Allegheny F-27J
There's no way I know of to positively ID this aircraft, but it's safe to say that it's one of the ten Fairchild F-27 Js Allegheny was flying during early 1966.  The company dubbed their F-27s VISTALINERS thanks to the high wing and very large, elipical windows that surely gave all the passengers imposing views; even those in aisle seats should have been able to see out well.  Harder to understand is why the Convair 580s, with their low wings, huge nacelles and conventional-sized windows, were named VISTACRUISERS.

The F27 was a designed and originally built by Fokker in the Netherlands, and later built under license by Fairchild for the North American market.  I caught this one during a brief period of inactivity between flying its busy schedules; looking at an AL timetable of the day for clues as to what flight it may have been came up empty because there were so many F27 trips shuttling in and out of Philadelphia that there's no way to even guess at it.

Philadelphia, February, 1966