Having trouble getting home.

[HedgeKnight]

hey folks,

im on the mun in the SW crator. I have 904dV @3.41 twr
https://www.dropbox.com/s/50lb2u5pxtfpcp1/Kerbal Space Program 2023-02-02 8_31_41 PM.jxr?dl=0

I cant seem to figure the launch window or parking orbit window to get home Ive tried so many headings at low angles; what am I  doing wrong?


please help.

Cheers

j
 

[Vanamonde]

Need to log in or something to see your pic? Can you host it someplace like Imgur.com? Accounts are free. 

Anyway, Kerbin is a big target. If you can reach orbit at all, just burn while you're on the prograde side of Mun.

That should drop you off something like this. 

[HedgeKnight]

https://www.dropbox.com/s/x3012i3p3eosgql/home help..PNG?dl=0

That should work...

The prograde side ... of the mun... ? C.C. (east) on the mun matches how the mun also rotates C.C around kerbin yes? so the prograde side is basically to try to fly ahead of the mun?
the problem is that when ever I launch I end up on an insanley high inclination.. and my transfer is way off the equatorial plane...

my ship is Excusion I

and thx for the help.

j

Edited February 3, 2023 by HedgeKnight
add

[Leganeski]

12 minutes ago, HedgeKnight said:

the problem is that when ever I launch I end up on an insanley high inclination.. and my transfer is way off the equatorial plane...

This is because you landed so far away from the equator. Thankfully, when coming back from Mun, there's a relatively simple solution to the problem of inclination.

• After reaching low Mun orbit, create a 290 m/s prograde maneuver, and move it around until the planned trajectory exits Mun's sphere of influence horizontally. (The maneuver should be positioned about 45 degrees after your orbit crosses the equator.) This gets rid of the inclination by using Mun's gravity to rotate your velocity towards the direction you want.
• Click the "next orbit" button repeatedly until the planned trajectory reaches Kerbin. (This could take up to 60 orbits, depending on where Mun is.)
• Execute the maneuver.

[Vanamonde]

Is there some reason you need to stay on the equatorial plane? It should be just about as easy to return to Kerbin off of it  as on it. 

[king of nowhere]

9 hours ago, HedgeKnight said:

https://www.dropbox.com/s/x3012i3p3eosgql/home help..PNG?dl=0

That should work...

The prograde side ... of the mun... ? C.C. (east) on the mun matches how the mun also rotates C.C around kerbin yes? so the prograde side is basically to try to fly ahead of the mun?
the problem is that when ever I launch I end up on an insanley high inclination.. and my transfer is way off the equatorial plane...

Not ideal, inclination complicates things in ways that are difficult to explain...

still, ending up in an inclined orbit around kerbin is not a big deal. do that, reach apoapsis, and burn retrograde to lower periapsis and get captured by the atmosphere.

Now that I see if, you only have 900 m/s. that's very short. Returning to kerbin with so little fuel from an inclined orbit would not be trivial for me either. You have to orbit mun in an inclined orbit, then manage to get ejected equatorially. There is a point in your orbit, if you make your burn there, you will start leaving mun and you will exit the SoI just when your speed is horizontal. You can find it by trial and error.

Then, once you find that, you also need to eject when mun is in the right point in its orbit that you will exit retrograde. Again, you do it by trial and error by moving your maneuver to future orbits.

Basically 1) orbit mun; this should consume 600 m/s, leaving you with 300 m/s.

2) make a 300 m/s maneuver at a random point in orbit. Check how that orbit would do once in kerbin's SoI.

3) move it around until you get a low kerbin inclination

4) now start clicking on "next orbit" until your maneuver also results in a low periapsis - low enough for aerocapture.

this is the clearest I can explain. I hope it is enough

[HedgeKnight]

14 hours ago, Leganeski said:

This is because you landed so far away from the equator. Thankfully, when coming back from Mun, there's a relatively simple solution to the problem of inclination.

• After reaching low Mun orbit, create a 290 m/s prograde maneuver, and move it around until the planned trajectory exits Mun's sphere of influence horizontally. (The maneuver should be positioned about 45 degrees after your orbit crosses the equator.) This gets rid of the inclination by using Mun's gravity to rotate your velocity towards the direction you want.
• Click the "next orbit" button repeatedly until the planned trajectory reaches Kerbin. (This could take up to 60 orbits, depending on where Mun is.)
• Execute the maneuver.

Oh brilliant.

Ya, Mun Bugbase was a 'go fix the rover' mission with 'land a base on the mun' mission.

Stranding them there; they did their service, time for some R&R, the engineer and pilot needed to come home.

Thanks King, and Legansinki this did!! Great description of the instructions too.

Their home.

 

Edited February 3, 2023 by HedgeKnight