Originally Posted by
rickair7777
...As someone mentioned: centrifugal force. ...
For the sake of Saturday speculation, I do not think centrifugal force is the issue with a large airliner in a spin. It is the flight control surfaces that would buckle in the recovery, probably the outer wing. You are going to get a turn rate in an airplane of this size in the neighborhood of 15-30 RPM in a fully developed spin. Forces on the wing and tail in the recovery would be the main issue. I think it could be done even though the airplane would be toast- that much is certain because the positive g's on recovery is what breaks things. The spin itself is easy on an airframe.