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Northstar1989

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  1. Awesome! By the way, one thing that may need to be considered (and rarely is in mods) for balance and realism: tech node and unlock cost (that one-time fee you pay to unlock parts with the right difficulty option enabled...) Both should probably be somewhat higher than where I had them before: for gameplay purposes, too many mods cluster parts about where they were (especially in Community Tech Tree), and the unlock cost needs to reflect their high utility... And, for realism I did more reading since setting these parameters in my mod: and it appears that while Mass Drivers l
  2. Impressive! All this, AND those 1.75 meter jet engines we were talking about earlier? (which I BADLY need for the super-heavy airlaunch platform I've been working on for my Career mode games: to lift massive rockets to 24-30 km and then release them for their trip to orbit...) Rad, man!
  3. Don't just automatically assume you know better than another player more experienced than you and post a Craft File: that's just rude. Yours is a grossly suboptimal design: if you're going to use a Mk3 fuselage, it should only be for much larger payloads than that (or MULTIPLE payloads in that weight range). If I were going to lift a payload of that size to orbit, I'd use a long Mk2 fuselage, with 1.875 meter fuel tanks on the payload. This will get you to orbit for much less fuel, as the Mk2 is a Lifting Body and more aerodynamically efficient (in FAR and especially in Stock- which
  4. Comfortable? For optimum efficiency a spaceplane with a Mk3 fuselage requires at least 8-10 jet engines. Any less than that and you're wasting fuel on an excessively-slow ascent and run for speed at altitude. With 1.875 meter supersonic jets, we could do this with just 4 jet engines (each 1.875 meter jet could have 2.25 times the Thrust of a 1.25 meter jet, to get the same Thrust per unit of cross-sectional area: so 4 of these would be equivalent to NINE 1.25 meter jets). This would also generate less Drag- for the same reason four 1.875 meter stacks generate less Drag than nine 1.
  5. A lot more than a comparable rocket (TWR is at least, 1:20 to maybe 1:24, with the mixing chamber ramjets also active). But Effective ISP is much, much higher (in the range of a jet engine just for the ducted rocket performance, 3500-4200 sec Effective ISP, depending on mixing-ratios of LH2:air). This is basically a type of Hybrid airbreathing/rocket engine, much like the SABRE, except that the TWR is actually much better than many jet engines (which typically range from TWR of about 1:6 to 1:12), and the airbreathing Effective ISP a bit lower than some high-end jet engines. The Thrust
  6. Adding mass to the trip is kind of the point. It adds a new aspect to mission planning- taking a longer/slower trajectory and saving fuel, vs..a faster one to save life support mass. It also synergizes well with nifty things like Greenhouses- if they added those too.
  7. Because then you need two seperate, both very heavy, engines. A nuclear ramrocket might be lucky to clear a TWR of 15:1 or maybe 20:1 (with enough bypass, Thrust from the scram/ramjets, more modern materials than NERVA, and a more powerful reactor than NERVA) in atmospheric mode- but at least you don't need a seperate system for vacuum thrust. A chemical ducted rocket gets maybe 30:1 TWR, but then you need an entire NTR for outside the atmosphere that weighs at least as much as the ducted rocket- and probably about 5-6x as much (NTR's only get a TWR of maybe 2:1 at best, NERVA only manag
  8. That applies to pure Nuclear Thermal Rocketry. But this isn't a pure nuclear thermal rocket we are talking. You take the power output of the reactor, and then you divide that among a MUCH larger Working Mass in a nuclear ramrocket- similar to how using heavier propellants gives you higher Thrust from a nuke. But there is no Effective ISP cost to doing this here, as the extra Working Mass cones from the air intakes- so you actually INCREASE the Effective ISP while doing this. The problem I was referring to is that a current-generation nuclear reactor weighs a lot, while not prod
  9. Let's not forget this thread was about nuclear ramrockets? There are plenty of intelligent things to say about that: like I've been considering the TWR, and am concerned it would be abysmal without a much more powerful nuclear reactor (than what is currently possible with US reactor technology). However talking about a TBCC engine (which the US has been working on its own versions of for a decade at least) as propaganda doesn't say anything about the possibilities for nuclear ramrockets.
  10. The publication I linked was not from the Chinese state media. It was from a U.S. Air Force publication, 2 years ago. No corrections have been required to these articles since. These aren't multiple engines they are looking at designing. This is a single, multi-stage engine they are ALREADY building the factory to manufacture. The design work was apparently done years ago, in a highly secretive manner... You would know all this if you read the publication. EDIT: The engine in question (TBCC engine) has already been built and tested on test-stands, as of last year. Next step
  11. P.S. And if you think 3-mode engines are insane, the Chinese recently opened a factory to assemble FOUR mode engines: turbofan, ramjet, scranjet, and (ducted) rocket all in one: https://www.airuniversity.af.edu/CASI/Display/Article/1604494/chinas-opening-a-factory-to-build-engines-for-hypersonic-missiles-and-spaceplan/ What I suggested is actually simpler than this, in that it does away with the turbofan and Scramjet parts entirely (*OR* swaps the Ramjet for a Scramjet) and uses the ducted rocket to achieve ramjet speed (Mach 2) instead.. Only the heat source for the rocket
  12. Actually not. The rocket part of a ramrocket generates Thrust even when stationary. The rocket exhaust ignites the fuel-air mixture in the mixing chamber, so you get some (stationary Thrust from the ramjet part of this mutt of a rocket and a ramjet... (even with the scram-rocket version, the rocket itself will produce Thrust up until you reach the supersonic speeds necessary for the Scramjet part to ignite. And, this can be combined: for instance the proposed RBCC cycle is an all-in-one Ducted Rocket, Ramrocket, and Scramrocket...) The KSP ramjets actually perform much like ramrockets
  13. So, in looking at Air-Augmented ("ducted") rockets recently, and considering nuclear propulsion, this idea came to mind (I think I've read about it before- will post links for background when I have time) Basically, it combines the features of a nuclear thermal rocket (aka. 'NERVA' aa the most famous example) or a nuclear thermal turbojet, with a ramrocket (itself the hybrid of a Ramjet and an Air-Augmented Rocket). So, it looks something like this: air enters into intakes (and probably then a pre-cooler passing some heat to Liquid Hydrogen as a heat-sink: ala. "SABRE" intakes in re
  14. A while ago there was this excellent discussion on air intakes and drag in KSP: This is still an important topic (would be even more so if the dev's could give us some larger airbreathing/jet engines, so spaceplanes are actually useful without massive engine-spam!) and I wanted to continue to draw attention to the idea, discuss it, and see if anything has changed. Also, there were some nuances to Right's graph (re-posted below for convenience) that I don't think really got any proper discussion- and couldn't be discussed there now without nero'ing a very old thread... Note
  15. They are, if you assume 1 EC=1kW. However 1 EC does far, far more than 1 kW could ever do in reality in an ion thruster- and far less than it would do in terms of powering probe cores. For the game scale/balance they're right on the nose, though. KSP-Interstellar has next-gen reactors which are amazingly more efficient for space use, though, and are ALSO true to real-life science. The difference is, the past tried/true tech represented in NearFuture is outdated and EXTREMELY marginal for space use (ironic given the name "NearFUTURE"- it's all nearPAST), whereas Interstellar has the kin
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