Flight Question Moon to Earth, changing inclination

JayCee

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Question. I'm doing a return to Earth from the Moon, I want to transfer to a station in orbit around the earth, but it's at an inclination I cannot set up in IMFD at departure (it's too low below the reachable inclinations). The question is, when is the best time to change to align my plane with the least amount of dV? Do I change it whilst still outside Earth's strong SOI? And how would I do that with IMFD? Do I wait until I get close to earth and just circularize an orbit slightly below my target orbit and just use Sync Orbit? That option would probably cost me much more in dV in inserting orbit AND plane change (unless I can do both at the same time). Any pointers?
 

n72.75

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I think I want to try this myself before I give out any pointers.
 

francisdrake

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Not being familiar with the IMFD, I would at first brake into a highly elliptical orbit around Earth, with the Periapsis matching the orbit height of the target station.
Then, as far out as possible (near the Apoapsis of the highly elliptical orbit), I would make the orbital inclination alignment.
Inclination change is cheap on dV, if you are far out and slow.

After that I would go to sync orbits with the station.
 

n72.75

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So I'm pretty sure you want the two-plane option:
1680893996879.png
(the above is veeeeery rough and probably not a good example)

You will need to wait to a point in the Moons Orbit, until the moon is over the nodal line for the ISS, or in reality a few hours or so before it so you have time to get into orbit and get ready for your burn. The IMFD manual has some info on 2-plane course programs.
 

n72.75

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I should also note:

Use the surface launch program it will help you with heading.

You will need to perform a mid course burn or two.

When you do your aerobraking, you will have some control to fix (or mess up) relative inclination with your target.

Station's with higher inclinations are harder to get to both from a procedural standpoint, and from a DV standpoint.
 

JayCee

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So, you are using the Interplanetary Course program instead of Planet Approach in this instance? I'll give that a try.
 

JayCee

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Okay, so I did the Target Approach and Surface Launch in IMDB, once I got out of the Moon's SOI, I did a normal/antinormal burn (not at the node) to lower the RInc as much as I could, did a mid-course correction, did once for lowering of the RInc, and then once in the Earth SOI, I redid the Target Approach with two plane, it worked much better. Of course, I did a big burn to circularize as I got near the station, but the planar burn didn't hurt me nearly as bad as it would have before. Thanks for your help.
 
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