The Southern Railway Ps4 class of steam locomotives have often been called one of the most beautiful designs ever constructed. Likewise, the locomotives adorned in the Southern’s green, white and gold trim that matched the passenger cars they were designated to haul made the Ps4 truly stunning. Thankfully, for history’s sake and that of the railfan community, the Southern Railway recognized the significance of its Ps4s and donated one (which was completely cosmetically restored by the railroad upon delivery) to the Smithsonian Institution in 1961 where it continues to be displayed to this day.
The Southern Railway Ps4 was originally constructed by the American Locomotive Company (Alco) in the early 1920s with an updated version arriving to the railroad later that decade. Like the Baltimore & Ohio’s magnificent EM-1 locomotive class the Ps4s did not have a considerably long lifespan for a steam locomotive. After Alco delivered the last Ps4s in the late 1920s they survived less than thirty years before being retired in 1952 and replaced by the Electro-Motive Division’s (EMD) E7 diesel-electric locomotive to pull the Southern’s premier passenger trains.
The Southern Railway Ps4, being built for passenger service, also did an excellent job in what was required of them. With their larger driving wheels they were capable of speeds approaching 80 mph with nearly 1000 tons in tow and regularly cruised the Southern’s Washington to Atlanta main line at nearly 60 mph.
The Southern Railway Ps-4 Class Specifications
Wheel Arrangement - 4-6-2
Builder - American Locomotive Company (Alco)
Original Year of Construction - 1926
Cylinders(2) - 27" x 28"
Boiler Pressure - 200 PSI
Driver Diameter - 73 Inches
Tractive Effort - 47,535 Pounds
Weight on Drivers - 182,000 Pounds
Locomotive Weight - 304,000 Pounds
Perhaps what most set apart the Ps4 was the very livery applied to them by when almost every other steam locomotive in the country carried all black, sometimes including white trim here and there. They were indeed beautiful, there is no denying that, and they were an exclusive few to receive the paint scheme (even among the Southern locomotive fleet) as the railroad only applied it to those locomotives who would be leading the railroad’s regal passenger trains (such as the Southern’s flagship, the Crescent Limited).
For more information on the Southern Railway Ps4 Pacifics consider one (or both) of the books below. Guide to North American Steam Locomotives by author George Drury includes nearly 500 pages of information on virtually all of the steam locomotive wheel arrangements and designs (including streamlined steamers) ever developed. The book is a great resource on steam locomotives and a fine reference tool; you should find it very useful.
Also, consider the book American Steam Locomotives from author Brian Solomon. While this publication does not include quite as much technical data as Guide to North American Steam Locomotives it is still a very good resource with lots of information and best of all, is loaded with photographs!
