The whole plane? I recall the very tail end wedged in the hole yes but are you saying the entire plane was completely intact?
It wasn't, try again.
It penetrated the building, parts of it emerged out the other side.
It did not splat against the facade like a fly.
It was also much smaller and traveling around half the speed of the planes that hit the WTC. The structural design of the ESB should also be considered. A conventional steel frame and masonry design. The WTC had open space beyond the facade, nothing more to stop the momentum of the shredding aircraft. Until the core columns that is, and many of those were destroyed or damaged.
This is basic stuff even I can understand! I don't even have a PhD and I get it! Why can't you?