David Kravette, a managing director of Cantor Fitzgerald, the bond trading firm that occupied the upper floors of the North Tower and lost about 700 people, or more than two thirds of its 1,000 U.S.-based employees addressed what he saw in the lobby as the first plane hit. I have provided this quote from the Mercury News New York Bureau since it is the only reference I have seen to the free falling elevators an the fire ball at the lower levels of the tower.
"For Kravette, a 40-year-old father of two, it was his pregnant secretary and a visitor without identification.

 Instead of sending his secretary, Kravette caught an elevator down from the 105th floor to meet clients in the lobby.

``I was trying to be the nice guy,'' Kravette said.

 He emerged in the lobby, slightly aggravated at the inconvenience.

``Which one of you knuckleheads came without an ID?'' Kravette recalled asking, just as a tremendous explosion shook the six-story lobby.

``I saw a couple of elevators in free fall; you could hear them whizzing down and as they crashed, there was this huge explosion, like a fireball exploding out of the bank of elevators,'' Kravette said. ``People were engulfed in flames.''

He escaped across an overpass to the West Side Highway. Three Cantor employees in the lobby suffered severe burns but will survive. His pregnant secretary is missing.