Getting to Moho with a large ship

[spacetortoise1]

Hi, I'm trying to send a return vessel to Moho and back, but I'm running into a problem. The ship is very massive (two orange tanks, lander on the front and side tanks), although I can detach one orange tank when it runs out, the ship is still very slow, even with two nuclear engines.

My problem is doing my burn from Kerbin to Moho, whenever I set my maneuver nodes, I have to burn directly into Kerbin. This seems like it's wasting a lot of fuel, which I really don't want. Plus, the burn still takes a good half hour to complete, so that's a lot of fuel (and then I have to do an insertion burn).

Should I use engines with higher thrust? or any other help?

[Van Disaster]

Use multiple burns to raise your AP before you deorbit Kerbin, just burn for a few mins either side of where you want Pe to be. You'll need to do the same in reverse once you arrive.

[fatfluffycat]

If you could, It might be good to make a booster stage to get out of kerbin soi, and use the nuclear engines in space?

[spacetortoise1]

Awesome, that definitely sounds like my best option right now. Any tips on timing? The Moho window is very brief.

[arq]

Just start the process of raising your orbit a few days early. Make sure that you keep an eye on your orbital period (use Engineer or Mechjeb or something) so that you aren't floating far out in Kerbin's SOI with a week left to come back to periapsis when the window hits.

[Captain Sierra]

If you could, It might be good to make a booster stage to get out of kerbin soi, and use the nuclear engines in space?

This is probably the best option. A large 'kicker' stage using a skipper engine will help the burn be quicker. It isn't quite as efficient but it gets the job done in reasonable time. Use the nukes in deep space when doing alignment and inclination changes.

[Blue]

Remember that Moho's encounters, while difficult to trajectorize, are the most frequently recurring. A new window to visit Moho comes along about once every 30 days.

[SRV Ron]

Do a direct launch straight up at sunset. That will place you in a more efficient solar orbit to encounter Moho and heading away from Kerban when you do your intercept burn.. The most efficient burn would be when your orbital plane crosses Moho's tilted plane at intercept. Otherwise, it will take a lot of fuel to intercept, then get the orbit. Be prepared for long burns with the more efficient LV-N.

Universal lander in Moho orbit. The LV-N booster utilized six drop tanks.

[spacetortoise1]

Oh also here's the ship for reference. Thanks for the help guys.

The booster option might work well. I'm going to have to do some re-arrangements on my ship for it to work, but it should pay off.

Also with the Moho windows, from my experience you have to catch it at it's periapsis, otherwise de-orbiting takes ridiculous amounts of dV (usually 5000m/s with a bad encounter).

[Dkmdlb]

The Moho window is very brief.

But it comes around so often, that most people just do the transfer burn without checking for a window and set up a phasing orbit near Moho until they have an encounter.

[Khrissetti]

I've been to Moho a couple of times (but never sucessfully returned), so I learned that two or three nukes make for a very long burn.

The Honolulu has changed that.

Twelve nuclear engines!

[KvickFlygarn87]

Khrissetti: You do know you just took the effiency out of the nuclears, right?

[Specialist290]

I've been to Moho a couple of times (but never sucessfully returned), so I learned that two or three nukes make for a very long burn.

The Honolulu has changed that.

<courtesy image snip>

Twelve nuclear engines!

Yikes, that's 27 tons of dead weight right there! That can't be easy on the delta-v... You could probably also get away with leaving the RCS off of your main stage, or at least not using 3 of the huge tanks.