How on earth do I reach this orbit for rendezvous?

[Interstellar Yeet]

So I have this rescue mission and I've seen tutorials on rendezvous but I have no clue how to do it other than in low kerbin orbit. https://imgur.com/a/ilYESDb this right here is where I'm at, and you can see the pod near the Muns orbit. 

[HebaruSan]

1. Launch your rescue craft into low orbit in the plane of the rescuee (looks roughly equatorial, but hard to tell from that angle)
2. Place a maneuver anywhere on the orbit
3. Increase the maneuver's prograde  vector until your post-maneuver Ap touches the target orbit (should be 800-900 m/s given how close it is to the Mun)
4. Drag the center of the maneuver forwards around your orbit till you get close approach markers; try to bring them close together
   (if you drag backwards there's a risk you'll drag the maneuver into the past, which can lock it up)
5. Fine tune the maneuver to get the closest rendezvous you can (0.0 km is generally possible but can be tricky)
6. Execute the maneuver
7. Click your orbit several minutes out from the close approach and "Warp To Here"
8. Switch the nav ball to Target mode
9. Set your SAS to retrograde  mode (if you have it, otherwise point that way yourself)
10. As you get closer to the rendezvous point, say at about 1-2 minutes till close approach, burn a bit here and there and watch what happens to your close approach distance and speed. Both should be small and decreasing, but you sometimes have to pitch and yaw a bit to make that happen.
11. Try to keep your time till encounter above 45 seconds by burning near-retrograde, until your approach speed is negligible (say 10-20 m/s)
12. Now you should be able to comfortably drift into range and zero out relative velocity at your leisure

Edited November 4, 2018 by HebaruSan

[TanDeeJay]

15 hours ago, HebaruSan said:

• burn a bit here and there and watch what happens to your close approach distance and speed. Both should be small and decreasing, but you sometimes have to pitch and yaw a bit to make that happen.
• Try to keep your time till encounter above 45 seconds by burning near-retrograde, until your approach speed is negligible (say 10-20 m/s)

It is possible to meet the other ship without having to guess the "pitch and yaw a bit" by always burning towards your target to speed up and get closer, or to burn retrograde to slow down.  I'd do all the other bits mentioned here, but once your distance gets less than a few  K, burn retrograde until the speed difference is 0.0m/s (as I get better at doing that maneuver I've been reducing that distance to less than 2k)  Note:  the greater the initial speed difference as you approach the rendezvous point the further out you need to start burning to slow down.  HebaruSan's suggestion of burning retrograde at 45 seconds from the encounter sounds like a brilliant idea that I'm going to have to try.  I've always previously just looked at the distance.  45 seconds out would mean the burn would always start at an appropriate distance from the encounter, rather than the way I currently guess as to what is an appropriate distance.

Once I've reduced the speed difference to 0, then I set the SAS to target mode and burn prograde (or manually point navball at target marker if SAS can't target another ship) (now you need to be careful here... if you killed your velocity difference at 5k, then you can speed up more than if you killed your velocity difference at less than 1k) if your closer to 5k distance, then use your main rocket to increase your speed to 20 - 25 m/s   if your a lot closer, it might be safer to use your RCS thrusters to increase your speed ('h' key) to a smaller value

as you get closer you'll need to decrease your speed  to ensure you don't overshoot.  But... when decreasing your speed, point your SAS at the retrograde marker if you need to use your main rocket to slow down, or point your SAS at the prograde marker to use your RCS ('n' key) to slow down.  (never slow down to less than 0m/s as that will start pushing you away)

if the target marker and prograde/retrograde markers are not aligned on the navball, when you slow down, you'll want to slow to 0m/s again, and then point at the target marker again.

Well, thats how I do it anyway... there may be more efficient methods, but this way your not trying to guess which way you need to pitch or yaw.

 

Rendezvous in high kerbin orbit is similar to in low kerbin orbit, its just that if your starting from a low kerbin orbit, you just have  a greater difference in speed between your 2 ships that you need to neutralize.

 

One thing to watch is that when your setting your rendezvous maneuver, just watch that your maneuver doesn't put you into the SOI of Mun.  that will throw off your rendezvous orbit.  do an orbit or 2 more of kerbin if you need to, as that will change the rendezvous point. Actually, thinking about this, you probably don't need to worry about this, as your stranded ship is already in the same orbit as Mun, but not in the same place on the orbit, so forget I said that 

NOTE: HebaruSan's point 8 is extremely important!  You want to perform your burns with navball set on target... Too many times I've forgotten this step only to find I've just changed my orbit to intercept the ground, and then not had enough fuel left to correct  

 

Cheers,

John

 

Edited November 4, 2018 by TanDeeJay
Corrected comment about meeting the SOI of Mun

[HebaruSan]

27 minutes ago, TanDeeJay said:

It is possible to meet the other ship without having to guess the "pitch and yaw a bit" by always burning towards your target to speed up and get closer, or to burn retrograde to slow down.  I'd do all the other bits mentioned here, but once your distance gets less than a few  K, burn retrograde until the speed difference is 0.0m/s (as I get better at doing that maneuver I've been reducing that distance to less than 1k and even managed less than 100m once)

This can work, but it's unnecessary and a little wasteful as you're eliminating velocity that you already have and then adding some back again, essentially cancelling out part of the previous burn. As long as you control the time and distance of the rendezvous properly, you can make it as close and slow as you like without stopping or reversing direction.

The "pitch and yaw a bit" doesn't have to involve guessing, but it's somewhat difficult to give a complete description while still keeping it clear enough for a new player to follow (and it's always good to experiment anyway to understand how it works). The trick is to orient your ship so your mostly-retrograde thrust "pushes" your retrograde marker  toward the anti-target direction , which results in a closer encounter while simultaneously slowing your approach speed. Keep doing that whenever your time till rendezvous is at or below 45 seconds, and eventually you'll be so slow and so close that you're effectively already rendezvoused.

[Kerbinchaser]

17 hours ago, HebaruSan said:

(snip)

 

Yeah, well... What he said.