Unstable solid fuel boosters

[Dunger]

I am having a problem with mounting my solid fuel boosters. They wobble if I only attach them with 1 decoupler. When I add another decoupler or more it still only attaches to one. The boosters are always unstable. Anyone know what I'm doing wrong.

[Streetwind]

You can use struts (a part found at the top of the Structural tab) to stabilize the boosters. Attach the strut from the tip of the booster to the core of your rocket.

If you attach a SRB to a decoupler near the top of the SRB, that's a very unstable configuration. Have the decoupler halfway up the booster. Or, have it down at the bottom while using a strut to stabilize the top.

Additionally, try to avoid control authority on the side boosters. Meaning: if it has a gimbal, turn it off. If you have fins attached, remove them. Attach fins to the core stage if you feel you need some.

[Dunger]

Did the job nicely. Thanks.

[magnemoe]

On 3/22/2023 at 5:00 PM, Streetwind said:

Additionally, try to avoid control authority on the side boosters. Meaning: if it has a gimbal, turn it off. If you have fins attached, remove them. Attach fins to the core stage if you feel you need some.

Now this is new from KSP 1, there if launching something with large SRB like the SLS I would not need fins anymore then they burn out so I put them on the SRB. 

[Streetwind]

Nah, this is advice straight out of KSP1.

But that doesn't mean that you can't ever have fins on your side boosters. This is KSP, we can build whatever we want   I'm just saying, if your side boosters wobble, and you want them to stop, and you have fins on them, try removing them to see if that helps.

[Mahnarch]

I usually attach the radial decouplers toward the top of my onion stages and boosters so the decoupler pushes their bodies away from the core - and I attach the struts to the bottom.

Whenever I put the decouplers near the bottom of them they always fall in, towards the core. Then, fire happens.

Edited April 4, 2023 by Mahnarch
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