One interesting aspect of this theory, is the fact that if you look at the slow motion clip of the final moments into the building, you notice how this plane flows through the outside wall of the building w/o causing any damage neither to itself, nor to the outside wall of steel & concrete of the building. It literally looks like if the image was just moving through. The plane did not squash itself like an accordion, the wings never lost their original angles, & nothing flew away from neither the plane nor the building.
Aircraft are made of lightweight aircraft aluminium.
Aircraft are hollow and extremely lightweight as they are designed to fly through the air.
Though strong in the 'lateral' plane...'bending'...the airframe will simply disintergrate on impact with ANYTHING solid.
The densest part of the aircraft is it's engines.
There was little or no debris ejected 'backwards' because of the initial momentum of the object--->upwards of 400mph. Bits and peices do not simply reverse direction in an instant and go back the other way. They will deflect to a degree but carry on in the same direction. Or else TOTALLY disintergrate.
The WTC was solid...as a rock.
For this same reason...the nice neat holes punched through the Pentagon and the report of the 'intact' nose cone show an obvious missile strike. The nose cone is the DU penetrator warhead. Note the initial explosion...it is a mix of white hot with the dull red of burning jet fuel from the ALCM...the "white hot" is the ignition of the high explosive warhead.