Chesapeake & Ohio 4-6-2 "Pacific" Type Locomotives

Introduction

The Chesapeake and Ohio was among the first railroads to test the 4-6-2 wheel arangement (around 1902) and had at least one 4-6-2 before the Missouri Pacific (from which the wheel arrangement gots its name). The C&O originaly called the 4-6-2s "Mountains", but the name did not stick. Their official name on the C&O was "Ten Wheeler with trailer".

The F-19 class of C&O Pacifics were the only Pacifics to be delivered new with Elesco feedwater heaters, flying (smokebox-mounted) airpumps, and deck-mounted headlights. They all were equiped with vanderbuilt tenders which carried the large C&O logo on the coal bunker sides.

These locomotives became the standard power for the George Washington (a night sleeper train) on most of the route between Washington and Newport News to Chicago. The F-19 class was considered to be the manifestation of the Georgian steam locomotive and was generally believd to be the prettiest locomotives the C&O ever owned.

In 1946 and 1947 they were rebuilt into streamlined class L-1 4-6-4 Hudsons (the road numbers remained the same). One, number 490 still survives at the B&O Railroad Museum.

Roster by Richard Duley

ClassQty.Road NumbersYear BuiltBuilder
F-195490 - 4941925 - 1926 

Class Details by Steve Llanso

Class F-15 - 1902 (Locobase 136)

Data from table in AERJ July 1903. Firebox heating surface included 23 sq ft of arch tubes.

First of a prolific line. These had no superheaters, Stephenson link motion, and a classic late 19th-Century profile. Among the first "Pacifics" to be built in the US. See Locobase

7605 for the as-delivered superheated version.

According to the C&O 9-1936 diagram books supplied in May 2005 by Allen Stanley from his extensive collection, those saturated engines that were superheated varied in the number of tubes and flues installed . 430's boiler held 149 2 1/4" tubes and 26 5 1/2" flues while 431 had 168 tubes and 30 flues. Almost all of the rest had 166 2 1/4" tubes and 30 5 1/2" flues. New-built F-15s with superheaters installed had 183 2" tubes.

Class F-15 - 1906 (Locobase 11441)

Data from table in AERJ July 1903. Firebox heating surface included 23 sq ft of arch tubes.

First of a prolific line. These had no superheaters, Stephenson link motion, and a classic late 19th-Century profile. Among the first "Pacifics" to be built in the US. See Locobase

7605 for the as-delivered superheated version.

According to the C&O 9-1936 diagram books supplied in May 2005 by Allen Stanley from his extensive collection, those saturated engines that were superheated varied in the number of tubes and flues installed . 430's boiler held 149 2 1/4" tubes and 26 5 1/2" flues while 431 had 168 tubes and 30 flues. Almost all of the rest had 166 2 1/4" tubes and 30 5 1/2" flues. New-built F-15s with superheaters installed had 183 2" tubes.

Class F-15 - 1911 (Locobase 7605)

Data from reproduction of 1913 Alco Bulletin 1016 on Richard Leonard's http://www.railarchive.net/alcopacifics/index.html (accessed 16 June 2006).

In Locobase 136, one of the earliest examples of this long line of C & O Pacifics appears in its saturated version. By the end of the run in 1911, Richmond was delivering the class with superheaters installed. An observer can note the tradeoffs between evaporative heating surface and superheater area. The builder took the unusual approach of reducing the diameter of the individual small tubes from 2 1/4" to 2", but adding 5 1/2" flues instead of the more usual (for the time) 5 3/8". As usual in that period, superheating meant a reduction of boiler pressure, too.

It was a design modification that changed little else. Inside Stephenson link motion still actuated the valves, the firebox heating surface retained its 23 sq ft of arch tubes, and the grate area remained unaltered as well.

F-15s were later (1915-1924) rebuilt with superheaters, mechanical stokers, Walschaerts valve gear, new cylinders, and sometimes new frames. Saw steam out on the Chessie.

Class F-16 (Locobase 6489)

Data from Eugene L Huddleston's article in the January 1999 Chesapeake and Ohio Historical Review. See also DeGolyer, Vol 47, p.33. Works numbers were 40070-40073 in June 1913; 40154-40157 in July.

Huddleston says that although these were Baldwin products, they duplicated Alco's #50,000 (see Locobase 128) in grate area, firebox size, heating surface, bore and stroke, and adhesion weight. (Locobase finds that data from C&O Locomotive Diagram book from 1936 (supplied by Allen Stanley in May 2005) shows some differences from the Alco design.) 16" diameter piston valves served the cylinders. Firebox heating surface included 30.8 sq ft (2.86 sq m) of arch tubes. As a concession to the C&O's hilly profile, driver diameter was decreased by 5".

Baldwin's specs reveal that the C&O expected the F-16s to pull a 692 ton train consisting of:

1 steel express and 1 steel postal car, each weighing 113,200 lb (51,347 kg)

1 steel combined car of 130,300 lb (59,103 kg)

1 steel coach of 135,200 lb (61,326 kg)

1 diner of 157,700 lb (71,532 kg)

5 steel sleepers weighing 147,000 lb (66,678 kg).

The ruling grade over which the trains were to keep time was 60 ft/mile (1.1%) over a 13 1/2 mile (21.7 km) stretch from milepost 291 to Allegheny, Va. Up this stretch, the trains were to average 24 mph (38.6 km/h). According to Huddleston, "From their construction in 1913 to their scrappings in 1951-1952, the F-16s served well." At first they hauled flatland expresses trains, later taking the Charlottesville-Newport News and Ashland-Louisville sections. Over the years, the locomotives were fitted with automatic stokers.

After World War II, the class entered what Huddleston describes as heavy-duty local service such as the daily Ashland-Elkhorn run and the Columbus-Toledo "accommodation train."

Class F-17 (Locobase 3075)

These "Mountain Pacifics," if they can be so described, began their careers operating between Charlottesville, Va and Hinton, WVa over three mountain ranges. Their target was to pull 10-car trains (674 tons) at an average speed of 25 1/2 mph.

In addition to the Schmidt superheater, these engines had a Ragonnet power reverse gear, Locomotive Stoker Company type C, Street mechanical stoker and Franklin pneumatic grate shaker. Firebox heating surface includes 27.4 sq ft of arch tubes.

In the 1930s, their driver diameter was increased to 74". The boiler pressure seems low; all the dimensions -- including 16" piston valves -- suggest a design capable of even more power. See Locobase 9104.

Class F-17A (Locobase 9104)

Data from the C&O 9-1936 diagram books supplied in May 2005 by Allen Stanley from his extensive collection.

Locobase 3075 describes this Richmond-built sextet as they first saw service rolling on 69" drivers. In the mid-1930s, the C & O rebuilt the engines with 74" drivers to enhance their usefulness on heavy passenger trains. Although the boiler layout remained essentially the same and still had the 4 arch tubes contributing 29 sq ft to firebox heating surface area, boiler pressure increased to 200 psi and the vessel now contained a Worthington feedwater heater; steam was still admitted to the cylinders by large 16" piston valves. Wheelbase grew by almost a foot, adhesion weight by almost 8 tons and engine weight by almost 11 tons. The loaded tender itself, which rolled on 6 axles, weighed 150 tons and would later grow to 347,000l lb as it held 18,000 gallons of water and 28 tons of coal.

Class F-18A (Locobase 7857)

Data from the C&O 9-1936 diagram books supplied in May 2005 by Allen Stanley from his extensive collection.

The F-18 took the final form of the C & O Pacific that's better known as its slightly younger F-19s. In the early 1930s, the class was rebuilt as F-18A.

Class F-19 (Locobase 137)

Data from 1930 Locomotive Cyclopedia table and from C&O 9-1936 and 12 - 1946 diagram books supplied in May 2005 by Allen Stanley from his extensive collection.

Boiler had feedwater heater, piston valves measured 14" in diameter (less than those of the F-17). The omega of C & O Pacifics, they entered service with 12,000-gallon, 15-ton coal tenders, but were later fitted with the enormous vessels shown in the specs. Also, the all in the class were fitted with roller bearings on the engine trucks; most used SKF, 494 rolled on Timkens.


Specifications by Steve Llanso
ClassF-15 - 1902F-15 - 1906F-15 - 1911F-16F-17F-17AF-18AF-19
Locobase ID136 11441 7605 6489 3075 9104 7857 137
RailroadChesapeake & Ohio (C & O)Chesapeake & Ohio (C & O)Chesapeake & Ohio (C & O)Chesapeake & Ohio (C & O)Chesapeake & Ohio (C & O)Chesapeake & Ohio (C & O)Chesapeake & Ohio (C & O)Chesapeake & Ohio (C & O)
Whyte4-6-24-6-24-6-24-6-24-6-24-6-24-6-24-6-2
Road Numbers430-456437-448166-173174-181 / 460-467470-475470-475480-485490-494
GaugeStdStdStdStdStdStdStdStd
BuilderAlco-RichmondAlco-RichmondAlco-RichmondBaldwinAlco-RichmondC & OAlco-RichmondAlco-Richmond
Year19021907191119131914193419231926
Valve GearStephensonStephensonStephensonWalschaertWalschaertWalschaertBakerBaker
Locomotive Length and Weight
Driver Wheelbase12.67'12.67'12.67'13'13'13'13'13'
Engine Wheelbase32.67'32.67'32.67'34.08'34.75'35.42'35.58'36.58'
Ratio of driving wheelbase to overall engine wheebase 0.39 0.39 0.39 0.38 0.37 0.37 0.37 0.36
Overall Wheelbase (engine & tender)60'60'60.71'75.19'71.96'83.42'83.42'76.48'
Axle Loading (Maximum Weight per Axle)67240 lbs67240 lbs66700 lbs
Weight on Drivers131000 lbs158000 lbs163000 lbs190000 lbs191455 lbs199830 lbs199830 lbs200000 lbs
Engine Weight190000 lbs211000 lbs221000 lbs290000 lbs312605 lbs334420 lbs334420 lbs331500 lbs
Tender Light Weight119000 lbs119000 lbs131000 lbs245000 lbs300000 lbs305000 lbs347000 lbs
Total Engine and Tender Weight309000 lbs330000 lbs352000 lbs535000 lbs634420 lbs639420 lbs678500 lbs
Tender Water Capacity6000 gals6000 gals7000 gals12000 gals16000 gals16000 gals18000 gals
Tender Fuel Capacity (oil/coal)9 tons9 tons9 tons15 tons tons20 tons20 tons28 tons
Minimum weight of rail (calculated) on which locomotive could run73 lb/yard88 lb/yard91 lb/yard106 lb/yard106 lb/yard111 lb/yard111 lb/yard111 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter72"72"72"74"69"74"74"74"
Boiler Pressure200 psi200 psi190 psi185 psi185 psi200 psi200 psi200 psi
Cylinders (dia x stroke)22" x 28"22" x 28"23" x 28"27" x 28"27" x 28"27" x 28"27" x 28"27" x 28"
Tractive Effort31998 lbs31998 lbs33224 lbs43376 lbs46519 lbs46892 lbs46892 lbs46892 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.09 4.94 4.91 4.38 4.12 4.26 4.26 4.27
Heating Ability
Firebox Area205 sq. ft203 sq. ft250.80 sq. ft282.80 sq. ft281 sq. ft281 sq. ft281 sq. ft
Grate Area47 sq. ft47.90 sq. ft46.80 sq. ft60.40 sq. ft80.33 sq. ft80.70 sq. ft80.70 sq. ft80.30 sq. ft
Evaporative Heating Surface3533 sq. ft3755 sq. ft2971 sq. ft3782 sq. ft4479 sq. ft4470 sq. ft4239 sq. ft4239 sq. ft
Superheating Surface649 sq. ft879 sq. ft991 sq. ft1070 sq. ft1213 sq. ft1213 sq. ft
Combined Heating Surface3533 sq. ft3755 sq. ft3620 sq. ft4661 sq. ft5470 sq. ft5540 sq. ft5452 sq. ft5452 sq. ft
Evaporative Heating Surface/Cylinder Volume286.79304.81220.65203.83241.39240.91228.46228.46
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation9400958088921117414861161401614016060
Same as above plus superheater percentage94009580104931329717536192071969119593
Same as above but substitute firebox area for grate area410000455135521461735668786856468564
Power L188800166401592116983206122201622016
Power MT448.330675.18554.21586.68682.20728.67728.05

Reference

Credits

Introduction and roster provided by Richard Duley. Class details and specifications provided by Steve Llanso of Sweat House Media.