Flipping rocket

[MaximilianPs]

Can some one explain why, a rocket that was working fine just tonight, now flip like hands of an analog clock ?

http://imgur.com/a/g0yNB

It's driven by an OCTO, but at 10.000 meters start flipping as hell without no reason and there's no way to stop it.

when the Kickback propellant reach 50% it start flipping, but early it was just fine, I've used this thing to take in orbit a bunch of strange and asymmetrical object, so I really can't get why it do this behavior now.

Edited June 16, 2016 by MaximilianPs

[T-Bouw]

Can you give us a pic of the state of the vehicle when it reaches 10Km?
I'm guessing it has shed some stage(s) at that point in the flight.

Though from what I can tell already, I see a lot of draggy parts at the top (solar panels, etc) and only a few tailfins at the bottom that probably get discarded.
Balance of draggy bits is key.

[MaximilianPs]

I've made two more test and at the same height... about 7k become uncontrollable.
http://imgur.com/a/CkKdF

Looks like that I've been able to fix it by dismounting all structs and then reinstalling 'em 

This is pretty irritating, btw, I'm open to every advice on this kind of problem 'cause I would like to take in orbit some weird hardware, so Tips are always welcome  

 

Look how far it goes without pushing a single key 
http://imgur.com/27jH1MS

Edited June 16, 2016 by MaximilianPs

[kBob]

What happens if you put delta-deluxe wings on the bottom of all your stacks (including the boosters)?  If I'm having trouble with a large asparagus setup I find the ddw will often help though depending on balance it can be hard to turn; often I'll wait until I've dropped all the solid boosters before I try turning.  Or maybe redesign a little and add a fuel tank and engine stage to that center piece but stage it so it won't start until you are up a ways (past the trouble point).

[MaximilianPs]

For some reason it wasn't symmetric anymore, I've checked each single peaces and I notice that the X on the top was shifted by side.

Still wonder why, but a bug, maybe mine fault ? 

 

Anyway problem Fixed, thanks everybody for the support  

[ineon]

This is also useful.

tl;dr: CoM shifts in flight, add more fins at the back or more mass at the front.