At the Pentagon there was a fortified concrete wall. Do you have any indication that the same applied to the twin towers? Are you saying the windows were actually protected by invisible fortified concrete ❓
Thats is the problem with all explanations trying to prove the offcial version. They pose more questions than they answer.
For the WTC the outer steel mess structure was also part of the building support structure. It was designed with a central "spine" of colums with the steel meshing acting like a exoskeleton. Thui enabling unintrupted floor space without support beams jutting in.
Agreed the pentagon walls were made of reinforced steel, But the windows wern't. The windows on top and to the sides of the so called impact hole are still intact, one would think getting hit at 500mph would at the very least crack even the sturdiest blast proof windows ( This is just as assumption, hoping the pentagon would have those kind of security measures )
If the fuselage, which is basicaly a empty aluminum skinned tube penetrated and damaged 3 feet of reinforced concrete ( the outer and wall of the other pentagon ring each 1.5 foot thick ). The engines which are mostly make of titanium one of the strogest metals on earth would atleast penetrate or even severly damage the outher wall. And these are the best case scenarios trying to fit into the official version.
Again you can't have it both ways. Its either this or that.