Starman4308

I am personally imagining some toggle in the map view, which when set, gives you the approximate transfer windows as color-coded sections on the orbit of your current body. So, if you had a Jool transfer window in the next Kerbin orbit, that window would show up as a green patch along Kerbin's orbital track. That, or have some sort of protractor function built-in so you can measure phase angles at arbitrary points of time, possibly with a little notepad attached so the person can write down a table of phase angles.

A, if you like planes. B, if you care about cost efficiency: an SSTO spaceplane is far more efficient than a rocket. C, if you want to biome hop on Kerbin without a single non-enormous vehicle. D, if you want to explore places like Duna and Eve from within the atmosphere in short time-frames.

Well, if you weren't averse to manual number-crunching, you might try exiting Minmus far ahead of time, and tweaking orbit so that, when the launch window comes (technically a few days before the launch window comes, to provide time to drop down from high orbit), you are directly opposite the burn location. There's some leeway, because the launch window has leeway, but you'd have to set up your orbital period such that you're at the right phase when the launch window comes.

The whole point of crew reports is to encourage manned missions, instead of just doing everything with 40kg OTKO2 probes. Adding probe core-specific science would A, defeat this purpose, and B, be non-sensical, because a manned mission should be able to do everything a probe can*. *Unless you care about your Kerbals, in which case you probably don't want to do a one-way trip to the bottom of Jool.

There is one non-gravitational reference I can think of where the Oberth effect is meaningful: "George, George, George of the Jungle, strong as he can be, watch out for that tree!"* *Technically this specific example involves gravity, but if you had something about to collide with you in deep space, gravitational reference frames are not particularly relevant at the moment, but kinetic energy is certainly relevant. EDIT: Basically, the Oberth effect is relevant whenever kinetic energy is relevant, and that is not constrained to orbital maneuvers.

I suspect we're talking past each other. My point is that I am pretty sure the rocket's kinetic energy gains out of the Oberth effect are not because "you are getting more out of the chemical energy of the fuel". This is clearly ridiculous, because if you apply thrust at 0.9c, the amount of kinetic energy your rocket gains is vastly in excess of the chemical energy from the fuel. Instead, I am pretty sure your kinetic energy boosts can be explained by the fact that the exhaust gases are losing a commensurate amount of kinetic energy, possibly with a wiggle factor no greater than the useful work generated by burning propellant. I am not disagreeing. As mentioned, this should work. It might burn more fuel overall in some cases*, but I am pretty sure it'll let you get away with smaller fuel tanks on your vehicle, because the amount of dV spent going from a circular high orbit to an elliptical high orbit should be less than the amount of velocity you can add to the slingshot. *For example, if your target is "just barely escape Kerbin", you're burning almost enough fuel to escape Kerbin, refuelling, burning a bit more to set up the slingshot, and then burning a substantial fraction of the fuel necessary to escape Kerbin: this is in addition to the fuel it took to set up the fuel depot in the first place. More overall fuel expenditure, though neither maneuver (getting to the fuel depot, or setting up the slingshot plus slingshot) uses as much fuel as a direct burn.

I thought you were having issues with trying to understand how a burn straight from LKO was more efficient than escaping, and then going somewhere? In any case, I am 99% sure the "chemical energy explanation" is bunk, because conservation of energy has to be true no matter what silly reference frame you choose (magic rocket going the other way at 0.9c, for example), and the differences in KE are greatly exaggerated in some reference frames, leading me to suspect that's not exactly what's going on.

Okay, perhaps I can take a crack at this. As mentioned, the Oberth effect favors burns at high speed. One way to think about it: if you escape Kerbin very quickly, Kerbin's gravity has less time to claw away and try to eliminate your escape velocity. If you just barely escape LKO into the same orbit as Kerbin, the amount of orbital velocity lost to Kerbin gravity is at a maximum. If you burn straight from LKO to, say, Jool, you will be escaping much quicker, so you will lose less velocity during Kerbin escape. Both ways of going to Jool will have the same velocity exiting Kerbin orbit, but the two-burn strategy loses some because you dawdled in Kerbin's SOI and lost more velocity to gravity. That is why Oberth favors transfers direct from LKO* in delta-V terms: you lose some velocity escaping Kerbin, and the faster you escape Kerbin, the less velocity you lose to gravity. In kinetic energy terms, GoSlash is almost exactly right: because a direct transfer lets you add the velocity from orbiting Kerbin, you get the same kinetic energy for less change in velocity. The goof: I am pretty sure Oberth doesn't have much to do with the chemical energy of the rocket: conservation of energy is maintained because your fuel is losing kinetic energy equal to the energy your rocket is gaining. I have no idea where the chemical energy is going (probably heat, for the most part), but it is patently ridiculous to conclude that you are getting "more out of your chemical energy", because as you increase velocity, you will swiftly reach the point where kinetic energy per kilogram of propellant burned exceeds that kilogram's chemical energy. There's also the little bit that energy should be conserved no matter what reference frame you're in. There's probably some fancy mathematical proof which states that, for a momentum engine (a rocket), energy gained between all potential energy fields (gravity wells, etc) and reference frames (magic spaceships traveling 0.99c in the other direction) is equal to energy lost by the exhaust, again in all potential energy fields and reference frames. Maybe there's a bit of leeway, but it would have to be strictly less than the useful energy gained from burning the rocket fuel, because of conservation of energy. *Or possibly straight from the pad. I've always set myself up in a parking orbit before interplanetary transfer.

Only in maneuver node land, where burns are instantaneous, is this true. In practice, because burns are not instantaneous, you will always be a bit short of the target orbital energy, and will need to perform a correction burn to get you back on course: this correction will require more delta-V for a low TWR vehicle. In an indirect way, Oberth is about fuel flow rate as said. The faster you can thrust, the better you can exploit the Oberth effect, because you're performing more of your burn at high velocity. I am, however, completely certain you are misunderstanding what the Oberth effect is, because the Oberth effect is all about the velocity through the course of the burn. Yes, because KSP simulates Newton's laws of motion in a system with Newtonian gravity. The Oberth effect is an orbital mechanic, and KSP simulates orbital mechanics. You're living in maneuver node land. In maneuver node land, all burns are instantaneous and make maximum effect of the Oberth effect. In the real world and KSP, if you perfectly complete a maneuver node, you will find yourself not quite having reached the target orbit, because the burn did take a finite amount of time. If your acceleration was low, you will be particularly far off-course in a significantly lower-energy orbit than the target, because it did not maximally exploit the Oberth effect. No, burn time is a function of thrust, vessel mass, and some dependence on specific impulse, being mostly a function of how quickly the engine converts fuel into the requisite delta-V. The only dependence on efficiency is a negative one: if you have a very efficient engine, you will burn through fuel slowly, so your acceleration will not increase as much, prolonging your burn time. Given two vessels identical in every way but TWR, the higher TWR one will get a slightly better boost out of the Oberth effect, by dint of throwing an identical amount of fuel out the back more quickly. Patently false. To make a concrete example out of the above, imagine you had two identical vessels, with one having its thrust limiter set to 10%. Delta-V = Isp*G*ln(full/empty mass): there is no dependence on thrust or acceleration anywhere. Both can manage the exact same burn using the exact same amount of fuel, but the 10% one will take 10x longer: it is applying 1/10 of the force for 10x longer, performing it in slow motion. When you integrate force over time (which is basically the rocket equation) for a momentum engine (a rocket) to get a change in velocity (after dividing by mass), it doesn't matter how quickly you thrust, it only matters how fast the exhaust is, and what your full/empty mass ratio is. I have never seen this. Again, to the best of my knowledge, maneuver nodes are calculated based on instantaneous acceleration. Or, perhaps more accurately, the projected orbit from a maneuver node is calculated based on instantaneous acceleration.

Delta-V in KER is, to my knowledge, exact*, following the Tsiolkovsky rocket equation (dV = G*Isp*ln(fuelled mass/dry mass)). Geschosskopf was simply confused as to how the Oberth effect works. *Plus or minus a tiny fudge factor to account for imperfections in the KSP simulation: it must apply thrust and consume fuel in discrete quantities, and is subject to the limitations of machine precision, which means rockets will not exactly follow the equation. I doubt the error will come to even 1 m/s in most cases. However, the delta-V maps are all approximations, because the exact amount of delta-V required depends strongly on how you manage your maneuvers.

One non-mathematical way to think about it for transfer burns: the longer you spend burning, the more time gravity has to claw back some of that velocity, and you have to add additional velocity to compensate for that loss. The more mathematical way: kinetic energy (minus relativistic effects) is equal to 1/2 m*v^2. Accelerating a 1kg object from 100-200 m/s will give it 15,000 J of kinetic energy. Accelerating that same object from 1000-1100 m/s will give it 105,000 J of kinetic energy. You've spent 100 m/s of delta-V either way, but in the second case, you've gained a lot more energy. You are incorrect. Fuel is delta-V: dV = G*Isp*ln(fuelled mass/dry mass): for a manuever of any given delta-V, you must burn fuel equal to e^(dV/G*Isp) * fuelled mass. The Oberth effect, as mentioned, deals with the fact that you get more kinetic energy at high velocity, because kinetic energy is proportional to v^2. EDIT: Also, if you are confused about whether this violates conservation of energy: it doesn't. While you're adding kinetic energy far in excess of the fuel's chemical energy, the exhaust gas is also losing a commensurate amount of kinetic energy (with respect to the present orbital body, and presumably all gravitational fields).

For a homogenous engine setup, easily proven mathematically impossible. The most mass-efficient tanks have a fueled/empty mass ratio of 9/1. In the rocket equation, that puts a hard cap of 2.197*G*Isp on how much dV a single stage can have. A short calculation assumes 390 Isp and zero payload/engine mass, for 8414 m/s delta-V. This is just barely enough to get to orbit from a high altitude, and completely and utterly neglects engine/payload mass. The optimal engine for a TWR of 1.7 (Eve surface gravity) is the KR-2L, with a vacuum Isp of 380s and an Eve TWR of 23.03. This means an upper bound of 22.03t of fuel tank per ton of KR-2L, or you will literally sit on the surface burning fuel until you can get off the ground. Take the inverse, and you've got to add 0.0454t of KR-2L for each ton of fuel tank, thus your fueled/empty ratio is now 9.0454/1.0454, for 8.65. Plug that into the rocket equation, and you now have 8052.29 m/s delta-V. In practice, you will lose a lot of this delta-V to a combination of gravity drag and sea-level Isp values, because this rocket is literally just barely capable of getting itself off the ground when full. You will not get to orbit with this rocket. While the math is more complicated for a heterogenous engine setup, there are practical arguments to suggest it is impossible: every ton of LV-N will reduce your fuel ratio for the KR-2Ls, and the KR-2Ls will add a lot of dry weight for the LV-Ns to haul when you switch over. I strongly suspect you'd never be able to make a KR-2L/LV-N setup work; the KR-2Ls don't have the efficiency, and the LV-Ns don't have the thrust, and using both exacerbates both of these problems.

While slow framerate is usually a factor of weak CPU (or really weak GPU), I'm suspecting the same thing as Lale: while 32-bit KSP can't use more than 4 GB memory, with a lot of mods, it could hog the entire 4 GB RAM on your computer, and since background processes also need memory, something has to give, and that is to start sending stuff to hard drive, which takes an eternity to access. I suggest Active Texture Management, and if that doesn't work, just deleting mods, or some of the parts/textures from mods.

Maybe bring it up casually during the interview, but it just seems terribly unprofessional to put "I played a video game" on a resume, no matter how applicable it is.

Wow, this will really help with spaceplanes, because now there's much less fear of tailstrikes when you try jacking up the nose for takeoff lift. I've always been annoyed at the shortness of the stock landing gear.

Gotta agree on having a starter-tech probe core; for those who RP on KSP, it is very silly to start manned. I like NecroBones's probe from Modular Rocket Systems: while it does weigh less than the Mk. 1 pod, it's got some disadvantages. It has no top node (and, thus, no parachute until you hit radial chutes), it has strictly limited duration until you get to solar panels/batteries, and you can't carry a Kerbal for those science-rich EVA reports. If something needs to be shifted later, the S1 SRB could be placed later, and the Mk1/Mk2 lander cans could switch places. The Mk2 is direly overweight anyways, and its use might help channel new players towards wide landers. One additional idea is to have conical fuel tanks (such as 1.25-2.5m) added, and placed later in the tree than their unfueled structural equivalents, which would help when Squad moves to a less stupid aerodynamics model.

You don't need high TWR to circularize. You only need high TWR for launch; otherwise, you can coast on a combination of the upwards kick from the lower stages plus lower effective gravity*. You'll spend a bit more delta-V due to having less TWR, and correspondingly higher gravity losses, but if you get enough delta-V out of staging, that'll get you closer to low Laythe orbit. *Mostly coming out of already being partway to orbit, with a tiny bit coming from having some additional distance from the planet's center.

Well, I found the opportunity to send Dodos Kerman on countless SSTO spaceplane rides too amusing to pass up, so there's that.

You may be able to increase your available delta-V, then, by transferring fuel into the upper stage, disabling the fuel tank, staging, re-activating the fuel tank, and firing the Ants. While the Ants are less efficient, you may increase overall available delta-V because you ditch the weight of the lower stage. You have not exhausted your options. Sure, it might scrub other missions, but if you would prefer to rescue without cheating, this is the way to go. And seriously: burn some of that RCS. If you do it right, you need just tiny touches of RCS to rendezvous and dock, and every gram of RCS used during ascent will increase your delta-V. Plus, if you have RCS aboard your orbital vehicle, you can use that to rendezvous. This is often the more efficient way to do it: the lander has to carry that RCS fuel back up to orbit, while if you rendezvous with your orbiter, you don't need to bother carrying the RCS back up. The exception is if you have a very lightweight lander and a heavyweight orbital vehicle, because it costs more RCS to maneuver a heavy vehicle.

You're going to need a multi-stage monster to exit Eve atmosphere, particularly if you do so from sea level. With stock aero, you're probably looking at an asparagus-staged pancake for maximal efficiency and a wide landing base: try to land it on elevated terrain, so you've got less souposphere to fight through. Eve ascents are one of the most difficult things in KSP, so don't feel disheartened if you can't manage it. One important consideration: you probably do not want to try a direct return from Eve; you should rendezvous with a separate return stage in orbit, Apollo-style. This keeps you from needing to bring the return stage down, and then painfully bring it back up through Eve's atmosphere. With FAR/NEAR, stuff gets very interesting, because the ascent stage should preferably be slim and aerodynamic, but you still want a wide landing base so as to avoid tipping over; the probable solution to that would be having most of the ascent stage be a narrow rocket, with its first stage being a short but very wide landing base.

I don't know what the weight limit is, but there are three solutions to the problem. #1: Turn off destructible buildings. #2: Use Claw's stock bug fix for the problem: it basically flashes indestructible buildings on for a few moments during physics load. #3: Launch clamps, and if necessary, structural panels extending from the launch clamps to shield the exhaust.

Looks like good stuff Clockwork. It's not something I personally need (FAR gives plenty enough reason for aerodynamic nose cones, etc), and it might conflict with RealFuels, but it is definitely worthwhile for many. Just one quick comment: give the rules a lookover. I'm pretty sure the post needs a license, and you need to have a link to the source code if applicable. As it seems yours is a config file with Module Manager attached, I am pretty sure source code is not meaningful, as it is all included as raw text in the download anyways.

First off, those delta-V maps are approximations; exact delta-V requirements depend on TWR profile and how you manage your gravity turn. Double check that you're accounting for atmospheric Isp: if you've got a vacuum engine, you might be losing a good amount of delta-V during the initial ascent*. There could also be issues with an imperfect gravity turn or a bad TWR: if your engine is struggling to get off the ground, you'll lose a lot of delta-V during the first part of the ascent, and if you're going horizontal too quickly or too slowly, that also burns up delta-V. I unfortunately can't give you much guidance on how to do an optimal gravity turn: I've never been to Laythe. I imagine it would be more horizontal than Kerbin ascents, courtesy of the thinner atmosphere, but the optimal turn requires simulation, either mathematical or just by trying until you get it right. *One thing which helps is that air gets thin very quickly, so if you're not dawdling in sea-level soup, you reach near-vacuum efficiency very quickly. One rather spectacular example is the LV-N, which reaches 390 Isp before it reaches 2 km altitude at Kerbin. Otherwise: time for a rescue misson, or alt-F12, depending on your patience level. EDIT: And if you've got any monopropellant, you're going to have to figure out if you want to use it or if you want to dump it. In theory, it's rocket fuel, and since it has low specific impulse, you'd want to use up the monopropellant at launch or shortly thereafter (the issue is that, since RCS such a large vacuum/sea-level Isp ratio, it might be worthwhile to hold onto it for a few kilometers). In practice, that approach would require some fancy footwork, as you'd need to rapidly switch between staging mode, to turn the craft and fire stages, and docking mode so you can hold down W to translate forwards. If you don't want to deal with switching so often, the question becomes simple: do you get more delta-V by hanging onto that monopropellant until the LF/O rockets are exhausted, or do you get more by burning all of it before launch?

Personally, particularly with regards to return missions, I am a fan of "Evil" for Eve. For serious adjectives: Kerbol: Kerbolar Minmus: maybe Minmal? Duna: Dunar Jool: Joolian

Are there any plans to fix the issue where keyboard entries to mod GUI windows aren't shielded? For example, say you were typing "Long Endurance Mission" into your Kerbal Alarm Clock window, and the game decides to stage off the decoupler with all your life support for said long-duration mission because you pressed spacebar?