A structural problem, or losing control is what redundancy and training exist to prevent. Critical systems carry independent backups, and pilots train specifically for engine-out and control emergencies in a full-motion simulator.
Turbulence is uncomfortable, not a threat to the aircraft — wings are built to flex far past the strongest turbulence ever recorded, and it has never brought down a modern jet.
That rumble or whine is normal — flaps, landing gear, engines changing power. Your pilots hear it every flight and are not reacting to it.
Your luck is not the variable. Every boarding carries the same measured risk, worldwide: about 99.999993% land safely. It does not run low the more you fly, and it is not worse for you than for the person next to you.
