The A4s were a class of 0-4-0 switcher steam locomotives built by Altoona Works for the Pennsylvania Railroad from 1906 to 1913. They had a Belpaire firebox and 50" drivers.

Class A was the 0-4-0 type, an arrangement best suited to small switcher locomotives (known as "shifters" in PRR parlance). Most railroads abandoned the 0-4-0 after the 1920s, but the PRR kept it for use on small industrial branches, especially those with street trackage and tight turns.

The Pennsylvania Railroad 's class A5s was the most powerful class of 0-4-0 steam locomotives. The Pennsylvania Railroad built 47 in its Juniata Shops between 1916–1924. They were all retired by 1957. One is preserved at the Railroad Museum of Pennsylvania.

Feb 16, 2003 · Like most PRR designs, these burned fuel in Belpaire fireboxes that were scarcely visible in the large cabs. Virtually all were converted to A-3a saddle tank engines, which saw the removal of the double-bogie slopeback tender. The work led to a weight increase to 98,600 lb (43,363 kg). about 8 short tons higher.

Class A was the 0-4-0 type, an arrangement best suited to small switcher locomotives. Most railroads abandoned the 0-4-0 after the 1920s, but the PRR kept it for use on small industrial branches, especially those with street trackage and tight turns. Class B comprised the 0-6-0 type, the most popular arrangement for switcher locomotives on the PRR.

This page includes instructions for obtaining Copies OF PRR (Pennsylvania Railroad Company) Mechanical Engineering Drawings for a Particular Locomotive or Piece of Rolling Stock.

Oct 1, 2023 · PRR #129 - A4 Class We can definitely confirm the use of at least one A class 0-4-0 with slope-back tender, however the locomotive number is obscured, but the print is labeled #13; March 3, 1929.

The 4-6-4 arrangement was seen on the PRR only on electric locomotives. As a steam locomotive arrangement, it was poorly suited to the PRR's mountainous terrain, wasting much potential adhesive weight on non-driven wheels.

With Sir Nigel just finishing its overhaul, and Bittern in the queue, there are already functional A4s around to see. It would take so much work to fix up Mallard that it’s better to just let her be a …

Class A was the 0-4-0 type, an arrangement best suited to small switchers. Most railroads abandoned the 0-4-0 after the 1920s, but the PRR kept it for use on small industrial branches, especially those with street trackage and tight turns. Class B comprised the 0-6-0 type, the most popular arrangement for switchers on the PRR.