My DD works for the Hudson River Park Trust. They have a classroom on the pier right next to the Intrepid. (That's where we met her recently for lunch.) She wasn't at that site when this happened but at the main office which is on the waterfront 4 blocks further up.
They heard the sirens but didn't give them much attention at first. They thought they were the usual drills that they always conduct.
Believe me, this gave me a big case of the "what ifs?" She was definitely in harms way had that plane not landed the way it did.
It's definitely a miracle. Coincidentally, my other DD was here from Charlotte last week. (They drove, but she has been on that flight out of La Guardia.)
It really is amazing.