Zhetaan

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  1. Zhetaan

    Detachable ring structure

    It appears to me that you have something somewhat like the descent and ascent stages of the Apollo LM, but with rings instead of stacks. I can't think of any reason why it shouldn't work, aside from the ring problems that have already been mentioned. With that specific design, you may find a need for ReCoupler to avoid torsional shifting once you detach the ring structure, especially if the terrain where you land is not perfectly flat. It wouldn't do to land perfectly and then have the ring fall apart on you. I'd also caution you to turn down the force on the radial decouplers to zero. Otherwise, your issue is going to be the precision piloting necessary for both landing and takeoff, but I will assume that you have that part under control.
  2. One Poodle. If you insist on taking the O in LFO, then nukes have to haul that as dead weight. That makes it payload, and that utterly destroys your delta-V because it not only eliminates fuel from the wet mass side of the mass ratio, but it also puts that former fuel on the dry mass side. You cannot win on efficiency by using a nuke with a full bipropellant tank. Another thing to remember is that the mass ratio of the rocket equation doesn't care what the fuel is, but in order to compare engine efficiency (in the form of specific impulse) as an independent variable, you need equivalent masses of fuel (and rocket). Putting aside the actual masses involved, let's just say that the big orange LFO tank has twenty total mass units of fuel, in the proportion of nine LF to eleven O. The Poodle, which consumes LFO in that proportion, thus has the use of all twenty mass units. A nuke, to be fairly compared, also needs twenty mass units--but those units need to be all LF because that is what the nuke uses as fuel. Failure to provide that results in a rocket that has less than half the fuel load of an equivalent LFO engine, and to measure the nuke's performance against an LFO engine that has not been so hobbled is not a fair comparison. To wit: your example rocket is 53.589 tonnes from the readout. Subtracting the 2.7436 tonnes of LF and 12.3794 tonnes of O that you have in the image gives a dry mass of 38.466 tonnes. Assuming that the orange tank is full adds 32 tonnes of fuel mass for a total of 70.466 tonnes of rocket. The Poodle has a vacuum specific impulse of 350, so the rocket equation for this vessel is: delta-V = 350 * 9.80665 * ln (70.466 / 38.466), which gives a total delta-V of 2077.78 m/s. The Nerv has a specific impulse of 800, but it can only use the 14.4 tonnes of LF in the tank; the remaining 17.6 tonnes of O must be accounted as dry mass. The total mass remains the same, of course, but the dry mass for this rocket under Nerv thrust becomes 56.066 tonnes. The equation for this is delta-V = 800 * 9.80665 * ln (70.466 / 56.066), which gives a total delta-V of 1793.45 m/s. Shut the nuke off and leave it off. It's still three tonnes of dead weight, but that's better than 17.6 tonnes of useless oxidiser.
  3. Zhetaan

    Mastodon Engines on Eve

    Thanks for the check, @OhioBob. I keep getting errors because my approach is inaccurate. May I ask after the method you're using to model the curve? The changelog on the wiki says that Eve's pressure curve was redone in v1.2, but that page also has the outdated graphs, charts, and tables--don't trust the information there. Good catch, @FinalFan.
  4. Zhetaan

    Mastodon Engines on Eve

    @Xurkitree: At 7000 m, Eve's atmosphere is approximately 1.7 atm of pressure. Sea level is 5 atm of pressure. The quadratic spline says that the Mastodon's Eve sea-level Isp is about 180-190 and its 7 km Isp is about 265-275. These are very rough guesses, so please take them with the entire shaker of salt.
  5. It gets faster when you condense long and complicated terms such as National Novel Writing Month to short acronyms such as NaNoWriMo. Right now I can save you a bunch of time: On a much more serious note, I'm glad to see that you're still at it. I admit that I was curious to know how you would tie the backstory back into the main plot in such a way that the backstory would be satisfying, wouldn't feel rushed, and yet would still leave enough questions unanswered to keep the main plot full of suspense, but it was only curiosity, never doubt. To be honest, I'm wondering why Squad isn't tapping you to write a bunch of story-type Making History scenarios--unless they are and I should speak no more of it.
  6. Zhetaan

    Satellite bombs?

    I've not myself tried it; the closest I've come is a stack with separators or a set of three mounted on an inverted tri-coupler where the sats have enough of their own fuel to make course corrections but rely on a common booster to place them in their respective orbits. However, I think that this sort of thing can work for the right application, and I think that your best applications are in an extremely elliptical orbit or in an interplanetary transfer. If you release the cloud at the apoapsis of an elliptical orbit, then you have the benefit of a vast range of periapsides--of course, you have to deal with losing potentially half of your cloud to the planet--but such a cloud will disperse much more quickly. On the other hand, if you send out a sort of shotgun blast of cubesats while still some ways out from an interplanetary target, then so long as the central core is a dummy that you don't mind sending straight into the planet, the cloud will pass around it in a sort of rough ring for the same reason that interplanetary correction manoeuvres are so inexpensive: when you have enough distance, a pulse of even centimetres per second can make a difference of millions of kilometres at the destination. What use this could be to you is the subject of a different discussion, but for my part, I've always wanted to try fly-by scanning with SCANSat, and this may be a way to get more than one track of coverage. It probably will be hideously expensive, though.
  7. Zhetaan

    Interplanetary from Minmus

    There is a lot to be said for this approach if you want to get the most out of refuelling but don't want to take a lot of unnecessary hardware with you to points out-system. Provided that you're willing to establish the refuelling infrastructure and standardise your rocket design to be compatible with the booster, it pays for itself the second time you use it because it gives you the same principal advantage as an SSTO: reusable hardware. In some ways, it's even better (e.g.: no wings in vacuum). However, since you also ask about and to that I will say that it is only easier if you start measuring after you get there, and only in terms of fuel use--planning such a departure is usually harder because of reasons already mentioned by others. Keep in mind that without refuelling, you still have to spend the delta-V to get to Minmus's orbit, and that cost counters the savings you get from the Oberth dive (the 'easier' departure) because conservation of energy applies. However, there is one 'exception': if you split the interplanetary transfer burn so that the first burn establishes an apoapsis at Minmus's orbit but keeps your periapsis at LKO, then you get some of the advantage of the Oberth effect even though you're starting from low orbit, but this is actually a different technique called periapsis kicking. I'll put the details in a spoiler: The important bit is that you start at low circular orbit, but you limit the burn time at periapsis to about a minute (perhaps up to two minutes, if you have especially weak engines and don't want to leave completing the manoeuvre to your grandchildren) because anything not at the periapsis wastes the Oberth effect. Then, on the next pass, you burn for a minute centred on the periapsis again, and again after that. Each of these burns at the periapsis 'kicks' the apoapsis higher and higher until you raise it to nearly the boundary of the sphere of influence. The next and final burn is the one that sets up the final interplanetary transfer. Planning for this kind of departure is not difficult: set up the interplanetary manoeuvre as you normally would, but set it up well in advance: two 'minths' of lead time should be your minimum time and you may need more. The node will be in the same place as your eventual periapsis (that should make sense), but remember that each kick will change the orbit and thus also change the positioning of the final burn node, but we can use that for timing later. The second-to-last burn will be less than a minute because this is what we will call the 'timing burn': burn so that your orbit brings the node and the periapsis together. In other words, you want the time-to-periapsis and the time-to-node values to match. This may leave your apoapsis a little short of Minmus's orbit, or you may get the timing slightly off, but that's okay: transfer windows to other planets are within acceptable tolerances for a week or more, so don't fixate on the 'perfect' transfer. You can use MechJeb's node editor to figure a lot of this part, but it isn't necessary. There used to be a mod for that, but it hasn't been updated since 1.2.2.
  8. Why weren't these included as space suit variants for 1.5? I'd absolutely take Skebediah, Count Bobula, and Dr. Franken-Bill's monster on a mission to see whether were-kerbal-wolves still turn on the far side of the Mun. ... And also to see whether Minmus is made of mint candy. That part ought to be obvious.
  9. Zhetaan

    Funding bug in career mode?

    It's balanced, but the balance is skewed to favour ease over difficulty. Consider, for example, that with the default science sliders and stock tech tree, it's possible to complete the entire tech tree without leaving the Kerbin-Mun-Minmus system. When you add the sheer magnitude of science multipliers and other opportunities available in the solar system, it's enough to question why anyone bothers with science at all at places such as Duna and Jool. Part of that, I think, is a remnant of the days when only Kerbin, the Mun, and Minmus had biomes, but it's also the case that the devs have had many opportunities to further change the science point balance and chose not to do so. If you've spent some time in Science mode, then as you say, you've got experience with KSP. That means you're good enough at flying different kinds of rockets (and without instant availability of the most capable rocket parts) that you don't have to worry so much about crashing and burning, and can easily afford to turn the funding slider down to 30% or lower because you won't have to pay for many mistakes. Depending on how you feel about the MPL and research, you can probably afford to turn down the science sliders to 20% or 10%, and force yourself to go out-system.
  10. One of the cons would be the notion that the International Astronomical Union has any jurisdiction in interplanetary space--it's in the name, after all. So in that case, yes, I think the Jool would be a good name for the next craft to visit Georgium Sidus. Another would be that no one bothered to compare the rate at which we create myths to the rate at which we discover planets. There are quite a few planets that will remain catalogue numbers for a long, long time--possibly forever--so it's not completely outside the realm of possibility to assume that someone will invent a classification system that is independent from the availability of various pantheons. Actually, on that note, I wonder whether the IAU will be forced eventually to revisit the suitability of certain religious sources given that some of the ones listed appear still to be active. By that I mean to say that it would be improper to assume that a Hawaiian religious adherent, for example, would necessarily be pleased to see Hawaiian religion used to name rocks in the sky, so perhaps we will find ourselves needing to rename Haumea at some point in the future.
  11. That's what the acknowledgements page of the novel is for. Or, if you're very impressed, the dedication. ... Personally, I'd go for the dedication. Anyway, somewhat more on topic, how's the chapter thus far, @Just Jim? Not by any means to insinuate that the writing is my first concern, but is the hurricane season threatening to blow you straight to Oz again?
  12. True enough. I can't imagine how much chaos would ensue if Squad made KSPedia user-editable. To illustrate the issue a little more thoroughly, the 9.8 m/s2 came about because it eased some difficulties with conversion between imperial and metric units (seconds being one of the few units the two systems have in common). You are correct in that a rocket engine's design (and resultant efficiency) shouldn't change with the body it orbits. In the original formulation, the equation for delta-V is this: Δv = vexh * ln (mw / m0) Where: Δv = delta-V, naturally, ln (mw / m0) = the natural logarithm of the wet/dry mass ratio (this part is the same in both versions), and vexh = the engine's exhaust velocity. I can show you how to derive that, if you like, but the point is that I find this formulation much easier to understand: if the mass ratio is higher, then that is because either the amount of fuel is higher or the amount of payload is lower, so the rocket can do more. That makes sense: I know that adding fuel and lightening the payload both increase delta-V. If the exhaust velocity is higher, then it means that the propellant has more momentum, and while that can be true for a number of different reasons (including better propellants and more efficient engines), the important part is that if the exhaust has more momentum, then the rocket does, too, so it can do more. That should also make sense: the basic function of a rocket is to go forwards by throwing mass out the back, and conservation of momentum means that if I throw that mass out the back faster, then I also throw the rocket forwards faster--which, functionally, is an increase in delta-V. What often makes less sense is that more efficient engines always get their delta-V increases from a higher exhaust velocity. It may seem odd that a Terrier has a faster exhaust than a Reliant when you put them side-by-side. It's true, nevertheless: the Terrier squirts out fuel at a blistering rate compared to the Reliant, but it doesn't squirt out so much at a time. That results in high efficiency but low thrust. To better illustrate this, consider the extreme: the Dawn ion engine essentially works by accelerating the propellant atom by atom, but it accelerates those atoms to insane velocities when it does so. That results in equally insane delta-V (and correspondingly low thrust). It also explains why engines have poorer efficiency when in an atmosphere: when they have to squirt out the exhaust against atmospheric pressure, that back pressure slows the exhaust stream from the engine, which reduces delta-V.
  13. Zhetaan

    SENTINEL Telescope

    In addition to the asteroid hunting that's already been mentioned, the SENTINEL telescope has a science experiment, but it only operates in high orbit. For Kerbin, that's over 250 km. The restriction is similar to those of the seismometer (it won't work if it's not on the ground) or the atmospheric analyser (which won't work if there's no air). If you're sending a SENTINEL to solar orbit, then you may wish to fly it by the Mun or Minmus and take advantage of the opportunity to get the science results from high Mun or high Minmus orbit. @400poundtuna: However, to generate and send these science results, yes, it does require the typical science probe kit: electrics, probe core, antenna, and all that. Though the camera is unusual in what it can do, the science experiment module works in exactly the same fashion as every other experiment part.
  14. Did you mean Moho or Minmus? Then visiting it anyway is the pinnacle achievement of the game. Anyway, in the interests of sincere advice, @Kerbal007, I will offer that your main concern is that you're not thinking about a big enough goal. You've decided to follow something that approximates actual history: I invite you to consider how, historically, these sorts of missions were planned. As a case in point, consider that President Kennedy committed the United States to landing a man on the Moon (and returning him safely to Earth) before the end of the decade. At the time he made the announcement, the only manned space mission that the country had completed was Alan Shepard's suborbital flight aboard Freedom 7. From that point on, everything--especially everything Gemini and Apollo--was directed to achieve that goal. There were unmanned test rockets. They learned how to rendezvous and dock in space. They figured out how EVAs work. They tested the manned modules in Earth orbit. They tested them again in lunar orbit. Then they finally landed on the Moon, and the landed missions grew more complex, as well. Take a look if you're interested in some of the different mission types. My point is to say that you can do things like this quite readily in KSP; you have an entire solar system to play with. Let's imagine, for example, that you want to fly a circumnavigating aeroplane around Duna. Call it a D-Prize if it strikes your fancy. Flight on Duna is possible but it's not at all like flight on Kerbin. To make that happen, you'll need to run an entire battery of tests, get the science needed to unlock the right plane parts, figure out your engines, fuel, and general mission parameters, design something that can fly in Duna's atmosphere--which may involve taking unmanned test gliders just to see which ones work--and let's not forget to provide means for those doing the piloting to return to Kerbin. And, of course, that's just from the one planet, and includes neither the design of the surface-to-orbit delivery rockets and interplanetary transfer rockets that you'll need, nor the skills to fly them correctly. Have fun.
  15. Zhetaan

    Most efficient way to turn back

    @laythe depression: To start, welcome to the forum! I think that the thing to remember is that Ike orbits Duna with a sphere of influence of only about one million metres. Duna's is nearly fifty times larger. Your Ike-centric inclination is extreme, but your Duna-centric inclination is going to be much less so. Add to that the fact that though Ike has somewhat low gravity, its small sphere of influence means that your orbit is always going to be very close and thus inclination changes will be expensive. There is probably a point where it's cheaper to make the change at Ike and then go to Duna's sphere, but if your intention is to make an interplanetary trip, then you'll probably want to transfer out to Duna high orbit and return from there, with or without a dive for Oberth effect assistance as you see fit. However, if you want the most efficient return, then that would entail using both your orbit around Ike and Ike's position to effect an Oberth dive nearly to Duna's atmosphere at the right time to get a Kerbin transfer. However, without a fuel depot to offset the cost of setting up the encounter in the first place, the savings probably aren't worth the trouble. Duna and Ike just don't have enough gravity.