Trouble with Docking Tutorial

[CaptainApollo]

Hello everyone! I am thinking of making a space station soon on my main career mode profile, and I went to do the in-game Docking Tutorial. All went well so far; the orbital inclination adjustment and everything else, but then I ran into a bit of trouble. When you have to intercept your orbit with the other craft's, I cannot seem to make the orbital difference less than 5 km, like Gene Kerman says. I have been trying for almost half an hour now and cannot get it right. Are there any tips or good ways to do this? Thank you!

[jkool702]

This is what I do:

(assumes you are already within a few km range of the target)

1) target whatever craft youre trying to dock with

2) change the navball so that it is in target mode (click where it says "orbit" or "surface")

3) burn retrograde to kill off any relatve speed between yourself and the target

4) use the navball to travel directly towards the target (pink circle with the dot in the middle)

5) when you get close to the target switch to retrograde to kill off any relative speed between yourself and the target (again)

6) repeat steps 4 and 5 until you are sufficiently close to the target

7) use rcs thrusters to make the final alignments once you are within about 100m (a little tricky but gets easier with practice)

Hope this helps!

[CaptainApollo]

Thank you Jkool, this will help me in the future! But I am talking about how do I intercept the other target, as in how do I get a few km range of the target. Thanks.

[jkool702]

Ah. I use maneuver nodes.

Again set the target first. Get in an orbit either above of below the target in roughly the same shape, and then use a maneuver node (prograde or retrograde, depending on your orbit relative to the target). When your projected path crosses the targets path you will see 2 arrows indicating you closest approach to the target. play around with the maneuver node (move left / right, change speed slightly) until the arrows are aligned. Note that you may need to make one or more revolutions of your orbit to find the correct path, but eventually you will find a maneuver that gets you within a few km of the target. Then you can follow my previous post.

If you don't have maneuver nodes you might have to wait until you unlock them, cause without them its pretty much impossible.

[CaptainApollo]

This seems to be the best way, and indeed I do have maneuver nodes unlocked, thankfully! I will do this tomorrow and hopefully do it successfully, thank you!

[Reactordrone]

if you follow the docking tutorial you may need to advance your node a few orbits to get a close intercept in one burn. Usually you can just raise your apoapsis to match the target orbit and then orbit until the targets predicted location overshoots and then raise the periapsis until the distance to target winds back to a close approach, you should be able to get it within a few hundred metres. On the next orbit you just have cancel most of your relative velocity and you're into the docking phase.

[CaptainApollo]

So I make my orbit higher? I may try that.

[Sawyer7as]

There's a docking tutorial?

[justidutch]

I am actually quite happy to get to within 5km. Heck, anything less than 10km and I feel the docking procedure is fine. The closer you can get your initial rendezvous the better, but the principles are all the same no matter how far away you begin. In fact, you'll probably learn more by starting 5km out than 1km.

[jkool702]

How close I try to get depends on what body I'm orbiting. Something small like Minimus or Gilly I can usually pull off <1km no problem. Something larger like Kerbin I feel fine with 5-10km. If I'm trying to rendezvous with something orbiting Kerbol Im usually pleased to get within 100 Km lol.

[Prepper-Jack]

Easy intercept in low orbit:

1) Target said vessel and get into a similar orbit with roughly matching peri/apoapsis.

2) Burn Normal/Anti-Normal near ascending/descending nodes to get into roughly the same inclination as your target.

3) Directly after passing the first intercept point, burn prograde until the target position and intercept point are on top of each other.

4) Time warp to a little before that point, make sure your target is "target" (click where it usually says orbit or surface), and burn retrograde until this speed says 0 m/s. This is your relative velocity.

5) Burn towards the target (pink bullseye) a bit, time warp to the next intercept, burn retrograde to reset relative velocity to 0.

6) Repeat step 5 until you're on top of them. If you're already close, might want to go easy on the throttle.

If fuel use is a concern, you can limit the prograde burn in step 3, though it will take more orbits to get close. This reduces the initial dV and the amount of relative velocity you need to kill. Likewise, you can skimp on step 5 a bit - will take less fuel, but more orbits to get there.

If your target is in a very high orbit, and you are in a low orbit, simply use a maneuver node to directly intercept them where target position and intersect point match. At that point, burn retrograde at the target like the dickens to match the orbit.

Docking itself is a bit of a pain without RCS or Vernor thrusters. If those are unavailable or unappealing, consider using spider engines at low throttles with the main engine turned off. Hitting your target with heavy rocket blasts is counter-productive.