Pennsylvania Railroad EMD SW 1 yard switcher locomotive.

Pennsylvania Railroad EMD SW 1 yard switcher locomotive., a photo by Eddie from Chicago on Flickr.

I found this photo at My Link page Fallen Flags.Org, located to the right of Your computer screen.

The former Pennsylvania Railroad, was one of many North American railroads, that owned a large fleet of diesel switching locomotives during the late steam and early diesel transition era back in the 1940's and 50's.

The model shown here, is an EMD model SW 1 yard switcher, wich was introduced in 1939.
This was a popular and economical yard switching locomotive at the time.

As freight and passenger trains eventually became longer and heavier, these locomotives eventually became inadequate for the job, and were primarilly assigned to branchline switching locals, or even shop switchers.

Many of these locomotives would find homes operating for shortline railroads. Some would prove themselves ideal for industrial applications, like in plant switching locomotives at places like stone quarries, steel mills or even oil refineries.

The EMD SW 1 was a well built machine, and many would be found in recent times hauling tourist trains on excursion railroads like the Wilmington & Western in the state of Delaware. The Illinois Railway Museum in nion Illinois, operates a former Commonwealth Edison Company in plant EMD SW 1 switcher, and the Western Pacific Railroad Museum in Portola Californa....owns the former Western Pacific Railroad's first diesel locomotive, wich is an EMD SW 1 from 1939.

During the 1980's Amtrak used a few EMD SW 1's to switch Chicago Union Station. In nearby west suburban Cicero Illinois, the Manufacturers Junction Railway used two of these to switch on line industries in to recent times.