In this Dec. 16, 1960 file photo, residents of the Brooklyn neighborhood of Park Slope stand on brownstone stoops to observe the scene where a United airliner hit Seventh Avenue after colliding with a TWA propeller plane one mile above New York City. Fifty years ago it was the deadliest air disaster up to that time, resulting in the deaths of all 128 people on both aircraft, and six on the ground. (AP Photo/File)