Should this get me to Moho and back?

[spacetortoise1]

I spent a while re-building my entire Moho ship and got this. The total mass is 135 with full fuel.

It features one skipper engine as a booster stage (it will drop when empty), then two nuclear engines for maneuvers.

The lander should be a piece of cake, it will undock, land, rendezvous and re-dock with two kerbals inside.

If it gets me there, any suggestions on maneuvers?

[Umlüx]

looks a lot like my first manned moho vessel. one orange tank with 2 LV-N and a small lander.

it failed because i wasnt able to slow down to get into moho orbit...

[Technical Ben]

Possibly. Launching from Moho is hard because it has a lot of gravity. So careful you don't burn it all up on approach, else you'll be sending the main section of the craft to rescue the kerbals, as I did!

[spacetortoise1]

Yeah, that's a big concern. The lander should work great if it has enough fuel, I tested it on Kerbin and it can get pretty high up and it goes very fast.

[Kosmo-not]

Why all the solar panels?

[DMagic]

Does that lander have four engines and four RCS tanks? That is a lot more than necessary for a Moho lander. Here is my Moho lander (the rover was launched separately):

It has a single LV-909, a single, double-height fuel tank, and one of the small radial RCS tanks. That was plenty to get from a 100km orbit to the surface and back. If you aren't confident about docking you might need a bit more RCS fuel, but you definitely shouldn't need 400 units. And the 2-man lander can has plenty of torque, that additional reaction wheel probably won't help.

The mothership should be fine as long as you can get the intercept setup up decently well. You can always switch to the NERVAs early if you think you are running low on fuel.

[Captain Sierra]

It should, but I might consider sending a fuel tanker too, just in case. If you don't need it, you could always just deorbit it onto Moho.

[capi3101]

I'm'a gonna go with yes, as long as you don't ever light that Skipper. If you do, it's a solid maybe...

It does seem like it's got a bit more RCS than it needs. Solar panels too - you could easily trade out those four Gigantors for a pair of dinky little 2x3s without the cases and be fine. Better yet, 4-8 OX-STATS down there towards the Skipper would keep you covered; a ring of tiny batteries could also be added and you'd still have less overall weight than those four Gigantors. Strike that - put 'em up on the other orange tank; I see the docking port setup there.

You might want to lose the Skipper, did I mention that already? Not because you won't need its thrust, but because I'm pretty sure it's setup to drain that other orange tank first (unless you disable fuel crossfeed across the docking ports).

What's your overall mass?

[spacetortoise1]

I'm'a gonna go with yes, as long as you don't ever light that Skipper. If you do, it's a solid maybe...

It does seem like it's got a bit more RCS than it needs. Solar panels too - you could easily trade out those four Gigantors for a pair of dinky little 2x3s without the cases and be fine. Better yet, 4-8 OX-STATS down there towards the Skipper would keep you covered; a ring of tiny batteries could also be added and you'd still have less overall weight than those four Gigantors. Strike that - put 'em up on the other orange tank; I see the docking port setup there.

You might want to lose the Skipper, did I mention that already? Not because you won't need its thrust, but because I'm pretty sure it's setup to drain that other orange tank first (unless you disable fuel crossfeed across the docking ports).

What's your overall mass?

135 total mass with full fuel. I'll disable the crossfeed from everything except the tank the skipper is attached to. The solar panels are mainly for aesthetics, I guess I didn't need that many gigantors.

[capi3101]

135...okay. 1 orange tank + 4 FL-T800s; you've got 90 tonnes of fuel tanks, that weighs 10 tonnes empty - 80 tonnes of fuel total. So the dry mass there oughta be 55 tonnes, right?

ln(135/55)*9.81*800 = 7,047 m/s delta-V.

5560 is what the delta-V map shows - that's 1680 for a Kerbin/Moho transfer, 2200 to go into a low orbit, and 1680 for a transfer back. You've got that, no doubt. Thing is, I've never seen alexmoon's calculator show less than 4500 m/s for a Moho transfer - both ways that's 9,000 m/s at a minimum. So I'll have to stick with "maybe". You should be able to make it there but I can't guarantee you'll make it back without a refill in Moho orbit.

[spacetortoise1]

That's always an option, I'll send a fuel tanker or two directly behind it, just in case.

Thanks!

[Moar Boosters]

I wouldn't get ME to moho and back, but you might be better at setting up maneuver nodes.

The main difficulty I find is slowing down to orbit Moho once you reach it's SOI. 2200 to get into a low orbit is WAY less than it took me. I was closer to 4k. You're only in it's SOI for a short while as well, so you need a bit of TWR to slow down in time, before you go flying out of its SOI.

[Moar Boosters]

I wouldn't get ME to moho and back, but you might be better at setting up maneuver nodes.

The main difficulty I find is slowing down to orbit Moho once you reach it's SOI. 2200 to get into a low orbit is WAY less than it took me. I was closer to 4k. You're only in it's SOI for a short while as well, so you need a bit of TWR to slow down in time, before you go flying out of its SOI.

Personally I'd send a whole fleet of fuel tankers