Does anyone know what is happening? When my SSTO takes flight from the runway, after a few seconds it violently veers off to the left or right-hand side, which side is seemingly at random. I double-checked everything I could, (Center of mass/flight/thrust, symmetry of the spaceplane etc) and I can't seem to find an answer to why this is happening. Any help would be appreciated greatly, as this is such an annoying thing that keeps happening to all my larger planes.
If I need to send a video or something more then just tell me.
The only mods I have installed are KAX, Kerbal Atomics, and Stockalike Station Parts Expansion by Nertea_01.
My game version is: 1.12.5.