You want to burn away your horizontal as you fall so that by the time you get to the bottom your going more or less straight. Whilst it's more efficient to burn at an angle to lose the velocity in an arc, you can just suicide your horizontal and fall if you have the delta-v to spare.
The problem I have is with any kind of rendezvous. Cannot get two space craft to deliberately meet...Makes Apollo-style missions tricky 
Oh, man, I finally figgured this out. I was having the HARDEST time with it, but could never get it right. With the new "rescue the kerbal" missions, i finally knuckled down and got it sorted out.
I'm going to guess that your problem is similar to mine. Something like this:
- You can match orbital plane by adjusting the purple triangles on the maneuver nodes - normal and anti-normal. no problem
- you can match orbit shape by burning at periapsis and apoapsis. no problem
- you can get roughly close to another orbital object by making your orbit larger (to slow down) or tighter (to speed up). no big problem.
but the PROBLEM comes in closing the last few km or few tens of km. and the solution to this is to use the nav-ball.
When the nav-ball is set to your target (pick a target, and click on the nav-ball until it gives you the target's velocity) you can:
1 - burn at the retrograde indicator to make your velocity relative to the target zero. This will effectively match orbits exactly with the target.
2 - burn at the "towards target" indicator to close distance with the target
3 - go to step 1 and zero out velocity again. repeat as you close. maybe use RCS instead of engines.
I struggled with this for so long, and finally figuring out how the "target" navball worked was a life saver.
Author
Topic: Kerbal Space Program: Now Hiring Optimistic Astronauts for Dangerous Munission (Read 1501425 times)