There were no crash physics evident at any of the three sites where planes are supposed to have struck AND PENETRATED buildings.
For the plane for instance to have penetrated the tower, you must assume that it remained intact going through the outerwall.
It is obvious to everyone that whatever, the planes did not smash to pieces and fall into the street.
I will deal with this first.
PHYSICS.
REACTION/deflection
"For every action, there is an equal and opposite reaction".
That means that the force recieved by both objects in a collision will be equal.
Now what determines how much force goes into the objects?Well, if one of the objects penetrates the other, the force needed to break through the penetrated object will be the amount of force recieved by EACH object.
If you add up the total sum of the forces required to "punch" through all of the beams we are told that the plane went through, then you would have to say that the plane sustained that amount of force and did not break up.
I contend that the plane would break up with much less force than what it would take to penetrate all those outerwall beams.
Then there is
TERMINAL BALLISTICS.