DeltaV

[GoSlash27]

1 hour ago, magnemoe said:

You also have the advanced option to drop your Pe down to 100 at the place and time of the burn, this have you moving at over 3 km/s at the start of burn, this has two benefits, first you save 7-900 m/s, second you get more out of Oberth and higher starting speed, downside is that this take time to set up, however its very nice then launching heavy stuff towards Moho or Eeloo. 
 

magnemoe,

 Surprisingly, most destinations actually wind up costing more DV if you drop all the way back down before transfer. That's the weird balance between Oberth and the gravity well.

Every destination has an ideal periapsis to depart from, and this ideal altitude is somewhere higher than LKO.

I ginned up a handy list. Hang on, I'll see if I can find it...

(rummaging noises...)

Ah, yes. Here we are (adjusts glasses, clears throat)

Moho: Periapsis 680 km
Eve: Depart directly from Mun
Duna: Depart directly from Mun
Dres: Periapsis 1 Mm
Jool: Periapsis 360 km
Eeloo: Periapsis 210 km

Best,
-Slashy

 

[Red Iron Crown]

7 minutes ago, GoSlash27 said:

Ah, yes. Here we are (adjusts glasses, clears throat)

Moho: Periapsis 680 km
Eve: Depart directly from Mun
Duna: Depart directly from Mun
Dres: Periapsis 1 Mm
Jool: Periapsis 360 km
Eeloo: Periapsis 210 km

Interesting. Have you run the numbers from Minmus?

[GoSlash27]

RIC,

I haven't, since none of the gate altitudes exceed the Mun and other assorted difficulties involved with departing from Minmus.

I can run them if you like and get back to you on it.

Best,
-Slashy

 

[magnemoe]

1 hour ago, Red Iron Crown said:

I took that to mean 7-900 m/s over starting in LKO (i.e. your speed at Pe will be about that much more than LKO speed); those savings are not from Oberth but from the initial orbit having greater energy.

Yes, first keep most of the energy used to get to Minmus, some losses as you has to do various burn to get into position, I went to kerbin orbit around Minmus then adjustment burn so my low flyby was timed then the burn to drop Pe, however the increased speed get you more out of the Oberth Effect, you start faster, the burn is shorter and you don't have to fight gravity for so long as you do with an burn from LKO, as an extra bonus the burn was more accurate than long burns from LKO tend to be so the correction burn was small.