Sepratrons alter the rocket's center of thrust, why ?

[Macmads]

Hello,

I succeeded at elaborating a command module that can land (on Kerbin) smoothly without any 'chute using sepratrons. Cool enough. But, this setup alters the COT of the whole rocket without any apparent reason. If i remove the said sepratrons, everything comes back to normal.

I acutally use moded CM and sep's, but the issue does not seem to come from the community coding, as you can see :

Whatever is put underneath doesn't change anything.

I tried several setups; short rockets, tall, lined, clustered, fairings. It seems I can't manage to straight it up. Those 6 little besterds won't give up at annoying me.

Has anyone gone through this issue?

Edited July 6, 2015 by Macmads

[Mic_n]

If it's just a matter of the cosmetics of it, right-click and empty them of fuel while you're checking it out (just remember to refill them before launch). No fuel = no thrust, and no thrust = no impact on CoT display.

If it's actually producing weird thrust like that, then it sounds like something's broken symmetry-wise. Check they're actually placing, and there's nothing weird going on with either that fuel load or thrust limiting.

Edited July 6, 2015 by Mic_n

[Technical Ben]

Older versions had slight rotation/angle errors on pointed modules/tanks/parts, such as the command pods. Can you see if it works properly on cylinder tanks/pods?

[edit]

Testing myself, it appears cylinders are fine.

With some predictions/data output from MechJeb in addition to testing, I would say currently a strange "veer left" atmospheric/drag/lift aero model bug seems to have kicked in for any parts that had lift. Hence the cylinders being excluded. :/ ???

However, this appears to be the readout effected only, and the craft/engines all fly/fire straight/true.

PS, move to bug forum?

Edited July 6, 2015 by Technical Ben

[Macmads]

Older versions had slight rotation/angle errors on pointed modules/tanks/parts, such as the command pods. Can you see if it works properly on cylinder tanks/pods?

[edit]

Testing myself, it appears cylinders are fine.

With some predictions/data output from MechJeb in addition to testing, I would say currently a strange "veer left" atmospheric/drag/lift aero model bug seems to have kicked in for any parts that had lift. Hence the cylinders being excluded. :/ ???

However, this appears to be the readout effected only, and the craft/engines all fly/fire straight/true.

PS, move to bug forum?

I did test all my rockets, they all fling over because of that. But, more important, you were right; putting sep's anywhere else than on the CM solves the problem (I was stuck on my retro-landing thing). It is definitely a bug.

Thank you guys.