Ok, when I posted this challenge, I set the fuel amount & time limit based on some rough estimates. Today, I just flew this challenge and would like to share some information here.
First of all, assuming you have the right plan, the fuel spent in MCCs will differ from person to person depending on what MFD they use & when they perform the MCCs.
So, to minimize the fuel used in MCCs, I use the following technique.
I'll use an example of a ship going from Earth to jupiter, then slings jupiter to get to Uranus.
When to perform the MCCs? It's generally a good idea to perform a MCC when the
time after orbit ejection/time after Previous MCC = Half the time left to reach your target. This means, let's say it takes 80M(million) seconds to get to jupiter, this means I would perform a MCC when
time left to reach jupiter = 40M, 20M, 10M, 5M & so on until the I get close enough to jupiter for the PeA value to stop fluctuating. I guess most people already know this from Blixel's videos.
Now, what tools to use to perform the MCC? I first set up the plan to reach jupiter along with the sling to Uranus in TransX and transfer the ejection burn values to IMFD using the deltaV program. This allows me to use the highly accurate Map program of IMFD. Then, I set up the plan in IMFD to get close enough to jupiter & execute the burn.
When the
time left to reach jupiter has halved, I correct the outward angle & Inclination angle in transX to reduce my Cl. App. value
with respect to Uranus. Once that's done, I perform a MCC using transX, to get the
R Inc value to 0 & Pe Ratio value to 1.
Then, I open the IMFD map program & use the following settings.
Now, I target Uranus in IMFD map program & even though I'm only
halfway to Jupiter, I'm able to see my encounter at Uranus. Due to our MCC executed using transX just earlier, the PeA value at Uranus won't be way off. Then, I use the deltaV program of IMFD to perform corrections as per the IMFD map program, to correct my jupiter sling to uranus.
This way, we can use the IMFD map program to execute slingshots planned using TransX
more accurately.
Now, back to this challenge, after
3 1/2 hours and patiently planning & executing more than
20 MCCs throughout my journey, I was able to get to Varuna
without using the scenario editor to skip to the future. I even auto centered manually to save some RCS fuel.
I still had a total of
160 dv left after the fly by. Time of flight was
19.85 years which is just under 20 years, even though my plan in TransX said it would take 19.55 years. I guess it's not surprising that transX was off by some 0.2 - 0.3 years, especially for long flights such as this one. The way we perform our MCCs affects our time to reach our target in that 0.2 - 0.3 year range.
I think my TOF limit is just too tight, you'll need to know the optimum launch date
as well as the optimum fuel to be burnt to achieve something like this. So I'm revising my TOF limit to
22 years.
Also, 10 km altitude at Varuna seems too low, I went inside Varuna's mesh & came out of it from the other side. So I'm also revising the fly by altitude to
100 km.
No change in the fuel limit because I'm allowing the use of scenario editor to skip to the future.
Original post updated.