Can I land on Ike and return?

[Gapone]

It's an apollo-style craft (with lander & orbiter). Can land on Mun, then Minmus. then the Mun (again) and return without refueling, while not in the most efficent way. Uses lander's more efficent engines for orbital maneuvers.

The flight is in the spoiler.

Spoiler

It flies to the Mun fully assembled, redocks at a LMO, lander goes down, lands, goes up to orbit, docks. Then flies to Minmus, lands on Minmus docked, returnns to orbit. Then flies back to the Mun, lander undocks, lands, redocks. Then it goes from Mun orbit by burning Mun retrograde using all the remaining fuel from lander, some fuel from orbiter, lowering the periapsis to 40.000m, aerobrakes, then lands on parachutes.

The lander itself has (when piloted correctly) enough Dv and TWR to return from LKO and land on kerbin without parachutes and not burn on reentry.

So can the expedition go to Duna and land on Ike then return to Kerbin? KER shown ~9km/s Dv vac and ~7km/s Dv at Kerbin ASL. Nowever it can't simulate the dockings and undockings, and the orbiter has not the most efficent engines (which I can't replace with more efficient ones).

Last time I tried it, I ran out of fuel on a Kerbin return approach. But later I added a second stage to the lander.

[dire]

Hey, great question! So, you'll need about 3500 dV for Kerbin ascent, ~1000 (roughly) for Duna transfer, between 0 and 900 to circularize on Duna, between 0 and 900 to land on Duna, about 2000 to return to LDO, and around 500 to return to kerbin. Then you'll need between 0 and 1000 to circularize and between 0 and 500 to land on Kerbin.

So far, just for a Duna round trip, we're at 3500 + 1000 + 900+900+2000+500+1000 = 9800 dV to get back to LKO. Obviously, it depends a lot on how you fly, how much you aerobrake, and how much you spend on docking maneuvers, but I did include a fair bit of margin for error.

So, Duna would be questionable. You probably would make it down to Duna, but you might get lost in space on the way home.

Ike on the other hand is another matter. Instead of 2900 for a down-and-up on Ike you need closer to about 600 or 800 I think. So if you skip Duna and just do flags and footprints on Ike you should have plenty of delta-V left over. 

My advice is to try adding a top-most stage with a heat shield, and find out whether the heat shield (with half ablator) costs you at least 900 delta-V. If it does, don't bring it and do a powered circularization on your Kerbin return trip with only very slight aerobraking. If it doesn't cost at least 900 delta-V, you should bring a heat shield and use aerobraking to capture on Kerbin.

[Gapone]

Yes. The lander was not designed for atmo bodies, and I always capture on Ike on Duna intercept.

So this was my piloting.

My orbiter is packed inside a fairing, at the very top of the launch pack, just below the escape tower. (Now you will prompt me to remowe the tower.) And this escape tower is mounted on orbiter's docking port. I just don't have place to place it (pun not intended). But I have a heat shield on my command pod that is pretty tough, so I can aerobrake with just the return capsule and land.e

The bad thing is that I (in my previous flight) barely have managed to do the return intercept only to the very edge of SOI with no fuel, even RCS.

Honestly, it is overengineered a bit lot. It has 7 stages. Two of them are in a lander. Three are OP lifter, third  stage of which I used for first landing in the KMMMK (Kerbin Mun Minmus Mun Kerbin) flight. Two are attached to lander, and intended to be an (OP) transfer stage. Last transfer stage I used for the second Mun landing. The lander itself tas very little Dv, but enough to get on a Mun orbit.

Edited December 23, 2018 by Gapone

[dire]

If you want to post your craft file I can take a look at it and give you a more definite thumbs-up or thumbs-down, or if you prefer you can try this ship out, which very definitely has enough dV for Ike and back. https://kerbalx.com/direstorm/Duna-Express

[Gapone]

I'll just say that my ship is named "NOT1". Guess what does it look like.

Edited December 23, 2018 by Gapone