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3 questions on Maneuver Nodes.


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I have no idea how to use the maneuver nodes to do transfer burns, can someone help?

whenever I aim at the target prograde marker with the moon as my target I always end up deorbiting my self also. How can I make maneuvers at something other than AP and PE?

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I have no idea how to use the maneuver nodes to do transfer burns, can someone help?

whenever I aim at the target prograde marker with the moon as my target I always end up deorbiting my self also. How can I make maneuvers at something other than AP and PE?

Go to map mode. Click on your orbit to add a maneuver node, then set it as desired using the drag handles. Leave map mode. Aim your ship at the blue marker on the horizon ball and start the burn about half the duration before the burn start time.

In general you don't want to burn straight at something (using the target markers) in order to make a transfer burn. You instead want to modify your own orbit to intersect the target's.

http://wiki.kerbalspaceprogram.com/wiki/Navball

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Thanks for the help, I was aiming for the pink markers to change my orbits inclination relative to the Mün, even though the moon is at 0.0 relative inc. I'll try manually setting up a node instead of just following the pink markers for the targets.

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I'll try manually setting up a node instead of just following the pink markers for the targets.

There might be a method to use the target markers to help make a transfer burn, but I'm not aware of it.

Also be aware that manually setting up maneuver nodes sometimes takes some trial and error; once you've done a couple of transfers to a particular body from a given orbit you can almost always eyeball a decent location for a node on the first try, even if it's not the best place to start your transfer burn (point being, it gets easier :)). This is one of the reasons I make all my Mun transfers from a 100km Kerbin circular orbit.

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Thanks for the help, I was aiming for the pink markers to change my orbits inclination relative to the Mün, even though the moon is at 0.0 relative inc. I'll try manually setting up a node instead of just following the pink markers for the targets.

Correct me if I'm wrong but given an equatorial orbit there is no need for using the "pink markers" as these would only change your orbit inclination. AFAIK you should use the prograde marker to to extend your orbit until it falls within the Mün SOI.

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I'm not exactly sure what you're describing, so forgive me if I'm pointing out the obvious, but when flying by maneuver nodes, the only marker you ever need to aim for is the blue maneuver-prograde one. The relative positions of the other markers are already accounted for by the maneuver system.

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Another helpful hint is, when extending your prograde node, try to make it so that it will intersect the Mün's orbit about a quarter of the way ahead of it. So, if the Mün is at your 3 o'clock, you should try to aim towards 12 o'clock.

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Make a maneuver node so that your apoapsis marker intersects the Mun' s orbit. Assuming a zero inclination, circular orbit, start dragging that around by clicking the central circle and holding, then dragging it around your orbit. At some point, you should get a Munar encounter!

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Yes, it's true that if you are sticking to maneuvers only, you only need to use the blue marker.

The way you describe it to me, pulling prograde yet still deorbiting yourself, sounds a lot to me like you have your control core facing the opposite way, 180 degrees from where it needs to be. A quick way to check is to get into a stable orbit, turn retrograde. Note how the ground moves below you. If you're head first, not engine first, your control core is 180 degrees out of whack. c:

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quick question, slightly on the same topic, are there keyboard keys you can use to fine tune setting the maneuver nodes? Sometime using the click and drag pointers on the maneuver node it is difficult to make small correction.

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Go to map mode. Click on your orbit to add a maneuver node, then set it as desired using the drag handles. Leave map mode. Aim your ship at the blue marker on the horizon ball and start the burn about half the duration before the burn start time.

In general you don't want to burn straight at something (using the target markers) in order to make a transfer burn. You instead want to modify your own orbit to intersect the target's.

http://wiki.kerbalspaceprogram.com/wiki/Navball

But how do you adjust it precisely? I always find it goes crazily off somewhere, and can't be dragged back easily.

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But how do you adjust it precisely?

Gently. Use the radial (blue) drag handles to fine-tune circular orbits and realize that there will always be some margin of error.

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A couple of questions...

1. Have you docked to a craft?

2. Are you controlling from the proper module? For instance, you could be burning towards your prograde marker, problem is you're controlling from a docking port or module facing your engines, which in turn makes you burn off all of your orbital velocity hence you falling down.

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When your ship is pointed at the pink marker, it is pointed directly at the target. Unlike all the other markers on the Navball, it's not a velocity marker; it's a position marker. It's very useful for orbital rendezvous, but is not very useful for transferring to another celestial body, because both your vessel and the other body are travelling curved paths.

To hit the Mun from a circular LKO, you'll want to start your burn when the Mun is about 90 degrees east of your current position. (I always go to map view, rotate it until I'm looking down (south) at Kerbin, turn the screen so the Mun is directly to the right of Kerbin, then put my maneuvering node directly below Kerbin.) You actually don't need a maneuvering node; if you start your burn there, you'll enter the Mun's SOI, but the maneuvering node lets you fine tune your approach.

For precise adjustment of maneuvering nodes without gnashing your teeth in frustration I recommend installing these two plug-ins:

http://www.reddit.com/r/KerbalSpaceProgram/comments/1c3cba/plugin_bettermaneuvernodes_v01_control_maneuver/

http://kerbalspaceprogram.com/maneuver-node-improvement/

- The first allows you to adjust the maneuvering nodes using the Num-pad keys, and switch to fine control using Capslock and Alt.

- The second allows you to select your last selected maneuvering node using the 'O' key (very useful) and has textboxes for entry of absolute delta-V's for each axis.

Edited by Mr Shifty
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But how do you adjust it precisely? I always find it goes crazily off somewhere, and can't be dragged back easily.

If you don't want to use any of the suggested mods, you can 'push' the opposite control instead of 'pulling' the one you want. That will give you a little more fine control.

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But how do you adjust it precisely? I always find it goes crazily off somewhere, and can't be dragged back easily.

The handles are not very precise, IMHO. But the more you pull the faster it goes. You can also push in on them rather than switch to the opposite handle.

The whole process is pretty simple. Ideally, get yourself in a circular orbit in the same plane as the Mun, which is 0 degrees. Use the grab handles at any point in your orbit and drag it prograde, that's the yellow one in the same direction as your orbit, until the ellipse of your projected orbit touches the Mun's orbit. Then grab the ring of the node and drag it around your orbit until you get an encounter. You'll know it when it happens. Your orbit path will get all wonky looking and there'll be a little tag on it that mentions the encounter. On your nav-ball you'll get a blue crosshair and a yellow delta-v bar. point your craft at the blue crosshair and burn your engine until the yellow bar goes down to zero. It should tell you how long the burn is at max throttle. You should time your burn so half of it is before the node and half after, but don't worry too much about getting that precise, especially if it's a short burn. Make sure to delete the node after it's done. You may need to make a correction burn, and usually the earlier you do that, the cheaper it is.

Oddly enough, when this is done right, you're generally pointing at the Mun when it happens, however, you can't just point at the moon at any point in your orbit and have a go.

Edited by DChurchill
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