Nerv nukeclear engine efficenity

[Aidan likes minmus]

so I plan on creating a interplanetary drive to duna I also intend to bring it back, I intend to put maybe 2 or 3 landers, with some crew space( a hitchhiker) and a mobile lab. with all of this load what would be a good size of jumbo fuel tanks or the smaller 32 half ones?.

[Geschosskopf]

What does MJ or KER tell you? Without knowing the payload mass, there's no way to tell you how much fuel you need and whether or not 1 engine is better than another.

[Aidan likes minmus]

I don't have thoses mods

[fchurca]

You can eyeball it summing the weight of the heaviest parts according to the weight in the part descriptions

[ajburges]

You can also get current craft weight in VAB/SPH with a popup on the bottom right.

Get your payload (cabins, support systems, recovery, auxiliary craft, and landing fuel) built, note the weight, and consult the optimal vacuum engine chart for .3 or .4 TWR to find the mass optimal engine for the dV you want.

If you want to just reckon it, the break even point for nukes vs chemical is about 5t of fuel (that is 1000 units of LF) per NEVA engine. More fuel per engine and nukes will probably be mass efficient, less and you may want to explore a chemical design.

Note this is to optimize mass. If you make a multi-mission reusable tug. NEVA economics comes ahead quicker. The economics of reusable craft is dominated by consumables.

My plan for Duna is to repurpose a crew liner I'm building for Minmus station and tourist contacts. It's first mission will be to tug tourists and a lab station to Minmus, skirt Kerbin SOI for experience, fly by Mun for a tourist contact, and return to LKO for refuel, crew cycle, and attachment of the Duna mission module.

Edited June 19, 2015 by ajburges