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brooklyn666

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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Check out the KSP_TOT tool in addon releases> tools. I've never seen a KSP tool more sophisticated.

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Be warned, though, that if you enter the target's SOI at high warp settings, your projected path may suddenly jump many kilometers from where you so carefully arranged it. Slow down to 10x or less for SOI transitions.

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