Critique my Duna Mission!

[Boots]

Hi there! New to KSP, started with 1.0. Have landed on Mun and Minmus several times, opened most of the tech tree, put multi-part stations in orbit round all bodies in the Kerbin system and sent unmanned probes to Duna and Ike. Now it's time for a manned mission. That's where I need your help.

I've built the below rocket based on an Apollo-like mission profile - orbital rendezvous around Duna with separate landing and return stages. Basically there are

Stages 1 and 2: asparagus staging in two pairs, 4x Mammoth

Stage 3: central orbit stage, 1x Rhino. Combined Dv in Stages 1-3 = 4599m/s

Stage 4: transit stage, 1x Rhino. Transit Stage Dv = 2591m/s

Stage 4 contains the following components:

- A science pod containing the science bits too heavy to bring home easily, ie the Science Jr. and Mystery Goo. Equipped with 2x parachutes. Does not need to return to orbit. Dv = 999m/s

- A lander, crewed by two Kerbals and equipped with a pile of science components for surface exploration and 4x parachutes. Needs to make planetfall and return to orbit. Dv = 2274m/s

- The command & return module. Should be able to make LDO without expending any Dv (that's the job of the transit stage), so just needs to return to LKO, where it will dock with my orbital station. Dv = 2181m/s

Pics:

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My questions for you, spaceship gurus:

- Does each component have fit for purpose Dv?

- Will the lander be able to land and take off again with only one lowly LV-909?

- Will the Command module be able to get back to LKO from LDO with only 2181m/s?

- Is the separate Science Pod idea a good one, r will it just mean a lot of boring walking for my Science Officer?

- Related, should I include a rover, or is that just deadweight?

- Could I put wheels on the science pod maybe?

Any help appreciated!

[H2O.]

Numbers indicate that it should be OK, although if I were you, I'll use what is left on the transit stage to do your Duna descent, and I'll drop the parachutes on the lander (heavy and inefficient on Duna).

Oh and you have way too much RCS (you don't need any on the lander, and you could easily halve the quantity on your command module).

Edited May 19, 2015 by H2O.

[Boots]

Numbers indicate that it should be OK, although if I were you, I'll use what is left on the transit stage to do your Duna descent, and I'll drop the parachutes on the lander (heavy and inefficient on Duna).

Oh and you have way too much RCS (you don't need any on the lander, and you could easily halve the quantity on your command module).

Thanks, I'd never have noticed, and the lander is nimble enough without them.

[H2O.]

Yeah, mono-propellant is so heavy. Carrying too much mono-propellant has an important impact on your delta-v budget. Removing it is usually the simplest way to share weight out of a design: ditch 3/4 of your mono-propellant (don't forget that there is mono-propellant in the lander can too).

Glad I could help!

[Prof. Endwalker]

I would say you should decrease the amount of monopropellant, which will then allow for less launch power needed, so it should be light and cheaper. Overall is looks great! Welcome to the Forums!

[MessyMix]

Every ounce of weight is going to affect the amount of fuel you carry to lift it, and the amount of fuel to lift the fuel, and to lift that fuel, etc. etc. so by tuning down how much is in the last few stages and then refining the Kerbin ascent stages you can make your design much more efficient. You probably know this already, but just a heads-up, and follow the suggestions above, I guess. Gud luck

[Boots]

thanks guys.

I removed all but two small tanks of monoprop from the command module. I also ditched rcs and mono from the lander entirely, realising it could rendezvous with main engine, orient with reaction and then let the command module do the docking.

Will tweak the lifters next, but having a little spare Dv can never hurt in KSP, right?

I also went back through all my other designs and halved the mono in them!

[Solarapple]

Nice job! I really like the science pod and service bay idea. Pretty new, though maybe not as impressive as packing in years of science in one service bay (credit to a redditor: http://i.imgur.com/I4ry59F.jpg ), but it's pretty good. Though I do suggest to edit your config a bit because the 1.0.2 aero is a bit.. soupy. In other words, entire stations will survive reentry (except for hitting the ground), and shuttles touch down at 25 m/s. Of course, the 1.0 atmo (what I'm using now) is, IMO, a bit too light since you can lift around 60-100 tons into orbit with 3 of the tall kerbodyne tanks and one of the 3.75 m 4 engine cluster kerbodyne engines. But hey, I also started halfway through .90, and I've only been on the Mun, Minmus, Duna, Ike, Dres, and Gilly (I returned a kerbal from all of them except gilly), so take this with a grain of salt. Also, I like how you used a Soyuz-style rocket for an Apollo-style payload.