Question about the Porkchop Plot and d/v

[JoeSchmuckatelli]

Ran a TWP for Duna.  It gave me 1687 of d/v.  I figured that was the d/v I'd need to get the encounter and set up a node looking for it.  Apparently I was wrong about this.  After quite a bit of fiddling, I found an intercept with good Duna Periapsis - but at about 1100 or so (dont remember the details).  It was kind of an ugly approach - but the Mun was in the way for what I presumed was the correct line; so I took what I could get.  Coming in hot, it's going to take 1500 or so d/v to orbit.

Thankfully, my overbuilt ship can handle this; but it begs the question...

Is the TWP prediction of 1687 for the escape AND the capture at Duna?  (because if so... I've just wasted a LOT of fuel)

Thanks

[antipro]

45 minutes ago, JoeSchmuckatelli said:

Is the TWP prediction of 1687 for the escape AND the capture at Duna?

you mean "Is the TWP prediction of 1687 correct for the escape AND the capture at Duna?"

I don't know your start and destination orbit but I've tried from LKO at 120km to Duna orbit at 1000km and
MJ gave me 1066+500=1.566.
 

Edited December 15, 2020 by antipro

[JoeSchmuckatelli]

Well - see, that's the problem - clearly I don't know what a pork chop plot is showing.  I thought it was purely an encounter thing - not something that combined encounter with capture. 

[Streetwind]

Transfer Window Planner has an option that says "flyby only", which you can select if you do not want to perform an insertion burn. This is useful not just for flybys, but also for atmospheric worlds where you can aerocapture.

If you selected this, then the dV cost is for the transfer burn only (plus midcourse correction, if you got one). If you did not select this, then the dV cost is for both transfer and propulsive capture.

You say you got a transfer node with about 1100 m/s; that sounds perfectly fine for a good in-window Duna transfer. That leads me to believe that the rest of the total sum accounted for a propulsive capture.