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The following represents one way to accomplish the task. There may be many solutions. The procedure has been broken down into 21 separate steps. Each step has a starting scenario. To obtain all the scenarios for these steps download and extract all the .scn files in this zip file. Extract them into your Orbiter folder, it will automatically place them into a "Scenarios/Jupiter_Landing" folder.

STEPS:

1. Plan a flight with "I" to launch Io and eject to Europa and insert a fairly equatorial orbit around Europa. Launch "E" and dock with "I". (use scenario 01.scn)

2. Using "I", push the combination of "E" and "I" out toward Ganymede. Arrive with retrograde (heading west). (use scenario 02.scn)

3. Nearing Ganymede when a few Ganymede diameters away, plan a prograde burn at some point during the encounter, that allows a result with a low Pe at Jupiter. Shoot for about 70.6 M as radius. The object is to minimize fuel use with "I". To go to a low Pe at Jupiter directly from Europa is much more fuel and would require that "I" would eventually need help getting back to Io. This method allows enough fuel for "I" to get back unaided. Very important since both "G" and "C" will be needed to get "E" back home. (use scenario 03.scn)

4. After the flyby with manoevre at Ganymede do a cleanup burn with E to be sure to be somewhere at 70.6 M radius. Then when half way to Jupiter, undock and with "E" do a burn to drop the Pe of "E" to about 550 Km agl. Be sure that I has a Pe of about 750 Km agl. (use scenario 04.scn)

5. On approach to Jupiter fly both craft simultaneously into the atmosphere. Have "I" upright so that it just richochets off the atmosphere while "E" is manoevered to level off at about 550 to 600 Km agl and stable in altitude. You will need to be inverted and pulling a couple to 3 g's to maintain this height. Soon "I" will be leaving the atmosphere and you can concentrate on the landing of "E". Land on the equator. (use scenario 05.scn)

6. After "I" has left the atmosphere and 'E" has landed on Jupiter plan the next entry of "I" to aerobrake. You'll need to aerobrake to get the orbit of "I" to have the Ap down to match the orbit of Io and also aligned with Io. You will need to roll inverted on reentry to dive deeper to be able to aerobrake for a while. If you can't hold it on the first entry and are leaving the atmosphere, after passing the Pe roll upright to climb as much as possible as this will drop the Pe for a better chance to aerobrake on the subsequent orbit. After leaving the atmosphere with the best aerobraking done, at the Ap burn prograde to lift the Pe up out of the atmosphere. 1.5 M agl can work. (use scenario 06.scn)

7. The aerobraking is complete and you have an orbit aligned with Io and the Pe is out of the atmosphere. Plan the necessary burn to intercept Io. Minimize the burn to save fuel. Wait several orbits if necessary. Use the "Orbits to Icept" function in TransX. (use scenario 07.scn)

8. "I" is arriving back at Io. Burn to insert the orbit and then land on Io. Be careful, you are very limited on fuel. Hint: use as much RCS LIN to insert the orbit and reduce the orbit size. (use scenario 08.scn)

9. Launch "E" from Jupiter and use only 3/4 throttle in the lower atmosphere with thrust middle trim and thrust vectoring to control pitch to climb at 45 to 50 degrees above the horizon. Get into low orbit at 1.6M to be clear of the atmosphere then push the Ap up as much as possible yet leaving enough for a landing back at Europa. The plan ultimately will be to use "G" and "C" to get "E" into orbit around Europa, so only enough fuel to go from low Europa orbit to a landing will be needed. (use scenario 09.scn)

10. Launch "C" from Callisto and eject to drop to a low Pe at Jupiter for aerobraking. You decide the best launch window to do this. Get the Pe to be down to about 600 Km agl. (use scenatio 10.scn)

11. Aerobrake in Jupiter atmosphere to match the orbit of "C" to match as close as possible to that of "E". (use scenario 11.scn)

12. You have just left the Jupiter atmosphere. Now rendezvous "C" with "E". Be careful not to aerobrake any more. (use scenario 12.scn)

13. Use "C" to push "E" up as much as possible leaving "E" now in a higher Ap orbit probably above the orbit of Io. You must leave enough fuel on "C" to transfer it back to Callisto for orbital insertion and landing on its own. Undock. "E" and "C" are now vulnerable from being disturbed by Io and dropping their Pe's into Jupiter. Be careful. (use scenario 13.scn)

14. Plan an expansion of the orbit of "C" to return it to a landing on Callisto. While waiting for the window to arrive do steps 15 thru 17. But don't miss this window for the transfer to Callisto while being distracted by the remaining steps. (use scenario 14.scn)

15. Find the launch window and execute the launch of "G" from Ganymede with eject to a low Pe at Jupiter. The object is to match the orbit of "C" with "E" and then dock with it. You can use aerobraking if you think you need to save fuel or just burn the Ap down using fuel. The engine method is more precise but if done right the aerobrake method does save a bit of fuel. (use scenario 15.scn)

16. Using "G", thrust "E" up to intercept Europa and to insert it into low Europa orbit. (use scenario 16.scn)

17. Undock "G" from "E" then land "E" on Europa. (use scenario 17.scn)

18. The time has come plan and execute the manoevre to thrust "C" from its Jupiter orbit back to Callisto. At this point, "I" is on Io, "E" is on Europa, and "G" is in low Europa orbit waiting for the chance to return to Ganymede. (use scenario 18.scn)

19. Land "C" on Callisto. (use scenario 19.scn)

20. Plan and execute the trans Ganymede burn to send "G" back to Ganymede. Then do the orbit insertion burn. (use scenario 20.scn)

21. Land "G" on Ganymede. (use scenario 21.scn)

22. All DG's now back on their home moons. Total fuel remaining is 1,460 Kg of the initial 54,000 Kg. (use scenario 22.scn)