Amtrak SW-1 #732, Chicago, IL, June 7, 1982, photo by Chuck Zeiler

Amtrak SW-1 #732, Chicago, IL, June 7, 1982, photo by Chuck Zeiler

On a hazy Chicago day, Amtrak SW-1 #732 is about to wye a train through the Union Avenue interlocking. I cannot determine the origin of #732. I have photos of the same locomotive painted solid black dated 1979, so I assume this was formerly a Penn-Central SW-1.

In the background is BN NW-2 #543, delivered to the CB&Q in August 1946 as #9246 (c/n 3642), awaiting its turn through the interlocking.

Overhead is a C&NW transfer on the St. Charles Air Line. This was the Illinois Central's (by this date, the ICG) westward main line through Illinois and Iowa. The name "Air Line" denotes that the rails ran as straight as possible, as if a line was drawn in the air, avoiding as many curves as was possible. The caboose (#12557) was a wide vision, but has acquired steel plating over the cupola windows, likely in conformance to FRA glazing regulations.