Did I over complicate this craft?

[CrazedGunman502]

It's capable of reaching Jool with very little fuel left in its lander stage. What should I add/remove to make it capable of reaching Jool with some fuel to spare?

(Click to make it bigger)

edit :

Thanks everyone, I did manage to do a successful eve and return mission with your advice.

http://imgur.com/a/fqkYe

Going to try a laythe and return next.

Edited October 28, 2013 by CrazedGunman502

[epima09]

I'm not an expert.

But that does seem overcomplicated.

[lammatt]

ask yourself this,

why are you using skipper after leaving the atmosphere,

if you managed to answer this, u will be able to make your ship a lot lighter and capable of going a lot further

[lammatt]

in case my previous suggestion wasnt clear enough,

use nuclear engine for the ejection and injection

[UmbralRaptor]

Looks like a classic case of too much thrust, not enough fuel. I'd look into giving some of those mainsails 2 orange tanks, or replacing them with skippers. Also, that's... a lot of boosters.

[FlamedSteak]

I think you're going about it the wrong way. Consider multiple launches and assembling and refueling your craft in space.

Generally I'll launch a large Nuclear powered booster pack into space, then launch my lander, then rendezvous and dock. Then launch a refuelling ship, get them both topped up with juice then start the mission

Also boosters are great for getting you to orbit, but using them for interplanetary burns isn't the most efficient way of doing things.

[SkyRender]

Holy guacamole is that thing overkill! The old saying "more is less" comes to mind when I look at that. Try setting up asparagus staging and more efficient engines instead of using all of those Mainsails and massive stacks of fuel. A good standard setup that will get a decent-sized payload to orbit is 3 sets of 2 asparagus-staged orange tank + Skipper boosters strapped onto an orange tank + Skipper. Stick a Rockomax-32 above that with some side-mounted LV-N engines, and then your lander on top of that, and you should have a ship that can reach Jool with fuel to spare... as long as you get the launch window right and don't muck up the take-off too badly.

[CrazedGunman502]

I forgot, I did replace the skippers with nuclear engines some time ago, old screenshot. I gave a go at replacing the mainsail under the orange tank (at the tippy top) with three nuclears aswell, but even with three, they just aren't strong enough. Any alternatives?

[SkyRender]

Knowing the purpose of your craft would help a lot. I'm guessing you want to send a craft to Laythe and possibly return it to Kerbin afterward?

[CrazedGunman502]

Looks like a classic case of too much thrust, not enough fuel. I'd look into giving some of those mainsails 2 orange tanks, or replacing them with skippers. Also, that's... a lot of boosters.

Yup, found myself running out of fuel pretty quick. Will report later with results.

[SkyRender]

Yup, found myself running out of fuel pretty quick. Will report later with results.

I've built you a craft that should be more than adequate, as long as you pilot it well. You can find it here. If nothing else, take a look at the design principles behind it.

[Kerbol Prime]

Try following the philosophy: Less engines, more fuel.

[Lojik]

when building your craft consider the ISP of the engines and what stage they will be at when firing

another factor to consider is your gravity turn, when are you turning, is it too early or too late? 10k up is a good starting point to start your gravity turn.

what about orbit height when burning for Jool, have you considered a higher or lower KO before burn, are you burning to Jool at the right time to conserve Dv?

do you use something like Kerbal Engineer to know your Dv of the entire craft before lift off?

Edited October 25, 2013 by Lojik

[CrazedGunman502]

-snip snip

Double post

Edited October 25, 2013 by CrazedGunman502

[CrazedGunman502]

Found out that if my rocket had asparagus staging, it would be 20000000000% More efficient. (Did I do that right?)

Yes so.. I've been trying to figure out asparagus staging with my rocket and it is NOT going well.

If you would like to quickly Asparagify it that would be great. (Never Again)

http://www./download/hxmlfivxzfn1m4u/The_Orbiter_-_V14.craft

[numerobis]

One does not ... simply... asparagify a rocket.

Start from scratch, and start from the top down. Build your payload as light as possible, then give it propulsion. Then give that some propulsion, etc. Repeat until you have the delta V you needed. Atmospheric stages should be in the range between TWR 1.5 and 2.5 (i.e. start at 1.5, then reach 2.5 when it runs out of fuel, remember this is thrust to *weight* ratio, which depends on what planet you're on), the closer to 2 the better. Higher stages can be much lower thrust, which saves you engine mass.

[SkyRender]

It'd be better if you learn how to do it yourself, actually. Asparagus staging has a very basic concept behind it: all of the lower-stage engines fire at the same time, but they're all rigged in such a way that they will run out of fuel and be dropped in sequence.

It's best to build your asparagus staging backwards: start with the tanks that will be dropped last. Just feed the fuel lines from those tanks into the central tank, and make sure that the first stage has both the central engine and those new side engines set to fire, with the two decouplers for the side tanks set to drop next in the staging list.

After that, copy (shift+click) the first set and place a new set a ways off to one side of it but also attached to the central tank. Grab its fuel line and feed it into the first set of asparagus rockets, and then use the highlighting of radial decouplers when hovering over the icons in the staging to determine which set is the newly-added one. Once you've identified it, add a new stage below the stage that has both sets of radial decouplers in it, and move the new set into this new stage.

The third set of asparagus tanks are copy-pasted from the second set and need even less maintenance; just place, add a new stage for them, and move the radial decouplers into that new stage so they're set to fall first. After that, strut it up (tip: fuel lines act as struts, and bracing works best if you do at least 3 sets radially plus one strut array coming down from above to join the tops of the tanks to the central stack). And that's a textual guide to asparagus staging! Check out the craft I uploaded if you want a visual reference on how it should look when you're done.

[CrazedGunman502]

One does not ... simply... asparagify a rocket.

Start from scratch, and start from the top down. Build your payload as light as possible, then give it propulsion. Then give that some propulsion, etc. Repeat until you have the delta V you needed. Atmospheric stages should be in the range between TWR 1.5 and 2.5 (i.e. start at 1.5, then reach 2.5 when it runs out of fuel, remember this is thrust to *weight* ratio, which depends on what planet you're on), the closer to 2 the better. Higher stages can be much lower thrust, which saves you engine mass.

So basically you're saying that my hopes of reaching Laythe are crushed? x_x

[SkyRender]

So basically you're saying that my hopes of reaching Laythe are crushed? x_x

With that rocket, at least. One of the most important rules of rocket design is to never be afraid to start over from scratch if something's just plain not working out.

[Bothersome]

I think you need think through the mission BEFORE you head out. Figure out what your goals are, write em down, then build to meet those goals. Of course experience in each part of the mission helps but you gotta start somewhere.

Take a look at this mission to Tylo and Laythe story I wrote up some time ago. It should give you a little more understanding what you might need to plan for.

Then you might ask for help on how to do certain parts of your mission and be more likely to get help that's not so general.

[Levelord]

The NERVA engine placement confuses me. I don't see any decoupler to disconnect it from the lander, so I can only assume you'll be landing with the NERVA engine attached, which negates the point of having landing legs, since they won't reach the ground...

[lammatt]

agree with the ones who say you should build according to your mission.

say for eg, you want to go to eve, and you checked the dv budget you need, and you build your lander, interplanetary transfer, lifter accordingly with respective to dv requirement of each orbital maneuver

and, a few hundred m/s of dv to spare in every stage is a good idea, since you are never gonna do a perfect maneuver that uses barely the theoretical minimun dv, there's alway some extra steering loss

[KvickFlygarn87]

Holy scubiduweebapapow, yes, yes you did overcomplicate it.

NUKES.

[The Destroyer]

I agree with Sky Render, sometimes when something dosen't work- start over.

Build a better rocket. And what's with all the boosters? You know the saying "MOAR BOOSTERS" isn't always good... Right?

[Sirrobert]

Well...

It's a very Kerbal like rocket. I'm sure Jebedia would be proud