At some point in the years just after World War II the Pennsyvania Railraod operated an integrated light weight diesel powered passenger train on a test schedule from Philadelphia to Pittsburgh and back the same day. Jerry Schickler informs me that it was built by General Motors and called the "Aerotrain". It left Philadelphia at 8 am and arrived at Pittsburgh at 1pm. Five hours for this run sounds pretty fast. I can't recall what the timing of the Broadway Limited was between these two cities when it was scheduled to run from New York to Chicago in 16 hours (the New York Central Twentieth Century Limited had the same schedule on its slightly longer "water level route").
We all know what has happened to American rail passenger service since then
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