How do you do prograde planet insertions correctly

[leocrumb]

The problem is always entering Minimus on a retrograde insertion.

There must be a simple way to work out how to enter in a prograde direction, but I cannot work it out. Every time is just a gamble

So how do I do it?

Edited July 25, 2015 by leocrumb

[Wemb]

The problem is always entering Minimus on a retrograde insertion.

There must be a simple way to work out how to enter in a prograde direction, but I cannot work it out. Every time is just a gamble

So how do I do it?

Perhaps I'm misunderstanding your question - but when you're planning your Minmus burn, you can right click and 'focus view' onto Minmus, zoom in and, assuming you've unlocked patched conics in the Tracking Station, see your end-path past minmus - so you can adjust your angle of entry by small adjustments to your burn then. Or by mid-course corrections.

Wemb

[leocrumb]

I dont think you understood the question. The actual direction in the map is not updated until you enter the planets SOE. I found this tutorial to tackle the problem but I dont understand him. http://forum.kerbalspaceprogram.com/threads/26928-Tutorial-Planetary-intercepts-or-how-to-orbit-in-the-right-direction

[NFunky]

Sounds like you may need to upgrade your tracking station. You really should be able to see your post encounter trajectory.

If your path is in front on minmus you will be traveling retrograde relative to minmus' orbit. That's a free return. If your course is behind it, you will be coming mostly toward minmus' prograde. I haven't checked, but I believe this is more efficient for a capture.

[Snark]

I dont think you understood the question. The actual direction in the map is not updated until you enter the planets SOE. I found this tutorial to tackle the problem but I dont understand him. http://forum.kerbalspaceprogram.com/threads/26928-Tutorial-Planetary-intercepts-or-how-to-orbit-in-the-right-direction

Actually, Wemb got it perfectly right-- it's a KSP feature that is easy to miss if you're new to the game.

Let's say you're in low Kerbin orbit, and you want to go to Minmus. You add a maneuver node, and so far everything looks good-- you can see that you're going to be hitting Minmus' SoI. But you don't know what your path relative to Minmus is (e.g. will it be prograde or retrograde) in this view.

So here's what you do:

You click on Minmus and choose "focus here". This does a very interesting thing: It locks the camera on Minmus, and it shows what your path will be through Minmus' SoI. It shows this even though you haven't entered yet. You can see exactly whether it's prograde, retrograde, etc.

And the cool thing is that even though you're focused on Minmus, your maneuver node over in low Kerbin orbit is still visible in the map view (if you rotate around until it's in view), and you can manipulate it as usual by pulling on the drag handles. So let's say you're focused on Minmus and see that oh darn, it's a retrograde approach. So all you do is start twiddling your maneuver node (while still focused on Minmus), until you've tweaked the orbit to just what you like.

When you're done, you can just hit the "backspace" key to un-focus from Minmus and re-focus on your ship.

It works like a charm, and is incredibly valuable for planning encounters.

(And yes, this only works if you've upgraded your tracking station so that patched conics are visible.)

[X-SR71]

A while back I posted in some other thread I find it to be rather difficult for a new player in career to get to the mun without both upgrades which allow for maneuver nodes and patched conics.

I'm not sure if these are hinted in the tutorial. I feel the game should hint that getting those upgrades are essential.

[Mic_n]

Take a timeout and stop to think about what you're actually trying to do.

You're pushing the orbit of your craft out to enter the gravity well of another body out there. That gravity well is going to influence the shape of your orbit, pulling it in towards the centre.

So.. assuming that by "prograde" you're meaning orbiting towards the east, then it's just a matter of making sure you enter the SOI in that direction.. IE that you have the body "on your left". If the center of that gravity well is "on your left", then your orbit will be deflected in towards it - 'to the left'. So if you look at your full orbital path once it's back out of that SOI, it will be bent "inwards". If you're passing by with it on the other side, your orbit will be bent "out".

So.. which way does your 'exit' orbit deviate? Does it tighten, or open out?

[Kryxal]

I'd get Mechjeb or PreciseNode so you can easily fiddle with the nodes ... I usually find the prograde and retrograde handles poorly placed when looking at the moons.

[leocrumb]

Perfect, Thankyou

Actually, Wemb got it perfectly right-- it's a KSP feature that is easy to miss if you're new to the game.

Let's say you're in low Kerbin orbit, and you want to go to Minmus. You add a maneuver node, and so far everything looks good-- you can see that you're going to be hitting Minmus' SoI. But you don't know what your path relative to Minmus is (e.g. will it be prograde or retrograde) in this view.

So here's what you do:

You click on Minmus and choose "focus here". This does a very interesting thing: It locks the camera on Minmus, and it shows what your path will be through Minmus' SoI. It shows this even though you haven't entered yet. You can see exactly whether it's prograde, retrograde, etc.

And the cool thing is that even though you're focused on Minmus, your maneuver node over in low Kerbin orbit is still visible in the map view (if you rotate around until it's in view), and you can manipulate it as usual by pulling on the drag handles. So let's say you're focused on Minmus and see that oh darn, it's a retrograde approach. So all you do is start twiddling your maneuver node (while still focused on Minmus), until you've tweaked the orbit to just what you like.

When you're done, you can just hit the "backspace" key to un-focus from Minmus and re-focus on your ship.

It works like a charm, and is incredibly valuable for planning encounters.

(And yes, this only works if you've upgraded your tracking station so that patched conics are visible.)

[Space Peanut]

A while back I posted in some other thread I find it to be rather difficult for a new player in career to get to the mun without both upgrades which allow for maneuver nodes and patched conics.

I'm not sure if these are hinted in the tutorial. I feel the game should hint that getting those upgrades are essential.

I really loved the "flying by the seat of your pants" feel of trying to get to the Mun without nodes but you probably right here. New player would bumble along, get nodes and think "what the hell are these for???" and not really appreciate how important they are. Maybe the game needs better in-game manual to explain this kind of thing?

[Sharpy]

And the cool thing is that even though you're focused on Minmus, your maneuver node over in low Kerbin orbit is still visible in the map view (if you rotate around until it's in view), and you can manipulate it as usual by pulling on the drag handles. So let's say you're focused on Minmus and see that oh darn, it's a retrograde approach. So all you do is start twiddling your maneuver node (while still focused on Minmus), until you've tweaked the orbit to just what you like.

One note: Kerbin is far enough from Minmus that getting a reasonable encounter on the right side, with the right inclination and close enough to utilize Oberth effect while braking - and most of all *executing* that maneuver is about impossible. Differences of order of 0.01m/s can totally shift the side you're meeting Minmus. So, from Kerbin just get any half-decent encounter, and then execute a correction maneuver perfecting your trajectory when roughly halfway to Minmus. The closer to Kerbin you do it the less precise it will be but cost less delta-V. The closer to Minmus the more precise you can make it, but the more fuel you'll spend.