There's a post by Tadman in the SEPTA forum showing a (rare) photo of a train of MP54's on the High Line en route to Greenwich Yard for the Army-Navy Game, and it started me wondering whether all the Army-Navy specials needed a pilot; I can't imagine there were many passenger enginemen qualified on the High Line and the Delaware Extension. In view of the signaling changes effective on the Delaware Extension on that day only I wonder whether some additional qualification would be required even if they were qualified. I think it was a unique situation in American railroading: a double-track railroad with Rule 251 in the same direction on both tracks in the morning and in the opposite direction in the afternoon. The C&S department worked feverishly to flip the signals on one track before the game, on both tracks during the game, and then on the other track after the game to put everything back the way they found it. (Later on they installed Rule 261 on both tracks permanently.) Did the PRR have to ferry pilots by taxi to North Philadelphia and Brill?
The runs may have been filled from the Extra Board, and the engineers, especially, may not have been restricted to passenger or freight. I remember in PennCentral days riding a Chestnut Hill Local and the young engineer mentioning that he usually ran freight trains as an extra man, as men with seniority usually got most passenger runs. I'll ask on the PRRFax Yahoo Group.
https://groups.yahoo.com/neo/groups/PRR