Baltimore and Ohio P-7

The Baltimore and Ohio’s P-7 class was a class of 20 Pacific type locomotives built in 1927. Named for the first 20 Presidents of the United States, they were the prime motive power for the B&O’s top passenger trains for 31 years. One example, No. 5300, “President Washington”, has been preserved.

Baltimore and Ohio P-7
Type and origin Power type Steam Builder Baldwin Locomotive Works Serial number 59881–59886, 59928–59937, 59973–59976 Build date 1927 Total produced 20
Specifications Configuration: ​  • Whyte 4-6-2  • UIC 2′C1′ h2 Gauge 4 ft 8 ^1⁄2 in (1,435 mm) Driver dia. 80 in (2,032 mm) Adhesive weight 201,000 lb (91,000 kg; 91 t) Loco weight 326,000 lb (148,000 kg; 148 t) Total weight 544,000 lb (247,000 kg; 247 t) Fuel type Coal Water cap 11,000 US gal (42,000 l; 9,200 imp gal) Firebox:  • Firegrate area 70.3 sq ft (6.53 m^2) Boiler pressure 230 psi (1.6 MPa) Cylinders 2 Cylinder size 27 in × 28 in (686 mm × 711 mm)
Performance figures Maximum speed 85 mph (137 km/h) Tractive effort 49,882 lbf (221.89 kN) Factor of adh. 4.03
Career Retired 1958 (last) Disposition One example, No. 5300, preserved.

Design

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]

B&O Pacifics[1]

Class	Quantity	Road Numbers*	Build Year	Builder
P	35	2100-2134	1906	ALCO
P-1	10	2135-2144	1911	Baldwin
P-1a	30	2145-2175	1911	Baldwin
P-1c	30	5000-5009, 5035-5049, 5090-5094	1924	B&O
P-3	30	5100-5129	1913	Baldwin
P-4	10	5130-5139	1917	Baldwin
P-5	30	5200-5229	1919	Baldwin, ALCO
P-6	15	5230-5244	1923	Baldwin
P-7	20	5300-5319	1927	Baldwin
P-9	1	5320	1928	B&O

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

Service

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]

Preservation

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]

In Fiction

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

1. "Baltimore & Ohio / Buffalo, Rochester, & Pittsburgh / Cincinnati, Hamilton & Dayton / Cincinnati, Indianapolis, & Western 4-6-2 "Pacific" Locomotives in the USA". 2019-04-08. Archived from the original on 2019-04-08. Retrieved 2020-04-10.
2. "B&O; No.5300". 2019-04-15. Archived from the original on 2019-04-15. Retrieved 2020-04-10.