How long does it take to go 20k lys? My Palin run nearly broke me at 110 jumps so lord knows how you commanders stay out in the black for so long...
There are many factors. Let's say you had a 50ly jump range - that would be around 400 jumps. Each jump should take just under a minute. So, ~400 minutes is around 6.5hrs.
Obviously you can get a better jump range with the right ship and some engineering. You can also use neutron boosts and/or FSD injection to push things even further. If you tick the "Use jet cone boost" option under route plotting then the route plotter will route you past white dwarf and neutron stars that happen to lie roughly along your route in order to take advantage of these. Alternatively you can use the excellent "Spansh" site to find routes that will go out of their way to find neutron stars for you and this can give you enormous increases in travel speed. Be warned tho - using neutron boosting damges the FSD over time so you'll need to stop and repair your FSD with an AFMU occasionally (basically whenever it gets down to 80% integrity if you want to avoid FSD malfunctions). If you reall push things and use every advantage you have you can get from Sol to Sagittarius A* (nearly 26,000ly) in under 2hrs!
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