure that allows four engines rather than one Core Booster (same as current SLS) Core tank and thrust structure assembled at Michoud Four RS-25s Advanced Liquid Parallel Boosters Pyrios-derived kerolox boosters Two F-1B engines per booster That's all. Launches either send a full PMPS into orbit to couple with a BLEO payload, or they send very large BLEO payload components into orbit for assembly. Contract with commercial providers for smaller payload components and crew launches. Orion is fine, just launch it unmanned on a Delta IV Heavy or something.
  9. I would much rather spend the SLS money on helping to fund commercial lift vehicles and developing BLEO missions and stages. I agree. Though honestly Ares 1 can be dropped altogether. Let the commercial crew program handle man-rating and stick to getting large payloads into orbit for actual missions.
  10. With a bunch of Separatrons, I can boost my acceleration up to 1,270.1 m/s2; with artful use of 4x warp, this will get me to c in about 16.4 hours. Ignore the "max acceleration" shown; that is adding its spin rate, which is rather prodigious at this point.
  11. Here's the LV. Infinite electricity, infinite prop, no heating damage: Toasty on ascent: Even toastier in space. Solar escape was reached within the first 2 minutes. This is after I let it run a bit longer. Looks like the maximum acceleration is 266.3 m/s2, so I'd need to run it for just over 32 days. EDIT: Actually, upon review, an empty Separatron has a far higher TWR than a Mammoth, so lemme rebuild it real quick.
  12. Not sure if it's considered a glitch, but if you DO get enough speed going, you can always get a nice multiplier by smashing into Jool just right. In reality, there is a maximum gravity assist you can get, but I don't think the game simulates slingshots properly at high speeds. The Mammoth has the highest vacuum TWR of any engine now. I used two of them and turned on infinite propellant and infinite electricity -- lemme see how fast I get to c.
  13. You need an effective fuel fraction of 1:1.193e3161. No, that's not a typo. 1.193x103161. That's 11,930 thousand million billion trillion quadrillion quintillion sextillion sextillion septillion octillion nonillion decillion undecillion duodecillion tredecillion quattuordecillion quindecillion centillion centillion centillion centillion centillion centillion centillion centillion centillion times more fuel than payload. Given that the mass of the Dawn ion engine is a quarter-tonne, you'd need 3e3160 metric tonnes of xenon, not counting the mass of the tanks. To put this in perspective, the mass of the observable universe is roughly 6e49 metric tonnes. If every particle in the observable universe was a massless Dawn ion engine that could consume one trillion universes every nanosecond, and you ran these engines from the Big Bang until the heat death of the universe, you would still need to repeat this process 10493 times before you'd burn through that much xenon.
  14. Not really, I don't think. Compared to a modern fighter, a glide-down shuttle has a very limited range of conditions. There's virtually no variation in descent profile; the only variables are weight (in case you're bringing downmass home) and crossrange path. Why would you go for a separate OMS system at all? The only reason the Shuttle used OMS was to avoid having to crossfeed the SSMEs from the ET and from an internal tank. If you're already carrying your tank internally, this advantage goes away. Catalyzed H2O2/RP-1 is a better combo, imho. High TWR, great throttle range, room-temp, decent ISP, etc.; and storable for reasonably long enough. You can even use the peroxide as the restartable ignition system for a kerolox engine (booster or otherwise).
  15. Note -- in testing, aero forces tend to break exposed radiator panels at around 60 m/s at SL. Just for reference.