Challenge Low energy Earth-Moon transfer

[MontBlanc2012]

This challenge is a similar transfer to an earlier "Low energy Moon-Earth transfer" challenge.

The scenario starts with DeltaGlider in a standard 300 x 300 km Low Earth Orbit. It has 3475 m/s of main and RCS fuel. The objective is straightforward: transfer the DeltaGlider to a circular lunar orbit with an orbital altitude of 10,000 km or less.

As with the Moon-Earth challenge, this problem should be impossible using a standard Apollo-style Earth-Moon transfer so, again, some 'outside of the box' thinking is required.

Hint 1: TransX is not likely to be of much use.

Hint 2: You may want to try using Lagrange MFD in conjunction with IMFD. For some reason, Lagrange MFD's integration engine seems a little more stable than IMFD's Map Program for this particular problem - and using it seems to reduce MCC requirements by a large margin.

Here, in text form, is the challenge scenario:

BEGIN_DESC
This scenario starts with DeltaGlider in a standard 300 x 300 km Low Earth Orbit.  It has 3475 m/s of main and RCS fuel.  The objective is straightforward: transfer the DeltaGlider to a circular lunar orbit with an orbital altitude of 10,000 km or less.
END_DESC

BEGIN_ENVIRONMENT
  System Sol
  Date MJD 51985.7065975741
  Help CurrentState_img
END_ENVIRONMENT

BEGIN_FOCUS
  Ship GL-02
END_FOCUS

BEGIN_CAMERA
  TARGET GL-02
  MODE Cockpit
  FOV 50.00
END_CAMERA

BEGIN_SHIPS
GL-02:DeltaGlider
  STATUS Orbiting Earth
  RPOS -6406292.098 588742.155 -1764949.382
  RVEL 2050.0653 -35.4100 -7452.9995
  AROT 147.185 -38.255 25.794
  VROT 0.0246 -0.2133 -0.0138
  AFCMODE 7
  PRPLEVEL 0:0.076749 1:0.013845
  NAVFREQ 586 466 0 0
  XPDR 0
  HOVERHOLD 0 1 0.0000e+000 0.0000e+000
  AAP 0:0 0:0 0:0
  SKIN BLUE
END

And .zip file is attached for those that want to install the .scn file without resorting to cut & paste.

As with the low energy Moon-Earth transfer, I may provide a sample solution in comments below

 

[MontBlanc2012]

And here is a link to a sample solution to this challenge:

Best viewed with subtitles on.

 

[BrianJ]

Another fun challenge for Lagrange point fans
This Lunar-flyby-to-Earth/Sun-L1 solution fell out pretty easily. Did you set it up on purpose?

3113m/s ejection burn after 7/8 orbit...


Just before Lunar flyby, could go to L1 halo orbit from here......


1st course correction......


2nd course correction....


Adjusting the encounter.......


Setting up the orbit insertion burn....


In polar orbit, looking down on North Pole......


Good fun! Cheers,
BrianJ

 

[MontBlanc2012]

This Lunar-flyby-to-Earth/Sun-L1 solution fell out pretty easily. Did you set it up on purpose?

No, not especially. The solution I found was actually two days in the future.

What this shows, I think is that so long as one isn't aiming for the absolute lowest possible dV requirement, the solution to this problem is quite date tolerant offering a fairly large transfer window.

---------- Post added at 12:06 PM ---------- Previous post was at 11:59 AM ----------

Addendum: having looked at BrianJ's screenshots, I note that he managed to save some fuel by incorporating a lunar flyby and so getting a bit of a gravity assist.