Baltimore and Ohio P-7

The P7s were rather simple locomotives when built. Bearing a considerable resemblance to the Pennsylvania Railroad’s K4s, the two designs did differ in their style of firebox and boiler pressure. The engines produced an impressive 50,000 lbs. of starting tractive effort and could pull heavyweight passenger trains up to 80 miles an hour.[1] Water scoops mounted on the underside of the tender allowed the locomotives to refill their 11,000-gallon tanks without stopping. The cabs of the locomotives were equipped with automatic train control, which improved safety by forcibly applying the brakes if the engineer failed to acknowledge an unfavorable signal.[2]

The engines would receive upgrades over their 31-year careers and some locomotives received streamlined shrouds, but the class never saw a major rebuild . In 1937 locomotive 5304 was rebuilt by the B&O into a Class P-7a streamlined locomotive. In 1942 locomotive 5306 was rebuilt into a Class P-7b streamlined locomotive . In 1944 locomotives 5305,5308,5309,5318 were rebuilt into Class P-7c . In 1946 locomotives 5301-5303 were rebuilt into Class P-7d’s . Locomotive 5304 was also rebuilt to Class P-7d in 1946 .[1]

*The entries in this column are the numbers assigned to the locomotives when built. Some engines were renumbered before being retired.

With the introduction of the P-7 class into its passenger fleet, the B&O sought to distinguish itself from its competitors, mainly the Pennsylvania Railroad. To accomplish this, instead of the usual simplistic black paint scheme, each of the P-7s would be adorned with names after the first 20 Presidents of the United States (a single locomotive, “President Adams”, symbolized both John Adams and John Quincy Adams).  Combined with a vibrant green paint scheme and gold trim, the railroad hoped to make the class more distinctive and memorable. The locomotives were put on display frequently for public relations, with the class making its debut performance at the Fair of the Iron Horse, which celebrated the railroad’s 100^th anniversary in 1927.[2]

The locomotives were used throughout the B&O’s network in the eastern US, with their most famous efforts being the Royal Blue, a high-speed train connecting Washington DC and Jersey City. Also used between Baltimore and Philadelphia, the engines were used mainly in the Midwest leading up to their retirement.[1]

Being an early adopter of diesel power, the B&O retired the P7s by the late 1950s. In 1957, the President of the B&O Howard Simpson ordered the first P-7 built, No. 5300, to be saved from scrapping. The locomotive received a cosmetic restoration to its as-built appearance. Currently on static display at the Baltimore and Ohio Railroad Museum, it is the only pacific type locomotive built for the B&O to have been preserved.[2]

The Class P7 also made appearances in Thomas & Friends as the engine Caitlin is based on the streamlined P7 .