PLAD

OK, It's fixed now. I've put up FFRSS version 0.85 in the OP. Changes from version 0.84 are that the Earth's starting position, change in anomaly per day, and SMA have been adjusted to sufficient accuracy. Anomaly and start postion were off by about one part in 1000 in 0.84, so Earth would be about a third of a degree further out of position every year. I also tweaked some of the planet diameters and atmosphere heights that changed a bit in RSS v12. I saw that Pluto has an atmosphere now, but it is so thin that I let FF ignore it, I figure Pluto isn't going to change your course a bit if are going fast enough for that atmosphere to affect you.

Argh, I've been running series of flyby missions in RSS 12.0 and have discovered a bug in v0.84 of FFRSS. It is only a problem when in V12.0 mode, I didn't enter all the new parameters correctly and FF will give increasingly bad results as the years go by (though the first few years the error is trivial). I think I've nailed down the error and am testing a fix now but it will take another day or two to be sure. I shall remove version 0.84 for now because I don't want anyone counting on it. Sorry about this. -PLAD

This is an impressive planet pack! Bundling the visual mods with the configs set up for it is a great idea, this system is gorgeous right out of the box. Including a delta-V chart and tables of planetary parameters is a nice touch too. I particularly like the orbits and masses of the planets, as they give lots of possibilities for gravity assist chains. I have added this system to Flyby Finder V0.84, for those who like to try and get to far away places as cheaply as possible the release is here. Below is an album where I go from low Gael orbit to Tellumo-Otho-Gauss-Nero with one 1446m/s start boost and about 8m/s of course corrections. Thanks for making and releasing this pack! http://imgur.com/a/xUNHe

Just a note, I've added a new version of FFRSS, it is now V 0.84. The only change from V0.83 is that I added a couple of radio buttons to allow you to select between using the value for Earth's SMA used in all versions of RSS before V12.0, and the (more accurate) value used starting in V12.0. The default on starting the program is the V12.0+ value, so there is no need to upgrade to FFRSS 0.84 until you start using V12.0. The change is pretty small, you wouldn't really notice different results until you're in the 1960's -PLAD

I have just just released version 0.84 of Flyby Finder. The one change from version 0.83 is that you can now do searches for Galileo's Planet Pack (current release, version 1.1) as well as the OPM and stock KSP Edit: Below is an album showing how I executed a Gael-Tellumo-Otho-Gauss-Nero flight. On reflection I should have corrected that 9-hour delay in the Tellumo arrival time that the Gael departure burn inaccuracy created, as every flyby worsened the error by several times. The gas giants are forgiving of fairly large errors though, and I just hate to use a drop more of fuel then necessary. http://imgur.com/a/xUNHe -PLAD

That is superb, thank you for posting this note. -PLAD

Yes, high inclination flights are quite difficult for me too, I avoid them when I can. They are terribly sensitive to the time of periapsis. When flying one it is much more important to get the time right than the Vsoi or flyby altitude. Wait and use a mid-course correction if it is too difficult to get the time just right with the previous encounter, but if you are way up out of the ecliptic plane an MCC can be too expensive.... I don't know if you have checked out Arrowstar's TOT, it is much more complicated to use than FF but it gives a lot more information. When doing flyby calculations it only gives one flyby within the search windows you set (instead of a plot of many possible flybys like FF) but you could use FF to search for a flyby sequence you like, then run TOT using very narrow search windows so TOT will be forced to find the one you want. TOT then shows a graph of the overall path and details of the flybys. It will probably still be a chore to get a high-inclination flyby just right though. You can use Okder's addon (see the first post in this thread) to set up the first leg of your trip precisely for you, if you have Mechjeb installed.

@aluc24, I'll answer the questions in reverse order: -Yup, the calculator takes atmosphere height into account, if a flyby would have to go into the atmosphere it is rejected. I originally tried ones that went just a few Km into the atmosphere, but the Oberth effect made the few m/s that the atmosphere took away into a much larger reduced speed at the SOI and severely messed up the flights. -I decided to stop at 4 encounters for two reasons, one is that it would be too tight a squeeze to put two more rows of numbers in the output table, and the other is that I found it hard to stay on course for that many flybys, by the 4th one I'm usually many days or even months off from the desired time unless I use a lot of MCC's. -You've discovered a weakness in the program, in certain situations it stops responding to inputs while it is running the search. It seems to happen when a "search period" divided by 'search steps per period' is below a certain value that depends on the outermost planet's orbital period, but I have never nailed it down (though I try from time to time). The 'checking day' box only updates when the "start at" search day is incremented, so if there are a lot of bodies there can be a long time between updates of that box, I didn't want to add the time it takes to update the box to the many thousands of search loops below that. Try lowering the "search steps per period" (SSPP) for a preliminary search, if it finds something note the time taken, then increase SSPP keeping in mind that doubling it increases the run time by 4X, and at some point it might start the no-response error but it will still complete the search. Sorry about that.

@DBowman I tried this path out and I see the issue- the required start equatorial Z and start equatorial prograde values are wildly sensitive to the flyby time with this particular flight. For instance if I leave Earth at day 26535.1 and pass Venus on day 26699.4 it requires a start z of -10329m/s and a prograde of -2663, but if the arrival time is changed to day 26699.6 then the z has to be -10277 and the prograde -2560m/s. So 4.8 hours changes the z by 52m/s and the prograde by 103m/s. In other words it takes a big change in start v to make a small change in arrival time. Flyby Finder has a lot of operations to find a flyby and trigonometric rounding errors build up in a sensitive path like this, and I can't think of a way to make it more accurate without a big hit in run time. So I live with sometimes having to adjust the prograde and z values from the values output by FF. On the other hand, as you found, it is easy to get a good Mars encounter from a range of Venus flyby times. It is also straightforward to coast from there back to Earth, the problem is that your Earth arrival time can vary a lot- in the above example the 4.8 hour Venus flyby timing error can lead to a 5.5 day change in the Earth arrival time. So if you want a precise Earth return time for some reason you might be forced to make a number of large-ish MCC's to pull it off- keep trying to make each encounter happen as close to the listed time as possible. Sounds like you flew it well despite the roughness in FF. I think I see why you chose that path, it has a nice balance between low Earth arrival velocity and a short total flight time.

@aluc24 The travel time axis auto-scales to the range of the flybys found in a search. You told it to search for flybys that started at Kerbin with a certain maximum V at SOI in a certain departure window, and then flyby Duna within a second window, and then arrive back at Kerbin in a 3rd window. It found 828 solutions with those restrictions, and the longest travel time of those solutions was about 880 days, and the shortest about 760 days. You can calculate the longest possible trip by taking the earliest search date (day 1120) and subtracting it from the last possible 2nd encounter time (day 1930+ the 200 day search period=2130). This would be 1010 days in this case. The only way to have a larger range of travel times is to open the search windows and/or increase the max V at SOI. Note that Flyby Finder allows no more than 1 orbit around the sun between encounters so you will need a lot of energy to fly out far enough from the sun that you take more than 1000 days to get back to Kerbin. Try taking the exact search you have above except change the max V at SOI to 3000m/s, and change the 2nd encounter search period from 200 days to 1000 days, and you will see a new 'blob' of solutions appear that have a travel time of about 1250 days (~3 Kerbin years). This KDK trip is a fascinating one, try increasing the vSOI and search period more and you can find a solution blob that take about 4 Kerbin years, then 5, etc. Then expand the search start times and you will find a solution blob that flies by Duna on the way out from Kerbin, as well as blobs with about the same travel time but shifted in start time that flyby Duna on the way back toward the sun. At really high energies you can start to find trips that take about half a Kerbin year and 1.5 Kerbin years (these go out to Duna and then way in towards the sun and approach Kerbin from inside its orbit). Those are very small, when you first look for them you should probably have 'search steps per period' at around 200 or so, assuming your 'start at' search period is about 900 days (the Kerbin-Duna synodic period). -PLAD

I'm sorry Dave, but I can't do that.... There, I got that out of my system. @DBowman- I've found that the Venus flyby timing in an EVME path should be within about +/-24 hours to keep mid-course corrections near zero, so 32 hours late is risky in the sense that you might need something on the order of 50m/s of corrections to get the final Earth encounter. This looks like a high-z velocity flight too, and that makes the timing requirements even more tight. I'm going to have to set this one up myself to explore the situation, but that might take a day to get back to you so I'll tell you what my first try will be: First tweak the start equatorial prograde and z velocities a bit, I notice you have the values entered exactly, and in RSS z can be +/- a percent or so when the z values get high. Tweak z (or 'Normal') first. That should get you closer to Venus at the right flyby time. Next, live with leaving Earth at the right time on a path that takes you past Venus at the right time but fairly far off from the right flyby altitude. Try to make your initial orbit cross as close to Venus' orbital plane at flyby time as possible, be willing to be +/-18 hours off in order to do that. Then set up a maneuver about 90 to 180 degrees before your Venus encounter that corrects the flyby altitude, at this point you'll find that it won't change the flyby time as much. If you had a lot of z-error (flyby too far above or below Venus) the maneuver should be closer to 90 degrees before the flyby. Now you should be flying by Venus at close to the right time and close to the right altitude. But then, at a point 90 degrees before the Venus encounter you can set up the Mars encounter fairly precisely, and that will be more important than the details of your Venus flyby. Flyby altitude soaks up other errors, there is no need to worry about up to +/-20% error in flyby altitude. Changing the AoP of the departure orbit instead of the departure time is an approach I haven't used, I get the reason for it, because changing the departure node time by even 1 second can cause a change of tens of thousands of Km in the Venus encounter and changing the AoP allows greater sensitivity. But I change the departure node radial velocity by a few m/s to get the same effect as changing the node time, the change in the total dV is trivial and it is easier to adjust by pressing the radial + and - buttons than by typing in the AoP value.

Some time ago I searched for a variety of departure times for going from Kerbin to Duna, the premise was that it takes time to prep a rocket and launch pad for a mission so one would want to launch whenever the pad becomes available throughout an entire synodic period. By using different routes I found relatively low-dv launch windows all over the place, though the travel times vary quite a bit. Here's a chart showing the best paths I found during the first 226 days of the game. (Note: 24-hour Earth days, not 6-hour Kerbin days!) http://imgur.com/a/H8boT The Kerbin-Duna synodic period is about 227 Earth days, but if you are using Eve to get to Duna then there is a quasi-synodic Kerbin-Duna-Eve period of about 681 Earth days, so this chart should roughly repeat that often. More precise is to check the windows for the specific time you are interested in. Note that I use my Flyby Finder to find the flyby windows, but Alex Mun's porkchop plotter to find the multi-revolution Kerbin-Duna flights (where your ship goes more than once around the sun during the voyage). The multi-rev paths have long flight times though, I only use them for cargo missions. Every one of these flight types can be run in 'reverse' to get back to Kerbin from Duna with departure times all over the place. Starting with Duna-Eve is a big dv hit though. As for Eve, I've never looked, I would imagine K-D-E would add some windows.

The numbers used in the primer are in "Earth Time" (24/365). So the earliest search date is day 160 Earth time, which is day 637 in "Kerbal time" (6h/426d). Versions of FF after 0.60 start by default in Kerbal time, but earlier versions only did Earth time. (This happened because when I first wrote FF, KSP only did Earth time.) In any case the quickest way to translate them is to enter the numbers in FF when it is in Earth time mode just as they are in the example, and then click the little radio button to change FF to Kerbal time and proceed with the search. You will find the same solutions but now the dates and time of flights will be in Kerbin days, so that 138 (Earth) day flight will now take about 552 (Kerbal) days. Some parts of the primer still show screenshots from version 0.60, though I did put in a note that all screenshots up to the 'new features' section use Earth time. These two time systems have caught me more than a few times.

Yup, I've found the most important parameters to match are the encounter times and especially the time of the Eve periapsis. Each successive flyby can be a little sloppier but when doing KEKJ or KEKKJ the time of the Kerbal departure and the Eve flyby should be less than +/-6 hours off. If you are outside that window you can still make it but the corrections required start to increase dramatically, as it sounds like you found out. The altitude of the flyby is not so important, just find the altitude and latitude of Pe that will get your ship to the next encounter at the right time. The trick is that you cannot see more than two or so flybys ahead because of the digital limits of precision, so you have to trust that the planets will be where you need them at the right time. There was a tool called Slinger that would show you where all the planets would be at a specific time in the future, that was very useful because it could show me where both Kerbin and my ship would be when I needed to be at a future flyby periapsis and it was easy to adjust things to make the two match up. I don't think it has been updated past 1.0.5 though. It really taught me that the encounter time was the most important thing though.

It's fun to run the numbers to find a theoretical minimum. If you start in a 71x71km orbit around Kerbin, I believe an 842.2m/s boost is the absolute minimum to get you to an orbit that just touches the inner edge of Mun's SOI (= Kerbin apoapsis of 9571km). Let's then assume that some combination of flybys allows you to finally enter Mun's SOI with a Vsoi of 0m/s. (One might point out that you can't enter the SOI unless you are moving relative to it, so let's assume it's a number arbitrarily close to zero but not zero). Using the vis-a-vis equation and knowing Mun's SOI is 2429.56km in radius tells us that the resultant speed over Vcircular at 11km altitude would be 195.3m/s. So the absolute theoretical minimum for getting from a 71km Kerbin orbit to an 11km Mun orbit would be 842.2+195.3= 1037.5m/s. In practice course corrections, DSMs and the fact that you need some sideways motion at Mun's SOI to 'miss' it by 11km will always add to that but I cannot think of any way to beat that number. And if instead of entering an 11km orbit around Mun, one was to arrange to pass over the highest point on Mun (7.061 km) and do an explosive suicide burn at that periapsis it would take a 758.7m/s burn, so the theoretical minimum for going from a 71km Kerbin orbit to the Mun's surface is 1600.9 m/s. (Since the high point is near the pole its surface velocity is roughly zero.) Edit-actually it is cheaper to go for the 6000m mountain near the equator, the lower surface requires about 0.8m/s more for braking to zero, but the Mun's surface motion of 9.0 m/s give an overall benefit of 8.2m/s, so KLO to Mun surface for 1592.7m/s. And you are right, it is a lot of effort for relatively little gain to squeeze these last few m/s out of the mission.

Oh my, I did a mission very close to this some time ago when I was trying to get a Kerbal-X to the Mun's surface and back without refueling (which I demonstrated was impossible in 0.23.5). The thread is here, or you can shortcut to the Imgur album here. I tried to show every manuever with Mechjeb's dv counter so that others could copy the path. This mission had a parking orbit in LKO of 71.0x71.1km, I figure that gives about a 0.2m/s advantage over starting in an exact 71x71. Unfortunately I braked into a 6.3x8.8km Munar orbit, I went as low as safely practical to get that maximum Oberth effect for the landing. The key parameter is to note that the V-infinity when entering Mun's SOI was 129m/s, this cost 207.8m/s into my 6.3x8.8, I figure it would cost 206.3m/s to get from a Vsoi of 129m/s into a circular 11km orbit, so this mission cost a bit more than the one specified in your challenge would cost when using the same path. Summary of this method: LKO start boost: 845 m/s. Total of course corrections during first three Munar flybys: 3m/s Deep Space Manuever: 13m/s Braking into 6.3x8.8 Munar orbit: 208m/s. Total: 1069m/s. However it took 326 hours! I guess this cannot be a formal entry because of the low Munar orbit, but perhaps it can give people ideas. The only way I can think of to reduce it is to add another Munar flyby or two before braking into Munar orbit, but that would not save much and the course correction costs would make it iffy. I kind of don't want to fly this again because it took a lot of time to execute. Setting up that DSM is tricky as I note in the album. That mission continued to a Munar landing for 575m/s, 584 to get into a 9.3x9.3 orbit, (refuel), 205m/s Munar departure (heading out from Kerbin), 4m/s course corrections, to another DSM of 20m/s and on to Kerbin landing. 2457m/s for the whole LKO-Mun surface-Kerbin surface.

An impressive and interesting mission! I see what you are doing there, you are spitting a Juno-style DSM into two, as a result the first DSM is closer to the Sun then a lone one would be, and the 2nd DSM is further from the Sun then a lone one would be. The very interesting question is whether that saves total dV over doing just one DSM and one flyby of Kerbin. The further from the sun you are at your DSM the higher the multiplication effect, so does the higher-efficiency 2nd DSM exceed the loss of the lower efficiency 1st DSM? Using Mun to get to the 1st DSM makes it even more complex, because the slower you are going when you fly by Mun the bigger its addition to your velocity. This will not be simple to analyze. You are quite right that a low-dV path that requires nothing but Kerbin and Jool is available much more frequently than any path requiring other planets and so will be used more often. You have another interesting idea there, so far when doing multiple flybys of Kerbin or Kerbin/Mun we are increasing (or decreasing) the SMA of the ship's solar orbit, but one could instead keep the solar SMA the same by 'storing' the extra energy in solar orbit eccentricity, you would orbit Kerbol in 1 Kerbin year but you would encounter Kerbin at a high angle relative to its path around the sun, thus giving a higher VSOI at Kerbin. I would be interested to see how that works out, I've avoided it because I fear the final flyby that sends you to your destination would require too much of a turn angle around Kerbin, and that little planet wouldn't be able to swing it (just like it can't do my low-dV KEKKJ with only one K between Eve and Jool). I you're only swinging to a 3:2 orbit then it might be OK. We're finding all these excellent ways to get to Jool, but if you are going on to Eeloo then the windows are much more restrictive. At some point though someone is going to capture into orbit around Jool and then just wait until an optimal Jool-Eeloo window opens and use Tylo to get flung to Eeloo for free.

This is something of a necro thread, I started it two years ago, but heck, I'd still enjoy seeing and scoring entries so I declare it is still open. It is a very difficult challenge and so I never got a formal entry other than mine (though I did get Vector's spectacular method for using a Mun multi-flyby to enormously cut dV used) Now to your and Slashy's question- it is possible to use the rocket equation to compute dV expended once we know the start and end fuel masses of the craft, assuming no other mass change occurs on the ship. We have to be careful about RCS expenditures in particular- since Monoprop's Isp doesn't match the main engine's fuel we'll get distortions every time you tap the fine controls. On the other hand that will increase the apparent dV used so I'd say it can be ignored. Hmmm... I guess if only one specified kind of motor is used for the large maneuvers so we don't have mixed Isps, and we are careful to record masses before and after staging events then it is acceptable to not use Mechjeb or KER to record dV. And in the two years since my last entry I did manage to get from LKO to Jool for 914m/s using Vector's trick, so clearly someone could beat my 1934m/s entry here by about 100m/s, but it would not be easy .

It would theoretically be possible, but in practice it would be so difficult to set up and the gains from the Minmus flyby would be so small that I don't think it would be worth it. Minmus orbits way out of the plane of Mun and the planets and is almost never where it would need to be to be used for a flyby. I'd guess the maximum gain from a flyby of it would be <10m/s, and course corrections would eat that up. It would be an ultimate in panache though to fly by both moons on the way out from Kerbin...

Duna is small and a flyby of it can only save about 100m/s tops over a direct flight to Jool. On the other hand if you want to do just one flyby on the way to Jool then Duna is the best one to do. If you can do two flybys then Eve-Kerbin saves a lot though, and as shown above E-K-K is best of all.

Earth-Venus-Venus-Earth-Jupiter, or E-V-E-E-J involve a double flyby (also called a "direct-return" flyby) where you go by the same planet twice in a row. My Flyby Finder can't handle those and last time I checked TOT can't do it either, although he has been adding a lot of features to it so you should check. In addition (as noted by @Epox75 above) Cassini (and Galileo) made deep space maneuvers that are also tricky to plan. However it is possible to slowly find ballistic paths with double flybys using my LambertRSS spreadsheet and Flyby Finder together. I search for E-V-E paths, then for E-J paths (or E-J-Saturn), and try and find ones where both A) the Earth arrival from Venus and the Earth departure to Jupiter a separated by exactly two Earth years, and B) then Vinf in and Vinf out from Earth are nearly the same. Then I use Lambert to make sure the turning angle at Earth allows a flyby that is above the atmosphere. I've found two EVEEJ paths so far (obviously I was trying to simulate Galileo). Here's the best one: Leave Earth day 2530.3 with an ejection dV of 3772m/s from a 200x200km orbit. This is game Year 7 day 340 and Dec 4, 1957. Flyby Venus day 2703 (=Y8 d148) altitude 4930km. Flyby Earth day 3028 (=Y9 d108) altitude 6095km. Flyby Earth day 3757.7 (=Y11 d107) altitude 1804km. Reach Jupiter day 5185 (=Y15 d75). You can then flyby Jupiter at 171,000km and arrive at Saturn at day 11160 (=Y31 d210) but that is a ridiculously long flight. If you do this flight you'll notice that the Earth-Jupiter leg is not a good Hohmann, that is where a DSM between the Earth encounters would help. .

The search period and especially V at SOI are things I learned the hard way, by trying an initial search with a very wide search period and a very high VSOI and looking around until I find something. The primer I have in the first post of this thread can save you some time with its examples of successful searches. You can search more quickly by paying attention to synodic periods, for instance the synodic period between Kerbin and Eve is 680 Kerbin days (or 170 Earth days) so if you manage to find a path you like from Kerbin to Eve on K-day 100, then there should be another one around day 780. This is also a good search period- one synodic period. It is more complicated when more than 2 planets are involved but there are still 'quasi-synodic' periods between multiple planets where a good path repeats. For example 4 Kerbin/Eve synodic periods almost exactly equals 3 Kerbin/Duna synodic periods, so a good Kerbin-Eve-Duna path will often be repeated about 2720 K-days later. As for VSOI, if you are starting a completely new search I use 6000m/s for VSOI, this should be way more than anything needs. I'll usually get so many hits that the max_flybys_found is exceeded, but then I just sort the hits by start dV and look at the VSOI of the lowest ones and then reduce VSOI to something a little above that. Even trickier is figuring out when the 3rd, 4th, and 5th encounter search dates should start, since you have no idea whether there will be a low, fast possible route or a high, slow route, or both. So I set the earliest search dates to be only 10 days after the previous encounter's earliest search date, and the search periods for the later encounters to be ridiculously high, say 8000 days, and hope a 'hit' doesn't disappear in the gaps between search times. And of course proceed one encounter at a time, for instance if you want to find a Kerbin-Eve-Duna-Kerbin-Duna flight first find a Kerbin-Eve window, then narrow the search to that window and add Duna, then once you find that add Kerbin, and so on. Sorry if this answer is overkill, from your question it sounds like you've run into this stuff already. I don't have an easy answer. I sometimes think I should make a library of flyby windows. If you download the Lambert spreadsheet I did put some notes in there. EDIT: Sigh, I see I mixed up RSS and stock above, however most of it is the same. The spreadsheet LambertRSS has a page "synodic" that gives recommended V at SOI max values for each planet, in summary, starting from Earth and going to : Mercury: 8000m/s Venus: 3500m/s. If you're going to go Earth-Venus-Mars then 5500m/s is needed. Mars: 3500m/s Jupiter: 9500m/s Saturn: 11000m/s. I would never fly directly to anything past Saturn, a Jupiter flyby is always better IMHO. (Though the Jupiter-Uranus synodic period is 5047 days so it could be years until the next good window.)

Flybys are a great way to greatly reduce the dV needed to get to Jool with flybys. You can wing it when searching for the best times to execute a flyby, and if you are willing to orbit the sun several times in the process or make several deep-space maneuvers (DSM) you can usually find something better than a direct Kerbin-Jool flight, but there are two tools that can find the most efficient flybys for you. These are my Flyby Finder and Arrowstar's TOT. These find the specific times that you need to leave a planet and flyby each successive planet in order to go from K to J with only one large impulse, the Kerbin departure burn. (You will always need a few small adjustments along the way, but less than 100m/s should do it, and less than 20m/s with practice.) When setting up these flights the most important thing is to arrange the departure and each flyby to occur at the right time, if you do that the rest falls into place, for instance you adjust each flyby as you approach the planet to be in front of or behind the planet as needed to get the next encounter at the right time. Check out the flights below for details. There are numerous paths to get from Kerbin to Jool, here's a rundown. For comparison, going directly from K to J takes about 2000m/s when starting from a 75x75km Kerbin orbit. You can also go... K-Duna-J for about 1950m/s. Use my Flyby Finder or TOT to find these windows. Duna is too small to make much of a difference though. K-K-J using Juno's flight path for about 1550m/s. Goody1981 gives a link with clues on how to do this, Mad_Maelstrom made a great guide for this. K-Eve-K-Jool can be done for around 1300-1500m/s depending on the window. FF and TOT can find these. Here is an example of me using FF to execute a KEKJ. K-E-K-K-J can be done for as little as 1070m/s, or even 1011m/s if you fly by Mun on the way to Eve. Unfortunately this involves a double flyby of Kerbin and neither FF nor TOT can find these. I wrote a spreadsheet that can find them that is in the FF link, but it is a hard search and you might want to use one of the ones I show in my KEKKJ missions. And by using an exceedingly complicated multi-Mun flyby path I've managed to go from LKO to Jool orbit for 914m/s. This is getting pretty close to the theoretical limit of about 846m/s.

@Mad_Maelstrom made a little primer on flying a Juno-style mission in stock KSP. It is here. This way is less precise than TOT, but simpler to set up.

Zhetaan did the work here, Dres-Jool-Kerbin is the best route I know of. It sounds like it's going to be dramatically close, I don't know what orbit you are in (altitude and inclination) so I don't know how close to the 964m/s you can go and still get on the right path. And you'll surely need some course corrections. My first flyby advice is to time the Jool periapsis as close to the time FF recommends as possible. You have an intriguing idea- you could get from Dres to Jool for something in the low 700's, but then you wouldn't have enough energy to get thrown from Jool down to Kerbin. But if you flew by one of the big moons just right you could probably get the extra energy you'd need. Flyby Finder can't calculate that for you though.