Few Connected Grids Uncontrollable Rotation During Flight

Steps to Reproduce:

1. Build two fully functional ships (each with its own thrusters, gyroscopes, and power).
2. Connect the two ships using any standard connection method (connector, landing gear, or merge block).
3. Activate inertial dampeners and attempt to fly forward or apply any directional thrust (either from one ship’s thrusters or both).
4. Observe the movement.

Expected Behavior:

The connected ships should behave as a single combined rigid body and fly straight in the direction of applied thrust, with no unintended rotation.

Actual Behavior:

The assembly immediately begins to spin/wist around an off-center point. It feels as if the center of mass or force application point is miscalculated, causing thrust to generate a massive torque rather than linear movement. The ships cannot be controlled and rotate endlessly.

Additional Notes:

• The problem reproduces even when only one ship’s thrusters and gyroscopes are active, while the second grid is completely powered off (no thrust, no gyros, all systems shut down). The uncontrollable rotation still occurs, indicating that the issue is not caused by conflicting thruster inputs from both grids, but by the physical connection itself
  Maybe it's FAD or I don't know how configure grids but it looks like issue.