It was the accident pilots and passengers in the still-new jet age had feared the most — a distinctly new kind of catastrophe, one that had never happened over a major urban area, one that would have seemed far less terrifying a few years earlier, when planes were smaller and slower.

Two airliners feeling their way through a sloppy mess of fog and sleet collided over New York City, sending down a devastating shower of flaming wreckage.

On a street of brownstones in Park Slope, Brooklyn — a run-down neighborhood at the time politely described as being “in transition” — one plane, a state-of-the-art jetliner, gouged long-lasting scars. The tail slammed down in an intersection. White-hot engines, smoldering cargo and badly burned bodies fell nearby. A stream of jet fuel touched off a fire that grew to seven alarms and destroyed at least 10 buildings, including a church. Two men selling Christmas trees on a corner and a man shoveling snow were killed....