Northstar1989

Hi Kishmas, Glad to have you aboard! A key bit of advice- get familiar with the KPS Wiki. It's chock FULL of useful information, tutorials, and advice. A few hours with it was how I taught myself to play KSP, and got to orbit on my first launch. Also, I *highly* recommend installing the MechJeb2 or Kerbal Engineer Redux (KER) mods, and Ferram Aerospace Research (often referred to here on the forums as "FAR"). The former will provide you with rich informational readouts on factors like your Delta-V (how far your rocket can carry you, essentially- although I suggest checking the KSP Wiki for a more complete/complex definition), your Thrust Weight Ratio (TWR) on the launchpad, and your orbital parameters (orbital period, apoapsis/periapsis etc.) without having to switch to the Tracking Station or Map View... Interestingly enough you'll hear MANY, probably MOST players here on the forums throw around the terms TWR and Delta-V, yet strangely some players refuse to play with MechJeb2 or KER, which are the only methods I know of to actually obtain this information in-game without having to sit down with a pencil-and-paper and calculate them by some very convoluted methods (you need to figure out the exact fuel mass of your rocket to do it that way, for instance...) MechJeb2 also comes with some nifty autopilot and flight-assist functions that can make the learning curve for KSP much less steep, when you can rely on the autopilot to do some of the flying for you (trust me, it can't do it all- and some thing you'll quickly discover you can do much better yourself) so you can focus on learning how to build successful rockets and spaceplanes in the first place before tackling trying to become a skilled pilot as well as rocket scientist... As for Ferram Aerospace Research, I *highly* suggest starting off with that mod *As Soon As Possible* because the devs have announced stock KSP is due for an Aerodynamics Overhaul in the next update. FAR is without any contest the BEST (and in fact, to my knowledge, the ONLY) mod that accurately and realistically simulates aerodynamics in KSP at the moment. Installing it will get you in the habit of building realistic rockets now, so that when the stock Aerodynamics Overhaul arrives, you'll be fully-prepared for the more realistic aerodynamics (right now, we have a stock aerodynamics model where you can literally drop a lead ball and a feather *inside the atmosphere* and as long as neither is a wing part, they will fall at the *exact* same rate...) Yes, FAR comes with a lot of informational readouts and displays- but you can effectively ignore those. They just provide you with useful information/statistics on your plane/rocket's design so you can build your rocket/plane to be it's stable BEFORE you launch it. But when you're first starting at KSP, crashing regularly is a ritual of the learning-process every rookie goes through (yes, even me, who made it to orbit on my first launch through a bit of beginner's luck- my 2nd launch crashed and burned miserably, as did my 3rd and 5th...) and half the !FUN! And if you think KSP isn't hard enough, you should really try Dwarf Fortress some time. It's the only game I know of where the unofficial community-motto is "Losing is !FUN!". The extra difficulty in KSP just adds up to extra reward when you finally get it right. Regards, Northstar

Put simply, Fractal_UK said he didn't have time. He was actually interested in adding Nitrogen as an electric and NTR propellant... That's the correct resource- and the one I *STRONGLY* advise using so that it will be compatible with RealFuels... The density is really low because, like you said, it's the gaseous form of Nitrogen. However, this is the form that would probably be used in real life, as it is what the Helicon Double Layer Thruster is designed around (working models have been tested on the ground), and the basis of all Nitrogen-RCS (which RealFuels already adds). The density problem is a non-issue as RealFuels assumes tank compression of 200x (leading to an effective 20,000% utilization). You should do the same. Simply figure out the appropriate volume for a fuel tank (in liters), and multiply that number by 200 to get the appropriate Nitrogen-capacity. This is actually a low-end figure for Nitrogen compression, anyways. Some quick calculations using an online Thermodynamics calculator showed that it is EASILY possible to get as much as 800x effective compression by pressurizing to 200 atmospheres (not an unrealistic pressure level for a service module tank- it's similar to what we use for breathing Oxygen) and then cooling it to -125 degrees Celcius (by comparison, Liquid Nitrogen has to be stored at a maximum temperature of -196 degrees Celcius). Sure it's still a fairly low density for a fuel resource, but it *does* help to counteract the other problem you mentioned... ("One Resource to Rule Them All") If LH2 is getting 8093 m/s, the Nitrogen should only be getting 2171 m/s at that temperature (based on the relative molecular masses). Of course, maybe the reactor has a slightly greater efficiency when utilizing Nitrogen for some reason (but KSP-I assumes 100% efficiency for thermal rockets, so I'd still go off the relative exhaust velocities I just mentioned). Lower ISP means higher thrust, however. I'd suggest utilizing the relative ISP values I e-mailed you, which were calculated based on the relative molecular masses of H2 and N2 (another theory- the source you found may have assumed a *higher* exhaust temperature for Nitrogen as its boiling point is higher when stored as a cryogenic liquid, and is stored even warmer as a gas- however KSP-I doesn't normally model such effects in the ISP values...) That value for ISP is still a little too high (and also leads to too low of a thrust as a result). Honestly, high-thrust low-ISP fuels are more !FUN! anyways as you end up with a bigger, faster rocker... Go for it! The ability to manufacture Ammonia outside the atmosphere of a planet is one of the *most important* reasons to add Nitrogen as a resource (Propulsive Fluid Accumulators are the other). You're talking theoreticals here, but have you ever actually TRIED building a Propulsive Fluid Accumulator? (hint, I have, and it's the *exact* strategy you're describing, although real life proposals use specialized satellites whose only job is to collect the Nitrogen for greater efficiency...) It's *NOT*, I repeat *NOT* easy! PFA's are most efficient in circular (NOT elliptical) orbits in the uppermost atmosphere (above 60 km in stock), but it takes FOREVER to accumulate a significant amount of fuel at that altitude. And if you dip too low, drag QUICKLY starts pulling you down towards the planet faster than you can possibly counteract it with Nitrogen gathered from the atmosphere... It's a *VERY* fine line you have to walk to build a successful Propulsive Fluid Accumulator. Players can and should be rewarded *greatly* for succeeding in this endeavor- especially as it's an example of a REAL proposal for ISRU that has actually been on the books for quite a few decades now here on Earth... (since the 1960's, and I must emphasize NEVER did *any* Propulsive Fluid Accumulator proposals suggest using thermal rather than electric nitrogen-propulsion...) KSP-Interstellar never shied away from real-life technologies just because they seemed overpowered (Alcubierre Warp Drives, on which the mod was founded, are a prominent example), and neither should it now. Oh, and by the way, if players utilize this strategy with RealFuels installed (if you take my advice and use the same resource stats as RealFuels to ensure compatibility), they will also have to deal with mitigating boil-off of the collected Nitrogen (though not nearly as bad as for storing Liquid Hydrogen)- which is another issue that adds difficulties to Propulsive Fluid Accumulator strategies... I hate to pressure you, but I'm going to have to pressure you here. Propulsive Fluid Accumulators are *NOT*, I repeat *NOT* worthwhile without access to Nitrogen-electric propulsion. In fact, I'm not sure if it's even POSSIBLE to build a system that collects a greater mass of Nitrogen than it expends counteracting drag without it (so long as the Atmospheric Scoops only work inside the atmosphere, instead of just above the edge of it- an issue I have been bugging Fractal_UK to fix, since REAL atmospheric scoop proposals all involve scooping at 120-200 km: ABOVE the 100 km Karman Line...) Helicon Double Layer Thrusters are a real-life technology that has already been *proven* to work (see the article I sent you by PM, which details numerous ground-tests of Helicon Double Layer Thrusters using Nitrogen as a propellant), and Propulsive Fluid Accumulators (the real-life strategy I want to replicate in KSP-I) are not feasible in real life (or KSP with any of the Real Solar System re-scales) without Nitrogen-electric propulsion... KSP-Interstellar has, once again, never shied away from a real technology because it seems "OP'd" (may I mention that *EXACTLY* the same criticisms could be leveled against Munar ice-mining, i.e. that it allows indefinite operations outside Kerbin?), and there's no reason to start now. One last thought on this- Helicon Double Layer Thrusters are a type of plasma thruster, but there are indeed several different types. The KSP-Interstellar plasma thruster already models *several* different real-life plasma thrusters in one part, though, as no single real-life plasma thruster design is actually able to operate on all of the different electrical fuel types already in the mod. Could you please, please, PLEASE add Nitrogen as an electrical propellant? The whole point of my request was to get the coding work done for Fractal_UK so he could add Nitrogen as a resource and allow players to create their own Propulsive fluid Accumulators. This simply isn't possible (or if so, is VERY marginal- and doesn't work AT ALL for Real Solar System players such as myself- I play with the Kerbin 6.4x re-scale...) without Nitrogen-electric propulsion. The strategy of Propulsive Fluid Accumulators is essentially no more nor no less OP'd than any of the other ISRU strategies requiring ZERO input resources- such as ice mining on the Mun- and there's no reason to give this one special treatment. In fact, PFA's are *SIGNIFICANTLY* harder than Munar ice-mining, as on the Mun you can just land a really big nuclear reactor to power your ISRU plant and run it at 1000x time-warp if necessary... With PFA's, it's a *requirement* to set up a Microwave Beamed Power infrastructure or utilize some reactor with greater power-density for volume than basic fission (Fusion or Antimatter Reactors, for instance. Even Antimatter Initiated Reactors won't cut it, as they actually have a low ratio of volume, and thus induced drag in FAR, to power output- and instead opt for a lower reactor mass than fission, which doesn't help *at all* with the economics of PFA's when using FAR: where drag-power ratios are all that matter, and the mass of the satellite is completely irrelevant...), and PFA's can *only* be used at physical (up to 4x) time-warp, so Propulsive Fluid Accumulators are actually MUCH harder to set up than Munar ice-mining... Regards, Northstar P.S. There's *another* MAJOR reason for utilizing nitrogen-electric propulsion for Propulsive Fluid Accumulators besides the ISP, by the way- one that you seem to actually have noticed in your discussion of thermal thruster degradation. As you'll notice in the PDF link I e-mailed you, Helicon Double Layer thrusters are not a design that allows for grid-erosion (the factor normally limiting electric propulsion engine lifespan), and have a virtually *unlimited* lifespan of use in space. The electronic systems on the craft they're attached to are likely to break down due to radiation-exposure (even if *heavily* rad-hardened) far before the Helicon Double Layer thruster, in fact... - - - Updated - - - Please, please, please tell me you'll go back and replace that with "Nitrogen" with the values used in RealFuels in the next revision. The *LAST* thing KSP needs in more redundant resources, where 2 mods have different, incompatible names/densities for the same resource. And since this KSP-I extension has been out such a short time, now is the time to go back and fix that before people start building saves around the old resource name/density. By the way, there's another benefit to ensuring RealFuels compatibility by using the same resource name/density (once again, you can just increase the tank capacities for Nitrogen to make up for the reduced density- Nitrogen gas is highly compressible, and 100 units of a resource at 1/100th the density are identical to 1 unit of a resource at 100x the density of the less dense version, from a player/performance standpoint. But utilizing the same resource name/density makes cross-mod compatibility possible without behind the scenes without patches...) RealFuels already allows use of Nitrogen as an RCS propellant. So if you fix the resource name/density for Nitrogen, and players utilize both the KSP-I extension and RealFuels, they'll be able to scoop RCS propellant from Kerbin's upper atmosphere rather than having to travel all the way to Eve/Laythe to collect/manufacture Ammonia to make Monopropellant... (aka. "Hydrazine" in Real Fuels) Regards, Northstar

This was an SSTO that I launched back in the golden days of my KSP-playing (now, my laptop can barely handle the game) For scale, the central fuel tank to the right is 3.75 meters in diameter (the larger fuel tank was made with StretchyTanks). Regards, Northstar

Hi Boris, I was wondering if you had enough programming/modding expertise to attempt implementing a feature that FractalUK already expressed an interest in adding to KSP Interstellar, but said he regrettably did not have time to code in himself. I was hoping you could then send a Pull Request to get it in the main mod when FractalUK has KSP Interstelalr back up-to-date for 0.90 The feature I was hoping you could add was the use of Nitrogen as an ISRU and fuel resource. Basically, Nitrogen should be harvestable with an Atmospheric Scoop on Kerbin, Laythe, and Eve (corresponding to the relatively high nitrogen contents on Earth, Titan, and Venus, respectively... 78.084%, 98.4% of the stratosphere and upper atmosphere, and 3.5% respectively) using the existing ISRU system. Nitrogen should then be usable as a plasma thruster fuel (corresponding to the real life Helicon Double Layer plasma thruster) and as a thermal rocket fuel (thermal rockets can run off basically any non-corrosive gas). FractalUK already expressed interest in coding both of these into the KSP Interstellar mod- but implied he didn't have the time for it. He also said he didn't have a good model to use for a fuel tank part that could hold nitrogen (the linked post discusses the issues with tankage). The last of these issues (the fuel tank) could be filled as a stopgap measure by re-using the textures for one of the stock fuel tanks. Or, alternatively, you could implement a tweakable fuel tank the players could *choose* what to fill it with- much like the current tweakable fuel tanks in the Firespitter, B9 Aerospace, Modular Fuel Tanks, and Real Fuels mods... I'm sure FractalUK would be *highly* appreciative if somebody could do a quality job coding up such a long-term solution (a tweakable tank) for an increasing number of resources he wants to simulate... As a side-note, the RealFuels mod already has accurate parameters for its Nitrogen resource (called "N2" in the resources .CFG). KSP-Insterstellar has already shown a commitment to including some realism with things like water electrolysis producing an accurate mass-ratio of Hydrogen ("Liquidfuel") to Oxygen ("Oxidizer") despite the fact that they currently *burn* in an inaccurate 10:11 ratio in the stock game; and with realistic ISRU possibilities instead of a single "magic" ISRU resource like in Karbonite or Kethane... As such, it seems appropriate to utilize realistic density values for Nitrogen- which RealFuels mod conveniently already makes available (as one of the creators of a KSP-Interstellar/RealFuels integration config, I also have a vested interest in seeing both mods use the same resource definitions for Nitrogen- it makes ensuring mod cross-compatibility *MUCH* easier...) This also helps when using the Procedural Parts mod to create custom size Nitrogen tanks- as Procedural Parts already has definitions included for resource capacities for RealFuels-density Nitrogen (as a gas, Nitrogen is actually compressible into a much smaller volume- which is already accurately reflected in the increased Nitrogen capacities of Procedural Parts Service Modules...) Regards, Northstar P.S. The ability to use Nitrogen in a plasma thruster makes Propulsive Fluid Accumulator satellites possible and *profitable* in KSP Interstellar, as the mod already includes the necessary nuclear reactors or Microwave Beamed Power networks (I've actually already built Propulsive Fluid Accumulator satellites before to scoop Oxidizer in KSP-I, but the low ISP of LFO-burning engines ensures that it is impossible to scoop enough Oxidizer to replace the fuel mass you expend counteracting drag... It *is* possible to build profitable designs when running RealFuels, as LH2 and LOX burn in a 1:8 mass-ratio, but then you have to worry about LH2 boil-off, and still have to send up regular fuel-tankers with LH2- *not* an issue with nitrogen propellant...)

Radar, Barry, Nathan- whoever is maintaining this mod now, and notices what I have to say- I have another suggestion. In keeping with the concept of Big Dumb Boosters, I suggest that Procedural Parts mod allow players to tweak the mass of a part *upwards* (but now down) from the normal specifications, in exchange for greatly-reduced cost. This does *NOT* represent the lower cost of weaker/heavier materials, which would not really be that significant in itself, but rather, the use of wider engineering margins in the rocket design. I.e. maybe the part varies +/- 10% in mass and strength, but is simply made 20% heavier for otherwise identical performance, to reflect that you have to design around the full range of possible strengths/masses when allowing greater variability (your part has to be designed at least 10% stronger with a 10% variance to prevent ending up with a part that is too weak- but the entire rocket also has to be powerful enough to still make orbit if the part is as much as 10% heavier/stronger than designed...) With lower precision, you can make use of much lower-tech factories and cheaper machining, and costs come DRAMATICALLY down (my recent experience working to help renovate a precision-manufacturing factory only made me more acutely aware of the cost of high precision). You also get more competition, as more companies have the capabilities to make the desired equipment... All in all, precision is a VERY important economic factor in real life, and the concept behind Big Dumb Boosters really does work.. (The Catch-22 is that because you need a larger rocket to launch the same payload, and multi-part assembly/tugs and/or refueling still aren't widely-practiced in real life- although they have been successfully demonstrated- you need a much better Launchpad to accommodate a larger rocket, which is expensive. Thus was born the sea-launch for Big Dumb Boosters, to get around this problem. But the facilities-cost of building larger rockets is already simulated in KSP's Career Mode, so I don't think we need to do anything more to account for this if we add mass-variability in Procedural Parts...) Regards, Northstar P.S. The Wikipedia article on Big Dumb Boosters pays too much attention to the benefits of mass-production. It assumes that because Big Dumb Boosters would have lower payload-fractions, you would simply build more of them. This is one approach, that was taken by some Big Dumb Booster proponents. But the "true" Big Dumb Booster is, by its very name, simply much larger than a "smart" rocket to obtain the same payload-capacity. For an example of this, see the Sea Dragon- which was meant as a cheaper alternative Mars rocket- but could actually launch more than 4 times the payload of the Saturn V for anywhere from a quarter to twice the cost...

In KSP, SRB-based lifters are much cheaper than liquid rockets, but still not nearly as cheap as a Space-X style launch using liquid rockets. There is no way to built rockets to looser engineering standards, and accept the necessary hit in payload fraction that entails, opting for just building it bigger instead (which is the entire principle behind a Big Dumb Booster- i.e. that a rocket with 1/3rd the payload-fraction due to looser engineering standards might cost a lot less than 3 times a much per ton of rocket0 and can thus be built bigger/heavier instead...) What I'd REALLY like to see is a realistic and tweakable relationship between part mass and cost in Procedural Parts mod (so I can use much heavier parts with much lower cost to approximate the Big Dumb Booster concept...) Regards, Northstar P.S. The parts in a Big Dumb Booster aren't *necessarily* heavier in real life- but instead are built to a much wider tolerance of masses and strengths. If a part could be as much as +/- 10% the designed strength, then you need to design it with 10% extra strength in case it ends up on the weaker end, for instance. With the Rocket Equation, even such small extra tolerances rapidly add up into greatly-diminished payload-fraction (but at the benefit of much lower cost-per-kg). Alternatively, you can go the way of Aquarius and combine the extra mass/strength variance with slim engineering margins for a high failure rate overall (as much as 1 in 3 for the Aquarius rocket). But that's not really a Big Dumb Booster in the truest sense of the word- as it is not necessarily any larger than a comparable-capacity "Smart Booster", only dumber to bring down costs...

Get Kerbal Join Reinforcement (made by Ferram4, the same excellent modder who makes FAR and Better Buoyancy). It's tiered physics-loading will prevent random spacecraft explosions due to phantom forces most of the time... Regards, Northstar

Thanks for all the advice. I'm glad this ended up as more of an open forum for discussion rather than just giving advice to me. For what it's worth, I do TONS of interesting things (at least I think they're interesting- which is what matters). I exercise regularly (I have to- I'm currently applying to the Marine Corps), and I've had many girls tell me I'm "charming"... (15 years of trying to flirt helps- I started in earnest when I was a precocious 10 year-old) Yet NONE of them seem interested in me as a potential boyfriend, or even a date. Even when one shows a little interest, the inevitable end is them out of the blue saying "sorry, I just don't think we're compatible" and refusing to give any more information... Maybe they're right- but I would LIKE a little more explanation than that... Regards, Northstar P.S. For anyone looking to learn a little more about me, for perspective, here's my OKCupid profile. You'll have to create an account to view it, though, but you can always delete it afterwards... www.okcupid.com/profile/Northstar1989

Glad to have you aboard Jack! Feel free to swing over to the Suggestions & Development sub-forum if you want to discuss ideas for the game, see what other players are suggesting, or get a better idea of what's next (some ideas have been labeled as planned for the final game on the stickied threads there) Regards, Northstar

You're talking about stock aerodynamics- a system where a feather and a bowling ball will literally hit the ground at the *exact* same time if dropped from *any* altitude (drag is directly proportional to mass in stock aero). Where biplane wings produce *exactly* twice the lift and drag of single-wings because wings have no interactions with each other. Where breaking the sound barrier has no meaning, and swept wings are useless. It's a TERRIBLE, TERRIBLE, unintuitive system, and you shouldn't expect any behavior from it to correspond to real life. Use FAR instead. Regards, Northstar

Nice- but I don't understand. WHY do people keep using the Rockomax Jubo-64 fuel tanks as Shuttle External Fuel Tanks? Is it because they're orange? Because a LOT of other fuel tanks are orange in real life- such as the fuel tanks of the Delta IV rocket, which is clearly what they're modeled after (both in shape and relative size- the Rockomax-64 is meant for medium lifters NOT, Shuttle EFT's- which should be MUCH larger...) The Rockomax-64 fuel tanks are far too small for a Shuttle External Fuel Tank. You're better off using an SLS-sized fuel tank. Or better yet, a Procedural Parts fuel tank stretched to an even greater diameter... (the Shuttle EFT was 8.4 meters in diameter- which would equate to about 5 meters in Kerbal scale, which is generally about 50% sized...) http://en.wikipedia.org/wiki/Space_Shuttle_external_tank Regards, Northstar

I thought this might be very appropriate, since many KSP players are highly intelligent, and some are probably a little awkward in real life. What dating advice can you offer to other KSP'ers that specifically helps to work around the coolness-factor? (or rather, others' perceived lack thereof- even if we all agree nerds are cool/awesome!) How did you find your significant other? Would your suggest dating other nerds, or trying to date somebody very different? Answer all these questions and more here! Almost anything goes- I would just ask that you clarify whether your advice is for men trying to date women, women trying to date men, men trying to date men, women trying to date women, etc. Regards, Northstar

Actually, part of the problem *IS* that the wings don't produce enough lift, at least in the stock game anyways. To get more realistic (higher) lift values, I strongly suggest you play with FAR... :chuckle: You've never heard of Procedural Wings/Dynamics mod? (it goes by either name) THAT is the only real solution to lifting a Mk3 fuselage. Just add a single wing part to each side, enlarge it to HUGE proportions, and add some control surfaces (and vertical stabilizers). Weld the Mk3 fuselage parts if you really want- but as stated FAR seems to have some issues with welded parts, and you can easily get a <120 part SSTO with a Mk3 fuselage if you just use the Procedural Wings mod... - - - Updated - - - 35 degrees is NOT a typical AoA for a plane (are you sure you don't mean angle of ascent? AoA is defined relative to your prograde vector, NOT the horizon, and you can easily achieve 35 degrees with a high climb-rate..)- *ESPECIALLY* using FAR. And there are MULTIPLE solutions to bring it down: (1) Increase thrust to increase velocity. In stock, lift only increases linearly with speed (which is why I and the devs agree the wings produce too little lift), but in real life and FAR lift increases exponentially with speed. (2) Decrease drag to increase velocity. In FAR, this means designing the wings to have a higher sweep and making sure there are no protruding objects (such as radial batteries) that disrupt the airflow. In stock aerodynamics (which STINK), well tough luck- even cargo bays don't serve any purpose (much like nosecones), as they actually INCREASE drag with the silly linear mass-drag relationship (you're better off mounting a payload on top of the plane with a radial decoupler and struts in stock...) (3) Reduce wingload by decreasing mass. Any extra mass on the plane you don't need will increase the force of gravity, and require a higher AoA to produce enough lift to stay airborne at a given altitude/speed. Extra mass also decreases your TWR, although with a plane (in FAR) this is less of a problem as you will simply accelerate until drag and thrust balance each other (assuming the extra mass doesn't increase drag- say it's inside a cargo bay). In stock, reducing mass is actually even MORE important, as there is a silly/stupid linear relationship between mass and drag (a full fuel tank experiences more drag than an empty one, for instance...) (4) Reduce wingload by increasing wing area. Simply adding more wings will allow you to produce the necessary lift with a lower AoA. Although extra wing area will increase your drag at a given Angle of Attack, it will allow you to fly at a lower AoA in the first place, and thus can actually REDUCE drag in level flight when you're already pushing very high AoA values just to stay airborne... Peak Lift/Drag ratio usually occurs as a MUCH lower AoA than peak lift- around 6-10 degrees instead of 16-24... You also need less airspeed to produce the same amount of lift with more wing area, so you can get away with more drag... I hope all this helps. Regards, Northstar

You should probably reduce the deflection of the spoilers. The greater their deflection, the more they will destabilize the plane. You can reduce flap/spoiler deflection in the SPH with tweakables... Alternatively, just try placing the spoilers further back (which will reduce their effect, but also destabilize the plane less). Personally, I recommend the reduced deflection if you're having difficulties landing, though... Not unless this was changed in a very recent version of FAR (it's been a little while since I used flaps, due to the 0.90 part-count restrictions). Flaps can still be assigned pitch-control functions in the SPH. If their flap/spoiler deflection setting is less than the control-range, they can still be differentially actuated to act as aerlions as well (both flaps and spoilers are sometimes differentially actuated to provide roll-control in real life, so it's NOT unrealistic...) or deflected even further to provide some limited pitch-control (and possibly yaw-control if at an inclined angle). What setting a control surface as a flap does is provide a *minimum* deflection that the control surface deflects to, that you can't go below. Whether you can actuate the control surface further depends on the relative values of the control-surface-deflection for pitch/control/yaw vs. the flap/spoiler deflection settings... You *CAN* reverse thrust it in-flight with Firespitter engines (propellers, and certain B9 jets that use Firespitter code). You can do it manually (by right-clicking) if it's a centrally-mounted propeller (I wouldn't recommend doing this for an outboard engine unless you have thrust set very low, in which case it can be used to cause your plane to turn more quickly. Otherwise you sill probably go into a flat spin...) or with Action Groups set to reverse outboard propellers in symmetric groups... (or asymmetric groups if you want to crash) Regards, Northstar

That's incorrect. The SSME did NOT use Full Flow Stage Combustion- just Staged Combustion (which, although this is *not* the proper name for it, you might call "Partial Flow Staged Combustion"), although they *were* the best-performing Staged Combustion engines ever built until that point. See the Wikipedia article on Staged Combustion for more explanation. Full Flow Staged Combustion is a more advanced variant of Staged Combustion that has never been used beyond the test stand before. http://en.wikipedia.org/wiki/Staged_combustion_cycle#Full-flow_staged_combustion_cycle FFSC has *numerous* advantages over regular Staged Combustion, including lower operating mechanical stresses (allow for EITHER greater engine longevity/reusability OR better performance by increasing chamber pressures or decreasing engine mass), greater safety (it eliminates some key parts that can fail), and lower turbopump operating temperatures Regards, Northstar

Hey guys- you've heard of Full Flow Stage Combustion, right? You know, the cycle that will be utilized on the new Space-X Raptor Meth/LOX engines? THAT is a major advance in engine design (although to be fair, FFSC has been used several times before in engines that never made it off the test stand as funding was pulled on their intended launch vehicles...) Still, the biggest advance in rocketry will be when we stop carrying all the energy necessary for the mission onboard the rocket. I.e. through Microwave Beamed Power... (which is also nice because you can use the same system for deep-space propulsion by high-powered ion engines relying on beamed power..) Regards, Northstar

This sounds interesting, but I think you should take a different approach. How about instead of making this only open to a single team, you allow several competing teams? And what about creating multiple categories (i.e. one for modded games, one for normal KSP, etc.) Just getting anything on Tylo is challenge enough- but there's no reason you can't add a little competition to the mix. Personally, I only play with modded KSP at this point (you won't catch me dead without FAR and RealFuels, and I use Procedural Parts to get around the need to ahve a million memory-hogging fuel tank parts in my catalog). But if there were a modded category, I would be quite interested in taking the role of a Mission Planner or Launch Vehicle Engineer... Regards, Northstar

My complements GregroxMun! I'm glad to see more Kerbin system rescales out there. Now if only Squad would catch the hint and scale the stock system up a bit... I have to point out that this re-scale is actually the MOST accurate in terms of the relationship of part sizes to the planet. That the "stock parts are 64% real scale" is a myth that was first created by Regex, and unfortunately, perpetuated by a few unwitting dupes such as myself (in fact, I probably did more to spread this misinformation than any other person...) The TRUTH is that stock parts are actually only about 40-50% the size of their real world counterparts in most cases. Take the Jumbo-64 tank, for instance, which is clearly an analog of the Delta IV cryogenic fuel tank... The real one is exactly 5 meters in diameter, as compared to KSP's 2.5 meter tank. And a 6.4x re-scale would NOT amount to 64% of real world scale anyways- as the stock Kerbin system is actually slightly closer to 1/11th than 1/10th of real world scale (using the 12,742 km diameter of Earth vs. 1200 km diameter of stock Kerbin...) So, a 6.4x re-scale is closer to 60% re-scale, and the proper re-scale is about 40-50% (which a 5x re-scale falls in the range of). Now if only you woulds get rid of Dres' ridiculous rotational velocity, and return it to a more sensible stock-like value, I would GLADLY make the switch over to your 5x config from 64K... Regards, Northstar

Greetings fellow Kerbonauts! I hope your rockets are flying straight and your spaceplanes are gliding smoothly today. It's a pleasure to be a part of your team (I went and announced I'm joining on over in the Cubesat-specific forum as well). I come to you all with a VERY IMPORTANT ANNOUNCEMENT! For the past few days, I have been working a short-term job to help clean up and restore a precision-engineering factory in Illinois that has been out of commission for the past 9 months. The restoration work is proceeding smoothly, the machinery is in good condition, and the factory will be fully operational within a week. Today I was speaking to my boss (the new owner of the precision-engineering factory), and I mentioned the Cubesat project to him. He got interested in engineering in the first place because of the Apollo Program, and he was very interested in what I had to say. The factory is also looking for a few early projects to cut their teeth and get back in the game of making scientific and engineering apparatus... The good news is this- he thinks the project sounds interesting, and some or all of the satellite components may be within his factory's capabilities. He even remained interested when I told him that the KSP Community Cubesat team may not be able to afford to pay market price for the manufacture of most/all of the components... This is GREAT news! The KSP Community Cubesat project may be able to realize its dream of placing a tiny satellite in LEO after all! I may be able to help us secure precision-engineering of the necessary components at a discount price, as my boss understands that the KSP Community Cubesat Project isn't exactly rich... Here is where you guys come in! We need to design the components and raise the funds for the project in the next couple months. It's achievable- after all, I'm sure you guys know what a small group of dedicated individuals can accomplish if they put their mind to it... Money is needed most of all, of course, or nothing will happen... In this regard, the discount-price manufacturing/engineering may be *EXTREMELY* helpful. But we also need to get the designs for the Cubesat drawn up, so I can get them to my boss and he can decide what is within the factory's capabilities, what's the lowest price he can charge, and what design improvements can easily be made, if any (the factory specializes in scientific and high-tech precision devices, so things like space-grade gyroscopes and reaction wheels should be *right* up its alley...) I should repeat that there *IS* a timeline to this. My boss thinks the best time for the factory to do something like this would be in 1-2 months from now, when everything will be set up and settled in smoothly, but business hasn't really picked up for the factory yet... Thus, there is a HUGE imperative for you guys to pitch in and get the project running quickly, before this amazing opportunity passes! Let's get this thing going! Regards, Northstar P.S. While I would be more than happy to act as a liaison with my current boss, who I also know through my church and is helping me find a more permanent job in the area in the long run (my specialty is NOT precision-engineering, I'm just helping clean the place up and organize it), I would also like to put you guys directly in touch with him eventually. First, we need to select some kind of project leaders, though, so he has somebody concrete to talk to. I would be more than willing to volunteer to be ONE of these individuals, provided you all understand I have no actual background in engineering (I'm a biologist by trade) beyond KSP, and we should probably have at least one or two additional team/project leaders with more experience in engineering fields involved. P.P.S. Feel free to PM me about my volunteering to take on a role as a Project/Team Leader of some sort... I have a STRONG science background (B.S. at Cornell University, M.S. University of Illinois), leadership experience (former Army ROTC and Eagle Scout), a personal connection to the owner of the factory who would be doing some or all of our manufacturing if you guys follow up on this awesome opportunity, and PLENTY of time on my hands- as I am currently only employed with a series of short-term jobs never lasting more than a couple weeks at a time... - - - Updated - - - Oh, and ONE LAST THING. My boss said he would need the preliminary designs in something called "Solidworks" when we're ready. It sounds like you guys already know what that is, as I've seen some discussion of it here on this thread... Just an FYI... Regards, Northstar

The mod may or may not still be working in 0.90 with the files released. My latest test didn't work correctly- will be attempting to fix in the next week or so. Re-compiling for 0.90 may be the way to go- but I've never really compiled anything before. Would anyone like to provide some pointers on how to do so, or help maintain this mod with me? EDIT: The mod contains no .DLL files, so there is nothing that should need re-compiling. I don't know what the problem with the mod is yet, although I am trying to find out... Anyone who has greater expertise than myself (basically, any expertise at all) with modding KSP should take a look at this, and see if they can't give me a hand! EDIT #2: This mod contains no .DLL files, but it SHOULD contain a single .DLL file I missed before (its name led me to believe it was referring to the Science Experiments from the Stanford Torus mod- but it turns out it *ALSO* has code for the Mass Accelerators). I'll see if that fixes the mod for 0.90. If not, I'll need to re-compile the .DLL for 0.90. This is a bit beyond my capabilities, so I would appreciate some help with this. Regards, Northstar

That author's a bit of a prick- broadly dismissing all technological progress (VASIMR, for example, which we now have a WORKING prototype of on the ISS, he states would take "decades and billions of dollars"- which laughably, I assume he actually thinks is a lot of time/money in space-exploration terms...) and mocking those who support such ideas. He's right people get a little carried away with things like Commercial-only Space and NASA-reorganization (and because I understand the relevant issues, I've never been a huge fan of either...) But he's WAY off-base when it comes to technology, and doesn't actually make any legitimate arguments to prove his point rather than a bit of hearsay about what *he* thinks the real engineers are struggling with in regards to a Mars sample-return mission... The ideas proposed in this thread are a very specific set of technologies to solve a very specific problem. Namely, the high launch-cost of getting anything to Low Earth Orbit (the first step to ANY other mission.) Now, don't get me wrong- I never said there aren't PLENTY of other technological and engineering challenges to space exploration and utilization. But the main reason we haven't solved them is due to lack of government financial support to do so... If launch costs were lower, total mission costs would take a sharp hit as well (not only do launch costs make up a significant portion of mission costs- high launch costs also force enormous increases to design costs for things such as scientific instrumentation, as the necessary tools/components have to be built to be VERY lightweight...) Now, back to the topic of this thread. What do *YOU* think are valid technological approaches to reducing launch costs? (I'll be the first to admit- there are a lot of non-technological solutions as well that are simply based on changing HOW you think about launch vehicles or manage space agencies- the Big Dumb Booster approach, or the Aquarius low-realiability approach for launching fuel and consumables, for instance. But discussing those as well is beyond the scope of this thread- which is intended as a focused discussion specifically on technological solutions that don't require major scientific breakthroughs...) Regards, Northstar P.S. Some posters have criticized the solutions here as being futuristic rather than possible with current technology because they don't understand an important distinction: that between precision/finesse of execution and political barriers, and solutions requiring technological breakthroughs... A "skyhook" doesn't require us to invent new materials or make breakthroughs in nuclear physics, for instance, but it DOES require *incredible* precision in suborbital rendezvous (between the lower end of the tether and the suborbital spacecraft), and as such may not actually ever be realized. Microwave Beamed Power doesn't require *any* scientific breakthroughs (we already have developed the necessary microwave-transmitters for industrial/metallurgical uses, for instance), but it DOES require political approval to shoot hundreds or thousands of Megawatts of long-wavelength microwaves through the air (which due to their wavelength, WON'T actually pose a significant health threat to human beings nearby- although they could fry the semiconductors on passenger airplanes crossing their path, as silicon chips *are* significantly absorbant to these wavelengths, unlike organic matter...) at an ascending rocket or spaceplane- and thus may never see realization due to overblown public fears of radiation (this is *exactly* the same as fear of cellphones causing cancer, actually- the relevant wavelengths are far too long to ionize your DNA...) There is a difference between what is POSSIBLE with today's technology, and that which government officials (who don't even all understand how the Internet works) will actually fund...

Unfortunately, not really. Your speed at a given altitude varies, among other things, based on your ascent profile (i.e. how early and sharply do you start pitching over; when do you stage, etc.) You're best off trying to fulfill as many contracts as possible with planes since it's easier to predict speed at a given altitude with a plane once you become sufficiently experienced with them, and very easy to throttle down or go into a dive to increase/decrease speed at a given altitude. Regards, Northstar

You're overstepping your bounds. I was *NOT* wrong about tank pressurization being commonly utilized in space programs (mainly to ease the load on turbopumps, or eliminate them altogether- as with pressure-fed rocket engines- both of which strategies have seen real use in space). Or about LH2 being compressible. What I was wrong about was the DEGREE of compressibility- it appears very high pressurizations only yield a tiny increase in density (Raydar was close- you only get about 12-15% compression at 150 atm with a MASSIVE mass penalty of *150 times* the tank mass...) Nonetheless, real service modules are sometimes pressurized at 30-40 atmospheres if they're feeding pressure-fed rocket engines... This leads to a very small (5-6%) increase in LH2 density- not worth the extra fuel tank mass, and not worth simulating in RealFuels- where you can already out-perform real tanks by achieving utilization of 100% with Procedural Parts mod (remember, the space shuttle EFT was only 94%, and is one of the highest known utilizations...) All being said, a pressure-fed rocket engine requires a pressurized fuel tank. There are mass-savings on turbopumps, etc., vs. a pump-fed design, but according to THIS document, the mass-costs of heavier fuel tanks only make pressure-fed engines lighter for total burn-times less than 1 minute (in practice, that means they're only lighter for an OMS designed to boost a spacecraft into a slightly higher orbit). The *real* reason to use a pressure-fed rocket is that it's simpler, cheaper, and easier to design... (which is why they see extensive use in every Big Dumb Booster proposal) Regards, Northstar

Welcome aboard, glad to have you! Take a look at the Tutorials sub-forum, I'm sure it will be of great use to a new player! (and there are also tutorials on more advanced concepts for when you're more experienced) Regards, Northstar

There was nothing impossible to accomplish about the Timberwind design. It was on-schedule for testing only a short time after when it was cancelled. The *ONLY* reason it was never built was due to the secrecy of the program being compromised and public/congressional outcry against the use of a nuclear rocket. Oh yeah, and budget concerns- can't forget those (basically any major new rocket technology project has been cancelled due to budget-concerns by Congress, which cares 100 times more about developing nuclear weapons than developing nuclear rockets...) Also, on an ENTIRELY DIFFERENT note, I've found evidence that you probably should have never rolled back the reductions to the thrust ratings of LH2/LOX engines compared to their hypergolic and Kero/LOX fuel-modes. See the following quote from this page on SSTO's: "While kerosene tanks can be 1% of the weight of their contents, hydrogen tanks often must weigh 10% of their contents. This is because of both the low density and the additional insulation required to minimize boiloff (a problem which does not occur with kerosene and many other fuels). The low density of hydrogen further affects the design of the rest of the vehicle  pumps and pipework need to be much larger in order to pump the fuel to the engine. The end result is the thrust/weight ratio of hydrogen-fueled engines is 30–50% lower than comparable engines using denser fuels." I *KNEW* Hydrolox engines are you currently had them implemented were too good to be true! All hail the one true king of REAL rocket engines- Kerosene! (at least until Meth/LOX starts seeing more serious development) Regards, Northstar