First Jool mission, how to start?

[lordmuffin]

I'm thinking of doing an interplanetary mission to Jool and it's moons on my Sandbox save, so how do I go about it?

I know I have to use some kind of nuclear rockets, but that's about it.

[Pecan]

Second star to the right and straight on 'til morning.

[Pecan]

And if THAT's not giving it all away:

1. Find out when the planets are aligned for a transfer window
   
2. Decide what you actually want to do
   
3. Find out how much deltaV is required
   
4. Design ships to fulfill the mission profile
   
5. Build them
   
6. Fly them
   

It's rocket science, you see. "Some kind of nuclear rockets" are not required, but are the most efficient engines.

Beyond that you'll have to give us a bit more of a clue as to what you want advice with. Or read the tutorial in my signature

[lordmuffin]

And if THAT's not giving it all away:

1. Find out when the planets are aligned for a transfer window
   
2. Decide what you actually want to do
   
3. Find out how much deltaV is required
   
4. Design ships to fulfill the mission profile
   
5. Build them
   
6. Fly them
   

It's rocket science, you see. "Some kind of nuclear rockets" are not required, but are the most efficient engines.

Beyond that you'll have to give us a bit more of a clue as to what you want advice with. Or read the tutorial in my signature

Mainly what I want advice with is BUILDING the craft, I'm good enough with transfers.

[Norpo]

I went there with a mothership, lots of gravity assists, and a small lander docked to it. I had "planned", if you could even call it a plan; to land the lander on Pol, Bop, and possibly Vall. I went there without a plan, just doing a hohmann transfer when the time was right and improvising from there.

I accidentally trashed my lander on Bop. Probably going in without a plan wasn't the greatest plan (or lack thereof), I zigzagged a lot. The mothership did eventually enter the SOI of all the moons, though.

Anyways, if you're going to use gravity assists (you should, saves a ton of delta-v), download PreciseNode if you don't already have it. Seriously. That thing is a lifesaver. Even if you don't go to Jool, download PreciseNode.

And yes, nuclear engines are a good idea, I used them and I barely had enough fuel to get back, if I hadn't used them i'd probably be stuck in Tylo orbit or something.

EDIT: Building the mothership is basically sticking an orange tank onto a command pod with some nuclear engines stuck to it. (WITH SOLAR PANELS) Then, having some way to attach a small lander to it. Landing on moons, then returning to the mothership to transfer everywhere and refuel was the plan, but as you probably read, I trashed my lander on Bop, so I didn't get much of a chance to refuel.

Edited December 7, 2014 by Norpo
forgot the solar panels

[Pecan]

Mainly what I want advice with is BUILDING the craft, I'm good enough with transfers.

Righty ho, that gets us a lot further. Cartographer Heavy (unmanned), chapter 5 of the tutorial, Tractor Light, chapter 7, and Landers Light and Medium from chapter 8.

Otherwise ... again, work out exactly what you want to do. Just there (un)manned (and back), or visit moons, land on them, re-orbit?

My preferred (crewed) approach is to use tractors rather than single-use vehicles all the way from KSC but you may not want to do that.

As with any design, working backwards, I'd first make sure the tractors can get back with all the crew. Then add fuel so it can get there in the first place, dragging landers if required. And get them into the right positions for landing/re-docking.

Once you've got all those bits and pieces consider how you'll launch it in the first place - and design the launch vehicle(s) necessary. Single-launch or multiple with orbital construction/docking (better, in my opinion).

[Richy teh space man]

What you could do is a larger vessel that sends off small probes to orbit the moons, and maybe even do a parachuted landing on Laythe..?

Is this manned/unmanned?

More info needed..

[cantab]

As said, start by deciding what exactly to do. It's probably best to focus on just one of its moons (or Jool itself, if you like) if it's your first mission.

Then work out your delta-V needs. For the Jool system this is a little more complex than most, and simple delta-V maps often give values that are way too high. These charts http://www.reddit.com/r/KerbalAcademy/comments/1qu5jv/deltav_charts/ are the most comprehensive I've found. In particular, you have two possible "simple" routes between Kerbin and any of the Joolian moons: you can either go directly to/from the moon, or you can go via a low pass of Jool. Depending on which moon and which direction one or other may require less delta-V.

Then build your ship to meet the appropriate delta-V requirements, plus a margin for safety, and also to have sufficient TWR.

Then fly it. Basic interplanetary transfer is well covered elsewhere. I'll add the advice that in order to get or avoid getting a moon encounter on your way through the system, set up a mid-course correction on your way between Kerbin and Jool and use a combination of pro/retrograde and radial on the manoeuvre node. This allows you to alter your time of arrival at Jool, and thus whether or not you'll meet a particular moon, while keeping your Jool periapsis the same.

(That same technique, by the way, is how you can avoid Ike.)

[panzer1b]

Just make a barebones vbasic SSTO and go to laythe while ur at it.

cant believe i got to laythe in something that was designed for looks above all else, and yet had teh dV to get to laythe and LAND!

[Mistake Not…]

Alex Moon's Launch Window Planner is fantastically useful for figuring out interplanetary missions. Some of the numbers will be a bit impenetrable - the date and required delta-V are perhaps the most useful. Wiggle around a manoeuvre node until you get an encounter - the Precise Node mod mentioned above is very useful too. Oh, and Kerbal Alarm Clock. Have your long duration missions still running while you get busy on shorter ones, with reminders popping up when they need attention...

[bsalis]

Without knowing what you want to do there I would suggest a high-dV single stage craft with the nuke engines. Have the launcher get that craft into a transfer to Jool fully fuelled (or close enough). Then plan and explorer the Jool system when you get there, as your dV allows.

Small tip: you can EVA to surface and back to orbit on Bop and Pol to save fuel. Though Pol is cutting it fine.

[Boris_T_Roach]

For any Jool mission (whether its career or sandbox) I build in LKO....

1 fuel tanker consisting of 3 orange tanks in a string, 2 x32 fuel tanks that can be dropped when they empty, and 3 nuke engines attatched to the middle orange tank via short griders and F400 fuel tanks, dont forget some docking ports either

The crewed ship is generally 2 or 3 hitchhiker pods connected by the multinode connectors, a laythe capable lander on the front, several probes/rovers attatched to the node connectors and all pushed by 3 nuke engines in an arrangemnt like the tanker.

Flight plan is tanker leaves first, when it arrives at Jool, it aerobrakes at Laythe for Laythe orbit, the crewed ship goes at the next transfer window, it arrives at Laythe nearly empty of fuel, and refuels.. then goes exploring.

Watch any orbits that intersect with Tylo, they can get fairly hairy. and have fun

[SlyReaper]

Just make a barebones vbasic SSTO and go to laythe while ur at it.

cant believe i got to laythe in something that was designed for looks above all else, and yet had teh dV to get to laythe and LAND!

Landing it on Laythe isn't too difficult, the trick is doing that and getting it safely back to Kerbin as well. I've done it once, but only by having fuel depots in orbit around both Laythe and Kerbin. Also, finding a safe landing strip on Laythe is surprisingly hard, I found.

The normal way I do Laythe landings and returns is to construct my spacecraft in two parts. A big fuel tank with nuclear engines at the back goes up first, then I launch the lander module and dock to it. Video of one of my early attempts last year:

. Yes, I abuse the hell out of asparagus staging.

[Frank_G]

Before going to Jool for the first time, i watched lots of space docus (BBCs Journey to the planets f.e.), sci fi movies like 2010 and read some stuff on wikipedia. There i got some basic idea, what i would need. Going to Jool was the most fun mission i ever flew and designing the craft was a great part of that. You can take a look at my voyage diary in my signature if you need some inspiration.

[FlyingPete]

I'd build several smaller ships (easier to handle during transfer burns) and rendezvous either around Laythe or in a low Jool orbit. From here you can send individual small craft to visit the moons. That way you can design specific craft for the differing conditions- landing on Bop will require a completely different craft to Tylo or Laythe, for example. Leave the space station/landers in orbit and bring the crew home in a small return vehicle to save on fuel. Brotoro's excellent 'Long Term Laythe' series should give you a few ideas.

[Cmdr. Arn1e]

Check out the Jool-5 challenge - lots and lots of ideas going on there, as it's a do-all-5-moons-in-one-mission you might want to scale back from them if you only want to do one moon!

[Death Engineering]

It's even more satisfying doing a Jool mission without 'nukes.

[SlyReaper]

It's even more satisfying doing a Jool mission without 'nukes.

Yeah, use ions. You can use jetpacks to land on Pol and Bop.

Edited December 8, 2014 by SlyReaper

[The Minmus Derp]

Maybe do a really big (when i say really big i mean REALLY BIG) mission that has probe orbiters and landers for all the muns and maybe an atmospheric probe to jool.

[Foxster]

For the first trip I'd plan a flyby of all the moons. 

The easiest craft is "some" nuke engines and LF drop tanks. Take more dV than you need to allow for unfavorable orbit changes. 

When approaching Jool for the first time, set up a maneuver node and play until you can get a gravity assist from one of the inner moons to save a huge amount of dV slowing down.