Chesapeake & Ohio 4-6-4 "Hudson" Locomotives in the USA

Class L-1 (Locobase 9382)

Data from C&O 12 - 1946 diagram books supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also Philip Shuster, Eugene Huddleston, and Alvin Staufer; C&O Power (Alvin Staufer, 1965), p. 255.

As Pacifics, the F-19s (Locobase 137) were regarded as one of the best designs of that wheel arrangement in service. At the close of World War II, however, the Chessie decided to upgrade their passenger service with a premium express connecting Washington & Cincinnati called the Chessie.

Although characterized as a rebuild, in fact the railroad's makeover retained only the firebox from the 20-year-old engines. Karen Parker, "The C & O's Homemade Hudsons", Chesapeake and Ohio Historical Magazine (May 2006) provides a summary of the extensive rework undertaken by the Huntington shops:

*A new, one-piece cast frame with integral cylinders and main air reservoir.

*Roller bearings on all axles and in the main and side rods.

*Multiple-bearing crossheads, replacing the alligator type used on the F-19.

*New drivers that were carefully cross-counter-balanced to enable high-speed operation.

*An entirely new structure inside the boiler, reusing only the outer shell, with 41 tubes of 2.25'' outside diameter (171 fewer) and 195 flues of 3.5'' O.D. (147 more).

*A renewed but otherwise unchanged firebox.

*A Type E superheater, replacing the Type A of the F-19, and providing significantly increased super-heater heating surface (2001 sq. ft., a 65% increase) and 250 of superheat rather than 150 in the Type A.

*Slightly higher boiler pressure (210 psi vs. 200 psi).

*Cylinders of the same size (27'' x 28'') but now equipped with Franklin Type A poppet valves (oscillating cam type).

*A four-wheel trailing truck with a Franklin type E-I high speed booster, capable of operation up to 35 mph.

*A more efficient Worthington feedwater heater taken from an F-17 Pacific, which got the Elesco feedwater heater from the F-19.

*A new, very large cab."

The result was a considerably heavier engine that shone in stainless steel and a bright red-orange sloped nose and upper casing.

Parker comments that the rebuild did not have a combustion chamber and speculates that the boiler's length may have precluded its retention. Moreover, the poppet valves provided a healthy increase in horsepower. She quotes Gene Huddleston's anecdote of the engineer whose L-1 ran so smoothly and effortlessly one day that it was only the dynamic augment of a locomotive that was exceeding its counterbalanciing speed that awoke him to the realization that he was hitting 95 mph (153 kph) with six heavyweight cars.

Although the Chessie never actually ran, the L-1s put in good service throughout the C & O's passenger network. Their 74" drivers offered little real hindrance to very fast running because of the roller bearings distributed throughout. In April 1953, the first two were retired with the other three being replaced by diesels by mid-1955.

Class L-2 (Locobase 179)

Data from individual builder's cards preserved at SMU's DeGolyer Library at [], last accessed 30 August 2016; and C&O 12 -1946 Locomotive Diagrams supplied in May 2005 by Alen Stanley from his extensive collection. See also Philip Shuster, Eugene Huddleston, and Alvin Staufer; C&O Power (Alvin Staufer, 1965), p. 234. (Thanks to Chris Hohl for his 8 August 2016 email reporting the differences in booster tractive effort between the two L-2 subclasses and providing the above-cited links; and for his 22 September 2017 email reporting unlikely boiler pressure values for 177 entries. A Locobase macro caused the error.) Works numbers were 64351-64358 in December 1941-January 1942.

Firebox heating surface included 96 sq ft (8.92 sq m) in two thermic syphons, 81 sq ft (7.53sq m) in the combustion chamber, and 19 sq ft (1.77 sq m) in arch tubes. Roller bearings on all axles and, on the roller bearings on the main and side rods. An Elesco Type E feed water heater preheated the boiler water and 14" (356 mm) piston valves supplied steam to the cylinders. The Franklin Type E 12,600 lb (5,715 kg) booster was a "high-speed passenger" type that could remain engaged up to 33 mph (53 kph). The L-2 was rated to pull a fifteen-car train at 90 mph (145 kph) on tangent level track.

Five later engines--L-2a, which were the last passenger steam locomotives ordered in the US--are show in Locobase 16231.

Class L-2a (Locobase 16231)

Data from individual builder's card Baldwin Negative No 14,639 preserved at SMU's DeGolyer Library at [], last accessed 30 August 2016; and C&O 4 -1947 Locomotive Diagrams supplied in August 2013 by Allen Stanley from his extensive collection. See also Philip Shuster, Eugene Huddleston, and Alvin Staufer; C&O Power (Alvin Staufer, 1965), p. 234. (Thanks to Chris Hohl for his 8 August 2016 email reporting the differences in booster tractive effort between the two L-2 subclasses and providing the above-cited links. Thanks also to Jackie Lien for 10 April 2017 email questioning the tender weight, which prompted a correction; and his 30 July 2017 noting the correct engine weight.) Works numbers were 73533-73537 in August 1948.

It's difficult to find an objectively based reason for a major US railroad ordering five more expensive steam locomotives in 1948. But the C&O was a coal road and believed that up-to-date steam design could compete with diesels. So it reworked the 1942 L-2 (Locobase 179) and bought the last five steam-powered express passenger locomotives produced in North America.

The boiler retained the same tube and flue counts and lengths, but the thermic syphons installed in the earlier engines were replaced by four security circulators that contributed 60 sq ft (5.57 sq m) to the heating surface area. 19 sq ft (1.77 sq m) of arch tubes were also eliminated. Late-steam era components included a 14,200 lb (6,441 kg) booster, feed water heater, mechanical stoker, one-piece cast steel bed with integral cylinders, and air brake on all engine and tender wheels. Roller bearings reduced friction on every axle: 13" (330 mm) diameter roller bearings on the main driver, 12 1/2" (318 mm) on the other coupled axles, 8 1/4" (210 mm) on engine truck wheels, and 7" (178 mm) rollers on the tender truck axles.

Another substantial change replaced standard piston valves with Franklin rotary poppet valves, which had proven their worth in the L-1 conversions (Locobase 9382).