Ship Delta V calculator in 1.2x ?

[AeroGav]

Just a quick one for you guys,  is there a mod to calculate a vessel's current delta V in flight?  Previously I uses Kerbal Engineer,  I did install it under 1.2.1 but it seems it doesn't take account of the new way fuel is handled in 1.2 - my spaceplane has nukes but they are not part of the same stack as my liquid fuel tanks, as there are no fuel ducts, kerbal engineer doesn't seem to realise that fuel can get to those nukes, so assigns me a very low delta V value.

I'm in a career game and just flew this Whiplash/Dart/Nerv contraption to orbit.   I was hoping to go to Gilly as it's Bill's first trip to space.   I've developed an aversion to docking maneuvers and was hoping i wouldn't need to refuel the thing.

We got 2709 LF remaining and are currently massing at 36.86T.

 

[Plusck]

I made a spreadsheet specifically for this reason. KER was constantly switching between airbreathing and closed cycle modes, and seemed to be getting it all wrong. So if you have a recent version of Excel it might help you too. It should be pretty self-explanatory - put known values in the first (yellow) set of columns and the columns on the right try to fill in the blanks. I can't remember whether the Spark has the correct Isp or the old value though...

P.S. The spreadsheet tells me you have 3594 m/s...

edit: the Spark was effectively using the old values. Updated it to fit what's given in the wiki.
edit 2: there were a few more changes in 1.2 which I hadn't spotted. Updated.
 

Edited November 12, 2016 by Plusck

[Foxster]

Both KER and MJ aren't updated to take into account the new fuel flow mechanic. You can overcome this by adding fuel ducts like you would have pre-1.2. Not the best thing but it does get the numbers right then. 

[ForScience6686]

Just run the math,  it's quite easy,  and once done enough  you can get answers in seconds.

DV=(9.81*isp)*ln(wet mass/dry mass)

Just take your fuel units and multiply by .005.   subtract from your current mass to get your dry mass then plug it into a calculator.

[crackerbal]

actually in your design it would be impossible but on a very basic design of ssto with 2 nervs connected to the central bicoupler once i drain all the fuel remain on the radial attach fuel tanks (rapiers) to the center, the KER reading become exact

anyways with the sstos i'm usually re-lay on what am i learned from previous designs the deltaV can change drasticly and u can to change it aswell depending on using more or less oxidiser for some maneuvers like for exemple take off from duna or using Venom rcs ( witch are inculding the consuption of bipropleant )

there is no better answer then @ForScience6686 gaves u... just apply the formula