How to Rendezvous to my space station!?

[GamerMitch]

I've sent a space station (all one piece) into orbit, and I can't seem to Rendezvous with it.I can get an encounter of about 3 km.When it comes close I burn toward it, but it just speeds on past.How can I successfully rendezvous with my station?I didn't put it up there for nothing...

[s1l3nt_c0y0t3]

I've sent a space station (all one piece) into orbit, and I can't seem to Rendezvous with it.I can get an encounter of about 3 km.When it comes close I burn toward it, but it just speeds on past.How can I successfully rendezvous with my station?I didn't put it up there for nothing...

Velocity matters. You can't just thrust up to be in the same place as your station. Anything in orbit will have a lateral velocity of over 2km/s. You need to get your ship moving at the same speed or your station will just wiz right by you.

I put my stations @~75km altitude. I do this because I use them as fuel stations before taking my ships further out. A lot of other people put their stations @~100km. The altitude matters because the higher you go, the faster you have to be moving. I don't know what the orbit is like for your station, so I'll give you directions for both altitudes.

First of all, you can't launch when your station is directly overhead. You have to give yourself time to get up to speed. You also have to factor in that you'll be accelerating pretty much the whole time. This means your relative velocity will be dropping. This will make the station seem to slow down over time; it will close most of the distance with you early on. For a 75km rendezvous, you're going to want to wait until the station is ~45-50 degrees behind you, depending on how fast your craft accelerates. (Heavy loads need more of a lead, lighter loads need less.) For 100km, you'll want a 75-90 degree lead. Launch like you normally would to attain a circular orbit. You should be a bit ahead of your target. This is a good thing. In low Kerbin orbit, it's easier to drop back relative to another craft than it is to catch up to one. Select your station as a target. Wait for either the ascending or descending nodes (green triangles) in the map screen. For ascending nodes, place your navball reticule on the horizon between the orange and teal hemispheres at 180 degrees. Wait until you're about ten seconds away from the node and thrust until your relative inclination drops to 0.0. For descending nodes, point at the horizon at 0 degrees, which will be marked with an orange line, and thrust until your relative inclination drops to 0.0. Watch out, the lower the inclination, the faster it will drop. The node should have moved ahead of you after you thrust. Wait until you approach the node again (it doesn't matter which one for this part). Then thrust prograde (the upside-down T in your navball) until the close approach icon drops as low as you can get it. When you approach the the station, you want to switch your navball from "ORBIT" to "TARGET". Then thrust retrograde until your relative speed drops to 0, or at least below 5. The point at the target vector (magenta circle) and thrust to head towards the station. I wouldn't let your relative speed get much above 50m/s. Flip around to the retrograde marker again. When you get close enough to the station to start using RCS, thrust retrograde to bring your relative velocity down to below 5, or less if you don't have many RCS thrusters. Then just dock normally.

Enjoy.

[Dave Kerbin]

When you get close to it you first need to zero out your velocity. Because there is no friction in space the burn you make in the direction of the station is only adding to your velocity, not overriding it.

So when you get to around 4km or less do this:

1. Make sure you have the station as your target. At 4km you should see the orbit speed above the navball be replaced with a relative velocity.

2. Point your ship at the retrograde marker and burn until the relative velocity is about 0m/s (as soon as you stop burning it will start building up speed because your orbit is different so don't worry about getting from 0.1m/s to 0.0m/s)

3. Point your ship at the target prograde marker and burn until you have some velocity. At a range of 4km I would suggest getting up to about 10m/s.

4. Check the map again. You'll see a new rendezvous plotted a few minutes away, probably around 0.5km depending on how accurate your burn in step 3 was.

5. When you get to the next rendezvous do the steps again, only with a smaller burn in step 3. When you get under 200m you should start using RCS for your burns.

As you get used to this you'll start to understand how your velocity and direction are affected by burns. You'll make fewer burns and be able to take shortcuts like accurately changing your velocity vector without zero-ing out first. If you master it you'll be able to dock without RCS at all.

[HeadHunter67]

As others have pointed out, simply burning straight toward it is guaranteed to miss, because you're not only increasing the difference in your relative velocity, you're also changing the altitude (and possibly inclination) of your orbit.

I'd recommend watching PebbleGarden's Phoenix Project videos on YouTube, and trying out Blizzy's Rendezvous Tutorial.

[lincourtl]

I'd recommend watching PebbleGarden's Phoenix Project videos on YouTube, and trying out Blizzy's Rendezvous Tutorial.

Yes! This! Both PebbleGarden's videos and Blizzy's Rendezvous and Docking tutorial mods are excellent.

[blizzy78]

Interactive in-game rendezvous tutorial