According to wiki, it happened in the University City section of San Diego aka the Golden Triangle bounded by State 52 (e/w), I5 (n/s), and I805 (n/s). The plane crashed just north of 52 near Cather Ave and Huggins St (west of I805)
I looked it up because a family member lives across from Balboa Park, and I don't know how far away that would be. If you look it up on mapquest, the only way I could get it to work was to enter my relative's address (don't want to give it) then slide the map and zoom in, look northeast from University City for those streets and to the west for I805 which bounds Miramar on one side.
I heard he followed it in as far as he could, attempted to save the plane, punched out at the last moment and was recovered in a tree. It didn’t sound like it was easy on the pilot either, though perhaps in God’s Plan the pilot is remaining alive for another purpose, while those who have been taken are now in a far better place and have been promoted.