Building 7 was not hit by an airplane, it only had superficial damage caused by falling debris from the twin towers.
WTC7 Damage
Captain Chris Boyle
Engine 94 - 18 years
Boyle: ...on the north and east side of 7 it didnÂ’t look like there was any damage at all, but then you looked on the south side of 7 there had to be a hole 20 stories tall in the building, with fire on several floors. Debris was falling down on the building and it didnÂ’t look good.
Firehouse: When you looked at the south side, how close were you to the base of that side?
Boyle: I was standing right next to the building, probably right next to it.
Firehouse: When you had fire on the 20 floors, was it in one window or many?
Boyle: There was a huge gaping hole and it was scattered throughout there. It was a huge hole. I would say it was probably about a third of it, right in the middle of it. And so after Visconti came down and said nobody goes in 7, we said all right, weÂ’ll head back to the command post. We lost touch with him. I never saw him again that day.