Grand Tour

[MAFman]

When is there a window for a grand tour Voyager 2 style, in the Outer Planets Mod? Sorry if this is too off topic.

[Zhetaan]

4 hours ago, MAFman said:

When is there a window for a grand tour Voyager 2 style, in the Outer Planets Mod? Sorry if this is too off topic.

I found forty-four flyby trajectories of varying quality.  In the interest of giving you workable results, I neglected to refine the search any more than I did, but I will caution you that these are all untested and should be taken as theoretical until proven otherwise.  Also note that the plot is, for lack of a more accurate term, weird, in the sense that there is no discernible periodicity.  Given that real-life alignments of the outer planets occur approximately 175 years, I suspect that this is largely due to too short a search window.

Also please note that, given the travel times, some (or most) of these probably work out to have phasing orbits that take a turn around the sun before encountering the next planet in the tour.  This is not a problem when considered from the standpoint of a valid flyby, but given that you want to reenact a Voyager 2-esque mission, I elect to share only the five trajectories that have the shortest travel time.

Path	dV	Start Day	Jool Encounter	Sarnus Encounter	Urlum Encounter	Neidon Encounter	Total Time
1	3195	160	630	9843	14612	32220	32060
2	3611	232	664	9940	14830	33660	33428
3	3083	220	664	9942	14875	34140	33920
4	2737	208	664	9943	14912	34530	34322
5	2576	196	664	9945	14957	35055	34859

Note that these are all fairly similar; using the shortest travel time ultimately leads to that because I'm essentially choosing from only the pointed left side of the porkchop plot.  Note however the difference of 2799 days between the first and last trajectories on this list:  that is over six and one-half Kerbin years.  It's not much, in light of the orbital periods of the planets, so these properly could be termed subsets of the same trajectory (and I did eliminate two of my results for being too similar to ones on the list).

• Path 1:  Start Planet: Kerbin
  Orbit Departure Time:
     3434400 seconds UT
     160 days UT
  Start Orbit Inclination: 7.5 degrees
  Start Boost from that incl.: 3195 m/s
   
• Path 2:  Start Planet: Kerbin
  Orbit Departure Time:
     4989600 seconds UT
     232 days UT
  Start Orbit Inclination: 2.8 degrees
  Start Boost from that incl.: 3611 m/s
   
• Path 3:  Start Planet: Kerbin
  Orbit Departure Time:
     4730400 seconds UT
     220 days UT
  Start Orbit Inclination: 3.5 degrees
  Start Boost from that incl.: 3083 m/s
   
• Path 4:  Start Planet: Kerbin
  Orbit Departure Time:
     4471200 seconds UT
     208 days UT
  Start Orbit Inclination: 4.3 degrees
  Start Boost from that incl.: 2737 m/s
   
• Path 5:  Start Planet: Kerbin
  Orbit Departure Time:
     4212000 seconds UT
     196 days UT
  Start Orbit Inclination: 5.2 degrees
  Start Boost from that incl.: 2576 m/s

You are absolutely welcome to find and make refinements.  There are likely many to be had; however, a set of trajectories that will actually get you there will at least get you closer to a true Voyager-like solution.

[MAFman]

Thanks!!