What radial size do you recommend for getting anywhere past Minmus?

[lefty39]

I haven't flown to Minmus yet and I want to plan ahead. What radial size do you recommend for getting anywhere past Minmus? I want to know this so I know what to research next when I get to Minmus.

[Taki117]

What do you mean by radial size? Really to get interplanetary all it really takes is careful planning. Also check out this website

[Dave Kerbin]

Radial size is up to you, it's possible to build interplanetary ships in many sizes and shapes. Granted it is sometimes easier to get them into space with large radius parts, but that is dependent on having engines like the Skipper or Mainsail.

All of these ships are designed to go to Duna (the first was from .22 when you had to return the entire experiment and included an Ike side mission, the last is from the total conversion mod Better Than Starting Manned which is basically career hardmode).

[lefty39]

What do you mean by radial size? Really to get interplanetary all it really takes is careful planning. Also check out this website

Radial size means size of the parts. Orange tanks and those big Rockomax tanks are large radial size parts.

[UmbralRaptor]

ÃŽâ€V (and by extension mass) is more important than size. It's completely possible to do impressive things with the size 1 (or even size 0) parts. Easier in some ways, given the various inefficiencies in the size 2 crew modules and engines. The size 3 engines offer impressive performance (especially for launchers), though the tankage leaves something to be desired.

edit: You're in career mode? I wouldn't bother getting anything on the propulsion branch past fuel lines. More instrumentation will do wonders.

[LethalDose]

Overall, I'm comfortable sending probes on interplanetary expeditions with 1.25 m parts, though I find it's easier to get those parts into orbit using 2.5 m launch stages, but they're not necessary. For manned IP missions, I tend to prefer 2.5 m parts, but largely because I dislike sending kebals into IP space solo.

Also, building rockets with enough delta V to go interplanetary is much easier with the new and improved joint strength.

ÃŽâ€V (and by extension mass) is more important than size. It's completely possible to do impressive things with the size 1 (or even size 0) parts. Easier in some ways, given the various inefficiencies in the size 2 crew modules and engines. The size 3 engines offer impressive performance (especially for launchers), though the tankage leaves something to be desired.

edit: You're in career mode? I wouldn't bother getting anything on the propulsion branch past fuel lines. More instrumentation will do wonders.

I agree with UmbralRaptor's first part of this, but not with his "edit" line. The propulsion branch (top line on the tech tree) will get you nukes. If this is your first play through and you're asking questions about what size parts you need to go interplanetary, I think you'll be well served by getting nukes, as you'll get a LOT more delta V out of your designs, making your life way easier. For the record though, you don't need nukes to go interplanetary (my first Duna mission only used conventional engines), but it will make your trips easier.

[Kasuha]

1.25 m is fine for all planets - the best engine for interplanetary transfers is nuclear engine which comes in 1.25 m and the 0.6 m parts are mostly not good for anything except smallest probes. The only benefit of larger radial size is that you can pack more mass into smaller length - which usually comes handy for lifters on atmospheric bodies such as Kerbin or Eve.

[cantab]

Whatever you like. Personally I often end up with using 1.25 m engines with 2.5 m tanks, usually with the flat Rockomax adapter for aesthetics.