Question about staging properly

[Kevlarburrito]

I am trying to setup a stage where I use a main engine and SRBs at the same time, then when the SRBs use up their fuel, they get jettisoned. The problem I am having is that when I jettison them, it separates the whole stage, and not just the SRBs. Is that something I have to setup as an action group, or does it have more to do with how the stages are configured?

Edited November 26, 2014 by Kevlarburrito

[Starman4308]

Staging error. Make sure the SRB decouplers are in a stage before the main engine decoupler.

And while KSP tries its best to set up a good staging order, it usually fails horribly. Always manually inspect and reconfigure your staging.

EDIT: Look at the stages in the lower-right. The first one will decouple SRBs and the Mainsail at the same time, while the second one has had the Mainsail decoupler moved one stage up.

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Edited November 25, 2014 by Starman4308

[Red Iron Crown]

First, make sure you remembered to use radial decouplers for the SRBs. If you already have them, it sounds like you need to add a stage and put the decoupler for the main stage in it alone. This stage should be above the stage with the radial decouplers for the SRBs.

Shouldn't need action groups, this can be done entirely with staging.

[Kevlarburrito]

Ah that makes much more sense, thank you both!