How do I get to the moons of other planets?

[Bluechance]

I'm trying to get to Gilly, but it seems like I can only achieve a polar orbit/capture and have to use tons of fuel adjusting the inclination. Is there any way I can get to planets with different inclinations like Eve and achieve an equatorial orbit without having to use my remaining fuel supply? Thanks.

Edited August 10, 2013 by Bluechance

[Geschosskopf]

The best way to get to a moon is to brake into a highly elliptical orbit of the main planet, so your apoapsis is out about as far as the moon you want to go to. It doesn't take much delat-V to circularize this at the far distance. Then just coast around until you've got the right phase angle (ahead or behind, depending on your orbit's diameter) to the moon. From there, just a mere fart of a burn will take you to the moon.

If the main planet has an atmosphere, by all means use it to aerobrake, so you don't have to spend as much fuel to get captured. Each aerobraking is a unique experience because it depends on the velocity you arrive with, plus the configuration of your ship. So have the mission control boffins back on Kerbin run simulations. That is, quicksave as soon as you enter the main planet's SOI. Then tweak your periapsis down into the atmosphere and see what you end up with. If you don't like it, load the quicksave, put the periapsis in a different place, and try again, repeat until you're happy.

[SRV Ron]

As you approach Gilly, but long before the capture, plan a correction burn to adjust the plane. It will then take very little fuel to get into a proper equatorial orbit. In fact, this can often be done with thrusters from such a distance. You have to set the map view to a planar view to plan such a burn. The maneuver has to be very precise so is best done with very low thrust for a short period of time.

Slingshot maneuvers around moons can also be used to change the orbital inclination as much as 90* to actually match their orbits using very little fuel. Again, that has to be done before being influenced by their gravity.

I had one equatorial encounter of a Jool moon that hit so precise that I nearly got a slingshot orbital capture. It completed with a two second lateral burn from my thrusters.

Edited August 9, 2013 by SRV Ron

[Tripzter]

That was the plan to my station back when it was 2-3 pieces and then i started getting lag. Since then i havent bothered docking to refuel. Instead i just toss a small fueling ship in orbit carrying the amount of fuel i need to refill my other ship. Probably will start making a fuel train with nothing but orange tanks with the left over fuel.

Edited August 9, 2013 by Tripzter

[Xiphos]

To use the least amount of fuel, adjust for an inclination change at the ascending or decending node on your way to the planet. (whichever one is the closest) Next, as soon as you enter the SOI of the planet, put a maneuver node down and you will notice it takes very LITTLE Dv to adjust orbital inclination as well as changing your Pe to do a nice aerobrake! Also, don't forget to quicksave (F5) when you enter the SOI incase you aerobrake too much!

[Motokid600]

So let's say I want to go to Laythe. I aero brake through Jool to bring my apoapsis to Laythe's orbit. Then what? The chances of Laythe being at the right spot at the aero brake are slim, no? So do I just wait in that eliptical orbit around Jool until Laythe gets to the right phase THEN make the transfer burn? What if the burn window occurs when my ship is at its apoapsis? Is it just a big waiting game?

[Geschosskopf]

So let's say I want to go to Laythe. I aero brake through Jool to bring my apoapsis to Laythe's orbit. Then what? The chances of Laythe being at the right spot at the aero brake are slim, no? So do I just wait in that eliptical orbit around Jool until Laythe gets to the right phase THEN make the transfer burn? What if the burn window occurs when my ship is at its apoapsis? Is it just a big waiting game?

The general plan is to aerobrake to get your Jool apoapsis out in the general vicinity of Laythe's orbit. So as you come out of your aerobrake, coast to your apoapsis then burn to raise your periapsis and circularize your orbit. This is because odds are, Laythe itself isn't anywhere near your Jool apoapsis. So now you ride around the circle until you achieve the same sort of phasing angle between your ship and Laythe as you'd use to transfer from Kerbin to Duna (if you're inside Laythe) or Eve (if you're outside Laythe). This won't take very long because moons have a short orbital period. Anyway, once you've phased up with Laythe, a tiny tiny burn will make you cross paths with it, after which you can aerobrake at Laythe to help establish your final orbit.

The time taken to phase up with the Laythe depends on the difference in your orbital velocities, which is greater the further apart your orbits are. But you want your orbit far from Jool so raising your periapsis is cheap on delta-V. So something like +/- 15-25% of Laythe's orbital radius out from Jool should work pretty well, as long as you don't get tangled up with one of the other moons.

[Geschosskopf]

I'm currently at work and my work computer can't access Imgur; say's it's porn. But I do have a post already with the pictures I wanted to show you to help explain all this. Here's the post:

http://forum.kerbalspaceprogram.com/showthread.php/43871-The-Kethane-Travelling-Circus-EPISODE-4-The-Duna-Package-Arrives?p=570657&viewfull=1#post570657

About 1/2way down this long post is a ship aerobraking at Duna to get to Ike. Doing just what I described above, apart from the pic of the spurious auto-capture to Ike. I think I had to wait about 3/4 of my orbit around Duna to catch up with Ike. Once I left Kerbin, I don't think I used more than 200-300m/s dV to get my Ike orbit, including mid-course tweak to intercept Duna (forgot to blip throttle prior to ejection burn), tweak to set periapsis for Duna aerobrake, burn to circularize Duna orbit, burn to transfer out to Ike, and burn to get captured by Ike.