realistic 2.5m lko payload for apollo style mission

[Tweeker]

I'm working on a mod, and I'm trying to balance the new 2.5m engine. I've been flying it with a mk1 command pod and I kept getting to orbit with about 700 m/s Dv. So I keep adjusting the engine stats downward.

Then I realized a mk1 command pod to orbit is probably not a realistic payload. So my question is, what is a realistic (kerbal) weight for something like an Apollo style 2nd and 3rd stage?

[RoboRay]

There's a huge range of possible values, all driven by the mass of the lander. So, design the LM first.

Then design a CSM that can capture the lander into orbit around the Mun and fly back to Kerbin without the LM.

Then design a third stage that can go from a suborbital Kerbin trajectory into LKO with the CSM/LM and push them both to the Mun.

Then, last, design a first/second stage combo that get all that into a suborbital trajectory.

Only once all that's done will you know the mass. Because if you've got a tiny, lightweight lander, your 1st stage may be a tenth the size of what it would be for a big, heavy lander.

[Tweeker]

I'm not looking for a definitive answer, only an general idea of the weight range for the Apollo-type design, 3 stage, with orbiter and lander, 2-3 crew.

Not a microlight external command seat design or a giant 50 ton direct lander. Just some middle of the road designs that people are really flying. What is the combined weight of the 2nd/3rd stage of these designs at LKO or second stage ignition?

[klesh]

I just checked my current Apollo-style design. It comes in at just under 30,000kg. This is the section you're referring to?

[Guest]

Engine stats should be based around theoretical maximum Aerozine50/dinitrogen tetroxide performance. Use the isps in the game as a guide. For engine mass, base it on the thrust, using comparable engines as a gude. Don't adjust engine stats so much as the mass of other parts.

[Tweeker]

I just checked my current Apollo-style design. It comes in at just under 30,000kg. This is the section you're referring to?

http://i.imgur.com/QNHGZvx.jpg

Yes that is exactly what I was looking for.

BTW great looking ship

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Engine stats should be based around theoretical maximum Aerozine50/dinitrogen tetroxide performance. Use the isps in the game as a guide. For engine mass, base it on the thrust, using comparable engines as a gude. Don't adjust engine stats so much as the mass of other parts.

I'll keep these things in mind.

I am basing my ideas on moving from o2/rp-1 to f2/o2/rp-1

[Guest]

I am basing my ideas on moving from o2/rp-1 to f2/o2/rp-1

KSP's fuels have precisely zero properties similar to LOX/RP-1, considering they are infinitely storable, provide infinite ignitions, have thermal properties and isp similar to AZ50/NTO, and have a nebulous, inexact density. Giving an engine isps similar to LOX/RP-1 or FLOX30(or whatever percentage)/RP-1 would make it vastly overpowered. If you want that, great, I'm just pointing it out. Edited September 20, 2015 by regex

[Guest]

Here's my own Apollo-Style CSM + Lander + ALSEP + Rover. Munar sub-satellite is mounted in the Service bay.

It weighs in at 39.8 tons, not including 3rd stage of Saturn 5, for Munar Transfer.

It's launched on a modified version of this rocket: (Payload pictured does not include Rover + ALSEP)

I actually had to shrink the 1st and 2nd stages to prevent it escaping Kerbin's SOI.

That's what I came up with, although the weight and fuel are actually still more than necessary to do the job, so things could be turned down from what's in the video. Both the second and third stage have far more DeltaV than is necessary. With some modification this thing might actually make it to Duna and back, which is my plan for the future.

Anyway, I'm rambling a bit, so I hope this helps.

[Tweeker]

Here's my own Apollo-Style CSM + Lander + ALSEP + Rover. Munar sub-satellite is mounted in the Service bay.

It weighs in at 39.8 tons, not including 3rd stage of Saturn 5, for Munar Transfer.

http://i896.photobucket.com/albums/ac164/Mercenary_SPQR_CLAN/Kerbal%20Space%20Program/Apollo%20Style.png

Very nice.

I haven't flown to the Mun in quite a while, after biomes where implemented it became very repetitive. So now I pretty much by-pass the Mun in all my career games.