Multiple transfers to a destination?

[NeverEnoughFuel!!]

Well as the title says, how to use/create proper "slingshot" maneuver? Is it possible? Let's say I want to go to Eloo by Jool to save some delta V... how would I get all the data needed for such a maneuver, i.e. phased angles, proper date when those two planets are aligned for such maneuver... as far as I can see all of the mods/plugins are limited to one destination at a time... please don't say MechJeb... what's the point of flying if the computer does it for you...

[DrLicor]

For calculation those manouvers there are a few links

http://ksp.olex.biz/

https://alexmoon.github.io/ksp/

 

the last one is the one you need I think  

[Streetwind]

Those don't really help that much IMHO.

In order to use a slingshot maneuver, you need to have a window to your 'sling' planet at the same time that planet has a window to your destination. Even with the ability to get each window calculated for you automatically, it's still really hard to find a timing where the two results actually occur on compatible dates.

There are proper computer tools for this, but I guess, if manual is the way you want to go... You could try to eyeball it ingame based on the phase angles, as unreliable as that is. Biggest problem: you need to mentally "calculate forward" how the phase angles between sling and destination will look like in the future, at the moment of your arrival at the sling planet.

 

Edited November 7, 2016 by Streetwind
I'm done editing now, for realz. Promise.

[Sharpy]

 

[Plusck]

The way I do it, using exclusively https://alexmoon.github.io/ksp/:

• First find out roughly how much time and dv is needed to go from one planet to the next, only putting an "insertion burn" in for the last planet:
• So from Kerbin to Jool needs about 1300-1700 days, with very little dv difference, really, about 100 m/s or so at the edges.
• And from Jool to Eeloo needs about 1300-1700 days too (how strange),
• Then start with your final transfer (so from Jool to Eeloo) and see how much leeway you have for departure: you can leave between the start of year 9 and halfway through year 10...
• And work backwards to see when you can leave to arrive at Jool at that time: and you find you have to leave in year 6 day 385 or so to get to Jool in mid-year 10. Or you can leave earlier (year 5 day 365 or so) and take longer to get there.
• Or start with the transfer which has the least leeway, and work forwards and backwards from there.

I managed to do a 6-body route for a contract like this. It was relatively painless, all things considered.

Apart from that, I don't think you need to worry too much about phase angles and suchlike for the slingshot maneuvre as such. As long as you intercept, you can slingshot. The important part is the fine-tuning so that you enter the SOI and leave it going the right way, to maximise your orbital energy.

[NeverEnoughFuel!!]

6 hours ago, Streetwind said:

Those don't really help that much IMHO.

In order to use a slingshot maneuver, you need to have a window to your 'sling' planet at the same time that planet has a window to your destination. Even with the ability to get each window calculated for you automatically, it's still really hard to find a timing where the two results actually occur on compatible dates.

There are proper computer tools for this, but I guess, if manual is the way you want to go... You could try to eyeball it ingame based on the phase angles, as unreliable as that is. Biggest problem: you need to mentally "calculate forward" how the phase angles between sling and destination will look like in the future, at the moment of your arrival at the sling planet.

 

I agree... this flyby finder should be part of let's say Protractor or KER or TWP or separate mod in-game ... this way... I won't say it's useless because it isn't... but let's say I'm not THAT fanatical... regarding eyeballing... lol... I can barely hit a planet with combination of KER, KAC and TWP at the same time since they all give different predictions and calculations and I'm always either too late or too early and planned delta V is never accurate so my only weapon against this is redundancy in form of extra fuel/mass... oh well...