Rotational Moment Induced Upon Radial Detachment

[SilverWolf]

I was hoping someone could help me understand what is happening here, and possibly why it's happening.  The radial attachment point is set to an ejection force of 0.  It is attached at the bow by two struts, and at the stern by two struts.  Upon detachment, a severe nose-down moment is inflicted upon the shuttle.  The red sphere is the center of gravity.

Thanks, guys.

 

[Snark]

Any chance you could post a screenshot from the other direction, so the sun is shining on the craft?  Seeing it in silhouette like this makes it practically illegible-- can't tell at all what I'm looking at.

In particular, I can't see what's attached to which, or where the decoupler is.

[Leftotian]

Judging by two fires on a black rectangle that you call screenshot, you blow your shuttle away with 2 SRBs.

[SilverWolf]

I'm so sorry about that.  I went and committed the cardinal sin of taking screenshots into the sun.  >_<  Here you go.

[bewing]

So when the sepratrons push the tank away from the shuttle, you need to relight the engines? So you need to be pointing the right way?

I think I see your decoupler against the mountains -- just move it forward a couple meters, directly under your shuttle's CoM.

I'm going to guess that it's misfiring -- that is, it's decoupling with some force, even though you set it to zero. If you put it at the CoM, you won't get a rotation.

 

Edited August 3, 2016 by bewing

[SilverWolf]

It sits right on the Shuttle's CoM.

Removed Separatrons, removed problem.    Why?  So I can't have the ET pushed away from the shuttle?

Edited August 3, 2016 by Verran

[Reactordrone]

I suspect the thrust from the separatrons is hitting the wing and applying a force to them. You should still be able to use separatrons but they'll have to be angled to prevent the exhaust from impinging on the shuttle structure.

[SilverWolf]

I didn't think I'd actually have to account for that.  Let me give it a go, and I'll be back with you in five minutes.

Well, if that's what's doing it, I'm kind of up the creek, because I just angled them out by about 45 degrees, and that still upset the shuttle.

Edited August 3, 2016 by Verran

[bewing]

1 hour ago, Verran said:

So I can't have the ET pushed away from the shuttle?

If the decoupler is really at the CoM then give it a little bit of force. Then you won't need the sepratrons for pushing the ET away.

 

[SilverWolf]

Reactor drone was on to something.  Cranked the Ejection force back up, and moved the separatrons closer together so that the aft ones are directly under the Orbiter's CG.  Minimal moments.  Thanks, guys.

[Pecan]

What is this mod I wot not of, that shows CoM in-flight?
(Bet I'm going to feel daft for this and am probably already using it but didn't know that function).