How to perform a plane change maneuver.

[VincentMcConnell]

I\'m sure many people here have wrestled with the annoyance of having a severely tilted orbit that allows for a very difficult return from the Mun or a bad landing site. My guide will teach you how to fix this pathetic orbit and establish an equatorial orbit that is more desirable in *most* situations.

KNOWING YOUR DIRECTION OF TRAVEL

It\'s very important to actually know *which* way you\'re moving for this maneuver to work. If you\'re heading south, or Southeast, southwest, etc. you\'ll want to know exactly when you\'ll cross the equator or intersect your desired point of orbit. If you want to make equatorial orbit, the easiest way to describe this maneuver, you\'ll want to wait until you are traveling south or north towards the Equator.

BURNING AT THE CORRECT TIME

This kind of procedure requires a burn that is not usually used. Most times, we are accustomed to a prograde or retrograde burn. Plane change maneuvers require a burn that is focused at South or North. Both of these are directly in between your prograde and retrograde indicators. North is characterized by an orange line and the letter 'N' on your navball, while south is left blank. In an orbit, both of these will likely be along the white line that is your artificial horizon on your navball. If moving south, you want to wait until you cross your desired point of orbit and starting thrusting at full throttle *NORTH. If moving North, thrust full throttle at south. In your map, you will notice that your orbit has now swiftly tilted back from this topsy-turvy path onto a cleaner and more direct orbit around the equator.

For the sake of visual learners, I have included a little diagram.

[purple100]

So, if you\'re on the green line headed south, is that a burn along your 'orbit normal' vector?

If it is, that means you can use MechJeb to keep yourself aligned properly.

[semininja]

Yes, MechJeb is great for plane changes. The normal/anti-normal setting is exactly what you want.

[VincentMcConnell]

So, if you\'re on the green line headed south, is that a burn along your 'orbit normal' vector?

If it is, that means you can use MechJeb to keep yourself aligned properly.

Yes. If headed south, you\'d burn normal.

[MFToast]

Thanks for these, vincent. It\'s really helped me understand orbits in all three dimensions rather than just a flat plane. I managed a 600m rendezvous, that\'s a big ass step for me.

[VincentMcConnell]

Thanks for these, vincent. It\'s really helped me understand orbits in all three dimensions rather than just a flat plane. I managed a 600m rendezvous, that\'s a big ass step for me.

Rendezvous at 600meters is pretty close for a first run. Good job! My first Rendezvous was a few kilometers apart (if that could even be called rendezvous) and the spacecraft zoomed by overhead. My second was successful around the Mun, but I figure that was mostly luck lol.

[Awaras]

I have found that once you are closer than 3-4 km to your target and you have matched orbital planes and orbits as best you can, simply slowly thrusting towards the target with RCS and watching and correcting for drift it is enough for a successful rendezvous.

[VincentMcConnell]

I have found that once you are closer than 3-4 km to your target and you have matched orbital planes and orbits as best you can, simply slowly thrusting towards the target with RCS and watching and correcting for drift it is enough for a successful rendezvous.

That\'s correct. Much like landing on the Mun, that final approach comes down to fine controlling with the RCS and piloting skill. Most of it can be done by eye, though.

[purple100]

Yay! I used this technique to re-align my orbit around Mun and land a craft close to my previous expeditions! Glad I learned how to do this.