I am trying to send multiple satellites in space at the same time. The satellites medium-sized and they need quite a bit of fuel so I want them to be radially attached to the main part of the rocket during ascent.

The problem is that if I attach the satellites to the radial decouplers, after staging, the decoupler will stay attached to the sattelites. This is not desired because, not only that useless mass is attached to those sattelites, but the center of mass is a bit off-centered, making the satellite harder to maneuver.

I want the radial decoupler not to be attached on my satellite payloads when I stage, but I really don't know how. It doesn't matter where the decoupler itself ends but I don't want it attached to the payload.

I tried the following:

• Change the orientation of the radial decoupler to face the main part so that it might be attached to the main part after staging. It didn't work.. for some reason it still remained attached to the payload.
• Try to put two radial decouplers one over the other (and facing against eachother, just like you can do with the stack decouplers). Doesn't work.

Eventually I ended up putting yet another decoupler on the other side of the payload/satellites so that even if the added mass doubles, at least the center of mass won't be off-centered anymore.

Is there a solution to this? Thank you!

3 Answers

1. Build your satellite (only the satellite).
2. Put your favourite radial decoupler on it.
3. Put the part you want to attach it to on the decoupler.
   • If you're not sure what part that will be, or you want multiple satellites on the same part, just use a cubic strut.
4. Grab the re-root tool.
   • 4 on the keyboard, or upper-left of your viewport, looks a bit like the letter Z.
5. Click a couple of times on the part added in step 3.
   • It's weird in that you might need to click twice for it to take effect, pay it no mind. :)
6. Grab it by the part added in 3 (the whole vessel should move), and save it as a subassembly.
   • It's somewhere in the part selector. You might need to expand the advanced tools at the very upper left of the toolbar.
7. Load up your rocket and attach the new subassembly to it.
8. Your satellite is now attached with a reversed radial decoupler.

Admittedly, I haven't done this for a couple of versions, but it should probably still work. :)

1

As far as I know, it's impossible to achieve what you're asking with radial decouplers; however, the TS-series stack separators do exactly what you need for a vertical configuration: they neatly separate both stages they're attached to, and don't stick to either of them.

Consider switching to satellites stacked on top of each other, rather than radially attached to the lifter stage. This solution would also let you use a fairing to provide a more aerodynamic shape to the satellite stack during atmospheric ascent.

Why not just use in-line decouplers instead?

1. Attach a cubic octagonal strut to your main part, using the appropriate symmetry mode. Rotate it so that one of the attachment nodes on the strut faces outwards. (Any other structural part that can attach radially and has attachment nodes of its own will work, too, but the cubic octagonal strut is the smallest and cheapest.)

2. Attach a small stack decoupler / separator to the strut, and then attach your satellite to the decoupler / separator. (Note that you will need a free attachment node on the satellite, but that's usually easy to arrange. If all the available nodes are in awkward places, you can always use the rotate and translate tools to move the satellite after attaching it.)

Alternatively, to reduce part count and drag at the cost of slightly higher mass and, well, cost, you can use a single docking port instead of the strut + decoupler combo. Just attach the docking port radially to your main craft, and then attach the satellite to the docking port. You may also want to right-click the docking port and select "enable staging".