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How to predict inbound inclination for interplanetary transfers


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Hi folks. Forgive me if this is a silly question, but I'm rather new to KSP after using Orbiter for many years. Anyway, my question is, how to I predict my inbound inclination when arriving at my destination body before I enter its SOI? Let's say I want to arrive at Duna in a 20 degree inclined orbit without having to do a major plane change burn. It seems that Mechjeb and Engineer have no way of doing this, unless I'm missing something. The only way I can see to do it now is to guess based on the trajectory in map view, which is about as precise as not knowing at all.

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if you set CONIC_PATCH_DRAW_MODE = 0 (Mech jeb can do this in the maneuver node editor) it will draw your path relative bodies. If you also change CONIC_PATCH_LIMIT to something higher than 3 it will also plot more SOI changes. Both of these are in the Settings file.

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if you set CONIC_PATCH_DRAW_MODE = 0 (Mech jeb can do this in the maneuver node editor) it will draw your path relative bodies. If you also change CONIC_PATCH_LIMIT to something higher than 3 it will also plot more SOI changes. Both of these are in the Settings file.

Thanks. That's helpful, but it didn't quite answer my question. What I want to know is, for example, when I'm in LKO planning my ejection burn to the Mun, I want to know what burn parameters will result in X inclination upon Munar orbital insertion, and if I were to perform a mid-course correction, what burn I would need to perform to establish a Munar orbit with X inclination

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If you're wiling to eyeball your arrival inclination, as Taki17 mentions, setting CONIC_PATCH_DRAW_MODE = 0 in the settings.cfg will let you do that.

When you do this, instead of getting weird squiggly lines of dubious value when your future path passes through a world's SOI, the patch will be drawn in the frame of reference of the object (So it looks like a normal hyperbola) and at the current position of the object (So you can hit Tab a few times and center on it for a really close view.)

screenshot259.png

The result being that, weeks or months before you reach your destination, you can pop a maneuver node a few hours ahead of your ship, run your time accel up to 5x so things stop jumping around, center the map screen on your destination, and spend a few minutes finessing the maneuver node that will move your periapse and arrival trajectory close to where you want them, and spend maybe a 10-15 m/s of delta-V doing it.

From there, it's a matter of just sighting along the plane of your in-SOI patch to get a good idea of your arrival inclination.

If you want to know your /exact/ inclination on arrival before you enter the SOI, Protractor will show you that, but last I checked, it only checks patches on the path your spacecraft is currently on, not paths generated by maneuver nodes.

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Doesn't look like a very fuel efficient way to me if you're doing plane changes that close to Eve. I think OP here is more interested in a direct off-plane transfer as one would do in Orbiter with the help of IMFD.

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