Complex Asparagus

[Rockhem]

How do i do asparagus with more than 5 engines, I have a rocket that is capable of taking a 50 ton payload to orbit, but i have a 70 ton interplanetary propulsion stage, and It cant take it to orbit.

So i am wondering how to do aspargaus with something more than 5 engines.

[Eleven]

The setup is the same no matter how many engines you add. Start with a center engine, add 8 engines around it. Pick one to start with and add a fuel line from it to the next one, then continue to number 4, and add a fuel line from number 4 to the center. Then repeat for the other side, so that the starting and ending engines are opposite of each other and Bam, you have a 9 engine asparagus stage.

[SciMan]

One other thing I've always found helpful is to use the symmetry option equal to how many boosters you want to drop when you stage.

I'll use a simple "one layer" asparagus setup for an example (1 center "core" stage, surrounded with 6 "booster" stages identical to the core)

There are 2 "simple" options for how to set up the staging, but they only differ by how many tanks fall off when you press space. Specifically, you can drop 2 or 3 boosters per stage.

For dropping 2 boosters per stage, set symmetry to 2x, and just copy your booster stage 3 times around your core stage.

For dropping 3 per stage, it's pretty much the same thing, except you need to set symmetry to 3x and copy the booster stage 2 times.

I find that setting up the boosters this way is very helpful when it comes to arranging the fuel lines and staging, because the game will automatically set the symmetry options to match the setting you used when placing the boosters, and the decouplers are already grouped together to drop the boosters symmetrically. The other ways that I know of use 6x symmetry for the boosters but are forced to turn off symmetry for placing fuel lines, and because all the decouplers are in the same group it becomes much harder to set up the staging correctly.

EDIT: sorry about the "wall of text", if you're only interested in standard asparagus staging you don't need to read anything below this line.

There ARE other ways to arrange asparagus staging, the most straightforward of which is simply adding another "ring" to the above example. The second ring would need to be made from 12 boosters, and attached to the first ring.

You can also experiment with adding fuel tanks to the top of the earlier stages to offset the fact that those earlier stages are feeding more engines than the later stages. Doing that means that the staging times become more similar (60s, stage, 60s, stage, etc), and it also helps keep an asparagus staged rocket's TWR near 2.0 in the lower atmosphere, which I consider to be the "butter zone" for trading gravity losses versus drag losses below 20km. Then again, YMMV and you might prefer a different TWR.

Because I use MechJeb for ascent, and because it limits the rocket to the terminal velocity, I tend to use the "add fuel tanks to boosters" method on rockets that I build that end up with a launch TWR over 3, that way the rocket stays as close to full throttle as possible in the lower atmosphere. It does drive part counts up a little (more for bigger rockets because of struts), but it does ensure that the "launcher" part of the rocket has at least enough fuel to put the "payload" part of it into orbit, and I can use whatever fuel is left to give the payload a "kick-start" for its departure burn.

Also, the fuel isn't wasted even if the payload is going to stay in orbit around Kerbin, as I have a very "thirsty" orbital fuel depot that I put there specifically to act as a "fuel vampire" of sorts, sucking any leftover propellant out of launcher stages that would otherwise end up as space junk. To prevent those stages from counting as debris, I have made a habit of putting a probe core, RTG, 2 sphereical monopropellant tanks, and a few strategically-placed RCS thrusters on the upper stages of all my launchers, that way even if I don't have any spare fuel storage capacity in orbit I can still safely de-orbit the stage (not to mention that it helps that the "victim" spent stages can pilot themselves to the "vampire" station) If/when I run out of tank space on that station, my next launch will be another empty tank module for the fuel storage station.

Doing that ends up putting solutions in place for a bunch of problems by turning them into solutions for other problems, and it does that before those "problems" can even become "problematic" in the first place! Pretty efficient, if I do say so myself.

Hope that helped you figure out Asparagus staging, and maybe someone finds the "space junk = free fuel" solution useful in their space program!

-Sci