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Changing inclination when on trajectory with encounter?


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I have 2 ships that are on a trajectory to Eve. For both, I accelerated from LKO (Low Kerbin Orbit) until I got an encounter with Eve. It shows a periapsis now.

It seems to me that I should match the orbital plane as soon as possible, so that I can also do the fine-tuning of the encounter early. But the ascending/descending nodes do not show, because my trajectory has en encounter with Eve (as soon as I accelerate a little and lose the Eve-encounter, they show up).

How do you guys do this? I would rather leave the Kerbin system on a trajectory that I know will encounter Eve, rather than just eyeballing it, fix the orbital plane, and only then aim for Eve properly. 

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I just eyeball it really. Hit tab to zoom in on the body I will have the encounter with. Setting up a node somewhere along the trajectory, ab-ing to zoom in on the body, and fiddle with the node until my Mk I eyeball is happy. If you target the body beforehand, you will get the AN and DN to show up on your orbital trajectory. Sometimes that's where you want to do the burn, other times not. When is to me a lot of fiddling with the node until the AN/DN reads about 0 for the least amount of dv. Lots of eyeballing in other words.

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Is it possible to hit an equatorial orbit on Eve on the first approach? My ships are still far away, but no matter in which direction I adjust my velocity (pro/retrograde, normal/antinormal or radial in/out), it seems I cannot get my periapsis with Eve to move near its equator, although I can make it more polar if I want. The problem seems to be that I approach Eve from below its orbital plane. 

Most tutorials for getting to Eve seem to be content to just hit Eve and land... but I want to attempt an Eve landing and take-off (a manned Kerballed mission), so I will have a 2nd ship in orbit with more fuel to get the guys home. It's important to get my ships on a practical orbit around Eve for a rendezvous later on. Equatorial seems the most practical, except that I cannot figure out how to do it! 

*shakes fist angrily at Kerbol*

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57 minutes ago, Magzimum said:

Is it possible to hit an equatorial orbit on Eve on the first approach?

Yes, if you have zero relative inclination to Eve's orbit. 

What I would do is make a very small burn so that you lose your Eve encounter and the ascending/descending nodes show up. Then put a maneuver node right on whichever node you come to next. Use that maneuver to do two things: get the relative inclination to zero and restore your encounter (and set your PE where you want it). 

After that burn, as you get a little closer, you can make small correction burns to fine tune your Eve orbit. 

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17 minutes ago, FullMetalMachinist said:

What I would do is make a very small burn so that you lose your Eve encounter and the ascending/descending nodes show up.

That is what I am doing now, but feels wrong to waste fuel on that (even if it is just a few m/s). Was hoping that there is another (more elegant) method!

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2 minutes ago, Magzimum said:

That is what I am doing now, but feels wrong to waste fuel on that (even if it is just a few m/s). Was hoping that there is another (more elegant) method!

Well you could get an information mod like KER or Mechjeb, those both have a "time to AN/DN" function. Then just make a node that is that far ahead of you. 

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4 hours ago, Magzimum said:

It seems to me that I should match the orbital plane as soon as possible, so that I can also do the fine-tuning of the encounter early. But the ascending/descending nodes do not show, because my trajectory has en encounter with Eve (as soon as I accelerate a little and lose the Eve-encounter, they show up).

How do you guys do this? I would rather leave the Kerbin system on a trajectory that I know will encounter Eve, rather than just eyeballing it, fix the orbital plane, and only then aim for Eve properly. 

Usually, Kerbin is outside of Eve's orbital plane (and thus Eve's equatorial plane which is the same in KSP) so your starting point is outside the target plane.  So you will have some time traveling into that plane before you can turn to match it.  In order to arrive at your destination, and also be moving in your desired direction, you need some mid-course correction.

1 hour ago, Magzimum said:

That is what I am doing now, but feels wrong to waste fuel on that (even if it is just a few m/s). Was hoping that there is another (more elegant) method!

Opinions on what is most elegant will differ, but I think you might like to leave Kerbin on a path that will pass over Eve's north pole, just far enough above that an AN mark appears a bit before the close-approach, and turn at the AN into Eve's plane (along the lines of what f.m.m suggested).

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The main trick is to leave when your origin planet is at the AN relative to the target planet; then you launch into 6-degree inclination and you're good.

Otherwise, you will arrive at the AN, and you can combine the capture burn with the inclination change.

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