How To Transfer To Another Planet?

[Popestar]

I have gotten quite skilled at doing transfers to Mun and Minmus, and now I'm ready to try my hand at going interplanetary.  I don't want to land just yet, but perhaps put a satellite in orbit, collect some science, and then zip back home.  My problem is that MechJeb isn't creating and executing nodes, telling me in nice yellow script that my inclination is off, or that controls are locked, or that I have to select the Sun when I'm in some kind of orbit other than Kerbin's SOI.  And because I've never done this before, I'm stuck.  I'm just not sure how to accomplish transferring to another planet.

I tried searching for a tutorial, but all I'm finding are dV spreadsheets and transfer window calculators.  What I need is a how-to on actually getting to another planet, step by step.  The calculators are fine, but they aren't telling me how to use that information to actually do what I need to do.  I can build a rocket; I can get to Minmus.  But how do I actually get to Duna, or Eve, or Gilly, or one of the other rocks out there?

[Spricigo]

Well, any tutorial worth its salt will assume knowledge of more basic concepts(basic orbital mechanics, how to make a maneuver node, etc), so it is no surprise you are only getting resources that focus on the critical part of it (transfer angle, deltaV requirements, etc).

Anyways, 

1 hour ago, Popestar said:

My problem is that MechJeb isn't creating and executing nodes, telling me in nice yellow script that my inclination is off, 

The calculation become unreliable from inclined orbits, so MechJeb will not even try if you happen to be in a inclined orbit. 

1 hour ago, Popestar said:

or that controls are locked,

No idea. assume to be some MechJeb setting I'm not familiar with.

1 hour ago, Popestar said:

or that I have to select the Sun when I'm in some kind of orbit other than Kerbin's SOI.

Should be some [parent body] selection somewhere in the mechJeb setting.

 

Back to the "how to interplanetary" problem, transfer between Min and Minmus are good for practice since it involves all the aspect you will find in a typical interplanetary transfer. A quick search returned this tutorial:

 

[Popestar]

[snip]

Your response isn't helpful.  [snip]  I am simply asking for a tutorial on interplanetary transfers.  Not Mun to Minmus; I can do that.  They aren't that easy going out to the distance of Duna or beyond. [snip]

Edited February 14, 2021 by Snark
Redacted by moderator

[HebaruSan]

2 hours ago, Popestar said:

all I'm finding are dV spreadsheets and transfer window calculators.  What I need is a how-to on actually getting to another planet, step by step.

I haven't used MechJeb (though I have borrowed code from it), so these are the stock-only instructions:

1. Identify the transfer window during which you will depart, using the spreadsheets and calculators you've already found
2. Time warp to the window (within a few days or so)
3. Set your target in the map view
4. Set up a maneuver node going in approximately the right direction (planet-prograde for outer planets, planet-retrograde for inner planets)
5. Dial in the delta V specified on the spreadsheets and calculators
6. Zoom out to solar orbit; after you escape Kerbin, you should see a transfer orbit that takes you at least somewhat close to your destination, and the close approach markers should be present
7. Fine tune the maneuver till you get an encounter

A whole world of complications can open up at each of these steps, but I don't know which ones you will encounter, so please ask follow-up questions as needed.

Edited February 14, 2021 by HebaruSan

[Gargamel]

1 hour ago, Popestar said:

Your response isn't helpful. [snip]  I am simply asking for a tutorial on interplanetary transfers.  Not Mun to Minmus; I can do that.

It is helpful, if you can do a Mun to Minmus direct, then you can do a Kerbin to [any other planet].  It's the same thing.   It's two bodies orbiting a larger parent object, and you are trying to transfer between them directly without entering a non-encountering orbit around the parent body.    The only real difference is the time scale, and of course a bit more dV.  A Mun to Minmus takes ~18 days or so, while a Kerbin to Duna takes a few months?  I forget.  

If you look in the tutorials section of the forums, you will find a number of them on how to setup a interplanetary transfer manually.  The transfer window planners tutorials should include some instructions on how to use them.  Perhaps you could link them so we could explain them better?

As for mechjeb, it's very quite simple.

Pick your target, then open the interplanetary window in the maneuver planner (I believe that's the tab it's under).   Pick the Porkchop simulation, and let it calculate the windows.   Looking at the graph, click on the location that selects the optimum dV and departure/arrival times for your mission.    And then press execute.   Same way you would do a mechjeb Mun to Minmus transfer. 

[Snark]

Some content has been removed and/or redacted due to people making personal remarks, which is never appropriate (see forum rule 2.2.d).

Folks, let's please remember that we're all pals here and that the purpose of the forum is for players to help each other.  Which is what's going on in this thread:  someone has a gameplay question, and other people who are trying to help are offering suggestions.

Whether you find someone else's comments helpful or not, it's never appropriate to get angry to the point of making personal remarks.  Keep it civil, please.

Thank you for your understanding.

[king of nowhere]

3 hours ago, Popestar said:

[snip]

Your response isn't helpful.  [snip]  I am simply asking for a tutorial on interplanetary transfers.  Not Mun to Minmus; I can do that.  They aren't that easy going out to the distance of Duna or beyond. [snip]

as others said, a mun to minmus transfer is basically the same as an interplanetary transfer.

how do you go about it? you are around mun, you will make a prograde burn in a point of the orbit that will result in your vessel leaving tangential to mun's orbit. your burn will be powerful enough to raise your kerbin apoapsis all the way to minmus. and you may have to do a plane change somewhere along the way. and of course you must pick mun and minmus when they are in the right positions, or the manuever becomes much more expensive.

well, interplanetary is the same. you can try with duna or with jool, they are the easiest to reach. use alexmoon planner to find a transfer window. when the time is right, plan a manuever node so that you will leave tangential to kerbin's orbit. have that burn be powerful enough to raise your kerbol apoapsis enough to reach the other planet. tweak a bit deltaV and exact position of manuever node to ensure an efficient transfer. now, at this point you probably didn't get an intercept yet. but you must be close. now, plan a plane change too. you can add a normal/antinormal component to your burn, or you can set another burn at the orbital nodes, which by now will be highlighted. the first is generally cheaper, the second is always easier.

anyway, when your planned orbit is touching your target's orbit, and your plane change node is also nearby, then you should get a close approach marker. from there, it's easier.

when you get some practice, you will also be able to eyball where your target planet will be, and make your manuever accordingly, skipping the part with the close approach marker. this will also help you with more complex manuevers

it's late now. if you want, tomorrow i can post pictures

Edited February 14, 2021 by king of nowhere

[Popestar]

Close the thread please.  I no longer wish to have this answered by the community.