New York, Philadelphia & Norfolk / Northern Central / Pennsylvania / Philadelphia & Columbia / Philadelphia & Sea Shore / Pittsburgh, Fort Wayne & Chicago / Vandalia Line 4-4-0 "American" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class 1/D (Locobase 11591)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 15, p. 36. Works numbers were 9901-9902 in March 1889.

The NYP & N was a Delmarva road that connected the Pennsylvania's end point at Delmar in the center of the peninsula with Norfolk. It was created by merging 9-mile Worcester & Newton with the Eastern Shore which linked Delmar to Salisbury and thence southwest to Annensic, later dubbed Crisfield, on Chesapeake Bay. The last and longest element was the 65-mile section built in the 1880s between Pocomoke, Md and the ferry at Cape Charles at the southern tip of the Delmarva Peninsula.

These small Eight-wheelers eventually found their way onto the Pennsylvania's roster, but not for long. 12 left by 1906 and 1 was retired by 1913.


Class 1504 (Locobase 2834)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . Calculated tube heating surface was 1,684 sq ft. Later data from Schenectady Locomotive Works, Illustrated Catalogue of Simple and Compound Locomotives (Philadelphia: J B Lippincott, 1897), pp. 14-15 gave tube heating surface as 1,672.2 sq ft.

One of three engines assessed at the end of the 19th century. The other two were the 1510, a Baldwin compound (Locobase 2835) , and 1320, a Webb compound (Locobase 2834). The New Yorker was a straightforward, orthodox simple-expansion locomotive that offered a good- sized boiler as well as a look at building techniques from a manufacturer other than Altoona or the PRR's natural bedmate, Baldwin. One interesting difference from prevailing PRR practice was a noticeably smaller grate area.

This one was retired in 1911.


Class 1510/D (Locobase 2835)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 18, p. 11. Works number was 12824 in July 1892.

One of three engines assessed at the end of the 19th century. This was a Vauclain compound. The other two were the 1504, a Schenectady-built simple-expansion (Locobase 2834), and 1320, a Webb compound (Locobase 2836).

Baldwin delivered the 1510 with the 22" LP cylinders shown in this spec, which generated an LP/HP ratio of 2.86, in keeping with many other Vauclain compounds. Each set of an LP and and HP cylinder was served by a single 10 1/2" (267 mm) balanced piston valve. Later diagrams show the class with 24" LP cylinders, which raised that ratio to 3.41. Very few compounds ever tried to make exhausted HP steam do so much work per square inch.

In 1903, the Pennsy converted the 1510 to a two-cylinder simple-expansion locomotive. In 1909, the railroad replaced its tall express drivers with 68" wheels. The engine was scrapped in 1911.


Class 2 (Locobase 16351)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 16, p. 27 (by reference to Volume 15, p. 232). See also William Bender Wilson, History of the Pennsylvania Railroad Company: With Plan of ..., Volume 1 (Philadelphia: Henry T Coates, 1899), pp. 356-358. Works numbers were 10850-10851 in May 1890.

As an illustration of the hidden standardization of many Baldwin designs, the NB below provides certain proof. The two railroads (Tuckerton and the PS&S shown here) operated over similarly flat and relatively straight profiles in southern New Jersey and ordered pairs of Eight-wheeler passenger locomotives in October 1889 and end-December, respectively.

NB: Tuckerton Railroad's engines 4 and 5 (Locobase 11649) provided the heating surface data for the P&SS's 2-3 after a comparison of the two orders' showed them to have identical fireboxes and grates that burned "hard coal" as well as identical counts, diameters, and lengths of the tubes in the boiilers.

Unlike the Tuckerton, which remained independent for decades, the P&SS had entered receivership by November 1891. This followed some of the management's decision to acquire the Tuckahoe & Cape May, apparently sparking a liquidity crisis. The T&CM was declared insolvent in 1892. (Four later P&SS camelback Eight-wheelers produced in June 1890 were repossessed in February 1892 and sold to Philadelphia & Reading as their class D5-c.)

In August 1893, ownership of the 2 and 3 passed to the West Jersey as their 40-41. Bender's 1899 history notes that this line had a long history and an extensive network. In 1896, its system included "Camden to Cape May, Salem Branch, Woodbury to Salem, branch in Salem, branch, Elmer to Riddleton Junction, Bridgeton Branch, Glassboro to Bridgeton, branch in Bridgeton, Maurice River Branch, Manumuskin to Maurice River, Sea Isle and Ocean City Branch, Sea Isle Junction to Ocean City, Avalon Beach Branch, Sea Isle City to Stone Harbor, Anglesea Branch, Anglesea Junction to Holly Beach, total 184.84 miles, and operated the West Jersey and Atlantic Railroad, main line, Newfield to junction with Camden and Atlantic Railroad near Atlantic City Branch, Pleasantville to Somer's Point, Alloway and Quinton Railroad, Alloway Junction to Quinton, total miles, 43.96. Total owned and operated, 228.80 miles."

"To perfect its splendid system of catering to seashore traffic", Bender wrote, the Pennsylvania amalgamated several roads, including the West Jersey, as the West Jersey & Seashore in 1896. (By that time, the WJ included other railroads such as the Alloway and Quinton Railroad Company, the West Jersey and Atlantic Railroad Company, the Camden and Atlantic Railroad Company, the Chelsea Branch Railroad Company, and the Philadelphia, Marlton and Medford Railroad Company.)

The system was well worth the taking, Bender noted: "These railroads are peculiarly seashore lines, the West Jersey Railroad and its connections furnishing access to all portions of the New Jersey Coast from Atlantic City to Cape May, a distance of about thirty-six miles, and the Camden and Atlantic Railroad has comparatively little business outside of that pertaining to Atlantic City." This was principally passenger service and varied greatly with twice as many passengers taking the train in summer as in winter. Such disparity extended to the municipal electric lines in Atlantic City, which required "about fifty cars during the summer season and about eight during the winter."

Unlike many other such beachgoer lines, however, the WJ ran "considerable passenger and freight business over its lines to Salem, Bridgeton, Millville and some other smaller manufacturing towns, in all of which are glass works, of more or less extensive capacity, and manufactories of other kinds."

When the Pennsy incorporated the two Eight-wheelers into its main roster in 1903, the 41 received no new number and was scrapped in November 1905.

The 40 received #6040. but soon was sold to Senator Sproul in January 1905 to run on the Coal River Coal Company of Clothier, WVa as their #7. Taken over by the C&O in 1912, the 7 took no fewer than four numbers (904, 1005, 1305,and 53) before it went to the ferro-knacker in August 1915.


Class A/D1 (Locobase 1132)

Data from "Pennsylvania Railroad; Standard Types of Locomotives - Table XII [13]", Engineering, Volume XXIV [24], No 4 (27 July 1877), pp. 65-67, Park Benjamin (Ed), Appleton's Cyclopedia of Applied Mechanics (New York: D Appleton & Company, 1884), p. 348. See also diagram scanned in by Robert Schoenberg of http://prr.railfan.net . One of the classes established by Alexander J. Cassatt in 1867 when he became Master of Machinery. His goal was to standardize to allow greater interchangeability of parts. Duty was light passenger service.


Class AAn/D7 (Locobase 1145)

Based on Cassatt's A class, but fitted with firebox suitable for buring coal. Very similar to K class, but with a slightly greater tube length.

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net .

Class AAn/D7A (Locobase 2825)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . Differs from D7 in having smaller drivers, more even weight distribution even as it weighed 1 1/2 tons more. Its firebox rode above the drivers' axles, which allowed the grate to be 41 3/4 (1,060 mm) wide.


Class B/D2 (Locobase 1133)

Data from "Pennsylvania Railroad; Standard Types of Locomotives - Table XII [13]", Engineering, Volume XXIV [24], No 4 (27 July 1877), pp. 65-67, Park Benjamin (Ed), Appleton's Cyclopedia of Applied Mechanics (New York: D Appleton & Company, 1884), p. 348. See also diagram scanned in by Robert Schoenberg of http://prr.railfan.net . and PRR 3 - 1904 109-D Class and Description of Locomotives dated 1 March 1904 supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

One of the classes established by Alexander J. Cassatt in 1867 when he became Master of Machinery. Compared to As, Bs had larger pistons, smaller drivers, greater TE. Duty was as passenger-service helpers in the mountains.


Class Ba/D2a (Locobase 1143)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net and PRR 3 - 1904 109-D Class and Description of Locomotives dated 1 March 1904 supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

One of the classes established by Alexander J. Cassatt in 1867 when he became Master of Machinery. Passenger-service locomotive. Nine of these were later converted to D2s with 62" drivers.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class C (Locobase 9945)

Data from C H Caruthers, "Early Baldwin Locomotives on the Pennsylvania Railroad", Locomotive Engineering, Vol XI, No 2 (February 1898), p. 110. Works 387, 389-390 in August 1850; 392, 394 in September 1850; 400 in October; 406 in November; 423 in April 1851; 431 in June; 459 in December; 462 in February 1852; 468 and 470 in March.

These engines were named when they first came into service: Venango, Centre, Clinton, Columbia, Elk, Erie, Bradford, Clearfield, Crawford, Fayette, Somerset, Greene, Lycoming, and Union.

As Caruthers describes the engines, he notes the big Bury firebox , safety valves on the dome and whistle, big cabbage stack, closely spaced truck, raked cylinder pitch (1 3/4" in 10").

The last of these was retired in 1870, although their obviously obsolescent design was recognized as early as 1857.


Class C/D3 (Locobase 1134)

Data from "Pennsylvania Railroad; Standard Types of Locomotives - Table XII [13]", Engineering, Volume XXIV [24], No 4 (27 July 1877), pp. 65-67, Park Benjamin (Ed), Appleton's Cyclopedia of Applied Mechanics (New York: D Appleton & Company, 1884), p. 348. See also diagram scanned in by Robert Schoenberg of http://prr.railfan.net . and PRR 3 - 1904 109-D Class and Description of Locomotives dated 1 March 1904 supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

One of the classes established by Alexander J. Cassatt in 1867 when he became Master of Machinery. Duty was passenger and fast freight service. The tenders for this class were fitted with water scoop for refilling their tanks while moving over sections that had water troughs between the rails.


Class C/D4 (Locobase 2820)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net .


Class C/D4A (Locobase 2821)

These were 15 D4s that were converted to the 68" driver configuration.

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net .

Class CAn/D4 (Locobase 1140)

Data from "Pennsylvania Railroad; Standard Types of Locomotives - Table XII [13]", Engineering, Volume XXIV [24], No 4 (27 July 1877), pp. 65-67, Park Benjamin (Ed), Appleton's Cyclopedia of Applied Mechanics (New York: D Appleton & Company, 1884), p. 348. See also diagram scanned in by Robert Schoenberg of http://prr.railfan.net . and PRR 3 - 1904 109-D Class and Description of Locomotives dated 1 March 1904 supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

One of the classes established by Alexander J. Cassatt in 1867 when he became Master of Machinery. Duty was passenger and fast freight service, had longer, shallower firebox suitable for burning anthracite coal. The tenders later carried 6 tons (5.45 tonnes) of coal.


Class CAn/D4A (Locobase 2822)

This anthracite burner is identical to the other D4A except for a slightly larger firebox.

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class D16a (Locobase 2833)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also Charles B. Chaney's summary in Railroad & Locomotive Historical Society Bulletin #59 (1942); and Alvin F Staufer (text by Bert Pennypacker, research by Martin Flattley), Steam and Electric Locomotives of the Pennsylvania Railroad 1900-1957 (Carrollton, Ohion: Standard Printing & Publishing Company, 1962), pp. 107-109. Works numbers were 346-348, 351-358, 363-367, 371-375 in 1895; 386, 393--397,399-402 in 1896; 426-430, 442, 445, 447, 449-452 in 1897, 476-484 in 1898; 2037-2050.

As with all Pennsy locomotives of this vintage or later, this design used a Belpaire firebox. The design represented the efforts of the Chief of Motive Power T N Ely, Mechanical Engineer Alex Vogt, and the Lines East's General Superintendent of Motive Power F D Casanave. See Locobase 1144 for more details on the design's origins.

Its chief difference from the original D16 was the mounting of 80" drivers, making it a true express engine. Even with such tall drivers, the L class's boiler and firebox were placed on top of the frame bars, rather than between them.

Pennypacker's commentary is plush with compliments: "superb mechanical perfection" over the Middle Division and offers the record of the 816, which "piled up more than three hundred thousand miles of service along that division in a period of three years and fouer months, without shopping or heavy repairs of any kind." On the dual "racetracks" between Jersey City and Atlantic City, engineer Martin Lee established "a legend of high-speed running." He is said to hit 102 mph (164 kph) over an 8-mile stretch ("fling", as Pennypacker calls it) and delivered PRR president AJ Cassatt's train to from Broad Street to Jersey City at an average of 70. 1 mph (113 kph).

These first Ls/

Many were later superheated as D16sb with 68" drivers; see Locobase 103.


Class D16b (Locobase 13320)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . The Pennsy didn't back away from long production runs once they were satisified with a design. After the Class L/D16 entered production in 1895 (Locobase 1144), its impact on PRR passenger trains led to subclasses of 80"-driver express locomotives: D16a (Locobase 2833) and D16c/D16d (Locobase 13221.)

But the biggest subclass was this 68" version produced from 1900 to 1908. In addition to the 262 for the Pennsy,

Altoona turned 31 more in 1905-1906 for the Long Island Railroad.as their 200-230. Exactly half of these were later superheated beginning in 1914.


Class D16c/D16d (Locobase 13321)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also Charles B. Chaney's summary in Railroad & Locomotive Historical Society Bulletin #59 (1942).

As with all Pennsy locomotives of this vintage or later, this design used a Belpaire firebox. It's not clear why there were two different subclasses. The chief difference from the D16a (Locobase 2833) was slightly higher weights.

Those that were not later converted to D16 by being fitted with 68" drivers or left alone were upgraded with superheaters and other details very similar to the D16sb (Locobase 103).


Class D16sb (Locobase 103)

Data from Pennsylvania Railroad All-Time Steam Locomotive Diagrams supplied in May 2005 by Allen Stanley from his Rail Data Collection. (Many thanks to Chris Hohl for his 22 September 2017 email reporting unlikely boiler pressure values for 177 entries. A Locobase macro caused the error .)

Modernized from 1914 on with the 20.5-in diameter pistons and boilers limited to 175 psi, but superheated. According to Edson (Keystone Steam & Electric, 1974), the conversion created an "...excellent engine for suburban service and local trains." Fifteen of the updates were of Long Island Railroad D16b.


Class D26 (Locobase 11107)

Data from Schenectady Locomotive Works, Illustrated Catalogue of Simple and Compound Locomotives (Philadelphia: J B Lippincott, 1897), pp. 8-9.

Schenectady's catalogue of recent American-type engines includes this quartet, whose dimensions match those of the St Lawrence & Adirondack engine shown in Locobase 11106. The chief difference is the driving wheel diameter, which is 6" greater in these main-line express that hauled "...heavy fast trains ...between Indianapolis and St Louis."


Class D26a (Locobase 9507)

Data from "Vandalia Express Engines" Railway and Locomotive Engineering, May 1899, page 225.

Tall express Eight-wheeler quartet that went into service pulling the fast expresses that linked Indianapolis and St Louis "...and they are gaining," said the R&LE's correspondent, "a high reputation for the efficient way in which they do the required work ...we understand that they went into service with exceptionally small trouble from the annoyances common to the breaking-in process."


Class G/D5 (Locobase 1138)

Data from "Pennsylvania Railroad; Standard Types of Locomotives - Table XII [13]", Engineering, Volume XXIV [24], No 4 (27 July 1877), pp. 65-67, Park Benjamin (Ed), Appleton's Cyclopedia of Applied Mechanics (New York: D Appleton & Company, 1884), p. 348. See also diagram scanned in by Robert Schoenberg of http://prr.railfan.net . and PRR 3 - 1904 109-D Class and Description of Locomotives dated 1 March 1904 supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. Built by Pennsylvania shops from 1869 to 1874 and 1881 to 1884.

One of the classes established by Alexander J. Cassatt in 1867 when he became Master of Machinery. Duty was passenger branch-line service, which is shown by the low axle loading and tractive effort.


Class K/D6 (Locobase 1142)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . One of the classes established by Alexander J. Cassatt in 1867 when he became Master of Machinery. High-drivered design for express passenger service. Note that while the grate was larger than that of the earlier B & C classes in order to burn anthracite coal, the K-class designer chose to use more, smaller boiler tubes. One can also see closer spacing between the drivers, resulting in a shorter wheelbase even though the individual drivers are much taller. This came from placing the firebox above the engine's frame rails rather than between them; the location was one of the first such constructions in a locomotive.

[] (visited 11 Nov 2004), the MTH models site, confirms Locobase's analysis with the comment that the K represented "an elegant and successful step in the evolution of Pennsy motive power". Ks also featured a two-bar alligator crosshead, powered reversing gear, and sandboxes on the running board rather than sand in a top-mounted dome.

A dissent from this positive assessment is found closer to the time of their use in Railroad & Engineering Journal, Volume LXVI, No 11 (November 1892), p. 487.. The author comments that although they had tall drivers, "...owing to insufficient boiler capacity were not successful in the service for which they were intended - that is, heavy and fast passenger traffic."


Class K/D6A (Locobase 2823)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . These 7 were converted from D6 engines with smaller drivers, which raised tractive effort. The factor of adhesion suggests, however, that this design still had some room for growth.


Class L/D16 (Locobase 1144)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also Charles B. Chaney's summary in Railroad & Locomotive Historical Society Bulletin #59 (1942) and J Parker Lamb, Perfecting the American Steam Locomotive (Bloomington, IN: Indiana University Press, 2003), pp. 25, 27; and Alvin F Staufer (text by Bert Pennypacker, research by Martin Flattley), Steam and Electric Locomotives of the Pennsylvania Railroad 1900-1957 (Carrollton, Ohion: Standard Printing & Publishing Company, 1962), pp. 107-109.

426 D-16 engines built in five sub-classes between 1895 and 1910. D-16 had 68" drivers; D-16a had 80" drivers (Locobase 2833). All had the characteristic (for the Pennsy) Belpaire firebox. According to J Parker Lamb, "An unlikely trio of international technical talent" were primarily responsible for designing this large, powerful passenger engine. They were the French-born general superintendent of motive power Frank D. Casanave, chief mechanical engineer Axel S. Vogt from Sweden, and American-born chief of motive power Theodore N. Ely. Lamb describes the division of labor: "Casanave supervised the design, whose details were refined by Vogt, while Ely ...used his artistic talents to provide the external contours, and to design the paint scheme and striping of the finished product."

They began with 18.5 x 26 cylinders, 185-psi boilers, yielding a 22,250 lb tractive effort; because of Vogt's "careful attention to details", the first of the class weighed in at a value only 68 pounds away from the estimate. All of the engines were fitted with the same number of tubes, each of which offered the unusual diameter of 1 7/8" inches.

A mark of the D16's reliability was the long production run (signifying satisfaction with the original design as well as a relatively conservative approach to innovation). Another was their longevity in service, with 143 remaining on the roster in 1929. Almost all rolled on 68" drivers by then, pulling a great variety of local passenger trains. Pennypacker noted that several were later sold to the Kishacoqullas Valley railroad of Lewistown, Pa.


Class N/D8 (Locobase 1147)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . Replaced C class. Had a larger boiler. Duty was passenger and fast freight service.


Class O/D10 (Locobase 2827)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . Responded to the O class's low factor of adhesion by increasing the weight on the drivers. D10A had only 600 lb more total weight in working order. Among the first Pennsylvania engines to have a Belpaire boiler.


Class O/D10a (Locobase 3488)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . D10A had only 600 lb more total weight in working order, but had the taller drivers. Among the first Pennsylvania engines to have a Belpaire boiler.


Class O/D8A (Locobase 1148)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . Similar to N, but with slightly larger cylinders. Duty was passenger and fast freight service.


Class O/D9 & D9A (Locobase 2826)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . Had the earlier O class cylinders, but saw a big jump in boiler pressure with commensurate jump in tractive effort. Also included a Belpaire firebox. Now, however, the factor of adhesion had dropped to the point of slipperiness. D9A had slightly more weight on the drivers.


Class O/D9a (Locobase 3487)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . D9A put slightly more weight on taller drivers than did the D9s, but also had the Belpaire firebox.


Class P/D11 (Locobase 1149)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also Charles B. Chaney, "The Famous Class P Passenger Engines - Pennsylvania Railroad" Railroad & Locomotive Historical Society Bulletin #59 (1942), pp. 6-11.

Similar to O, but with slightly larger cylinders and higher boiler pressure and "toboggan-type" fireboxes with grates that sloped toward the front. Their service area included the Philadelphia, Wilmington & Baltimore and the Baltimore & Potomac pulling 20-car fast freight trains.


Class P/D11a (Locobase 4152)

See also Charles B. Chaney, "The Famous Class P Passenger Engines - Pennsylvania Railroad" Railroad & Locomotive Historical Society Bulletin #59 (1942), pp. 6-11.

Like the D11s (Locobase 1149), which ran on 62" drivers, the D11as had radial-stay "toboggan-type" fireboxes with grates that sloped toward the front. Their 18 1/2" cylinder diameter was an unusual diameter in North American practice.

Chaney reported that a D11a ran two round trips daily between Philadelphia and Washington for one month in 1887 and accumulated 17,000 miles (27,370 km).


Class P/D12 (Locobase 2828)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also See also Charles B. Chaney, "The Famous Class P Passenger Engines - Pennsylvania Railroad" Railroad & Locomotive Historical Society Bulletin #59 (1942), pp. 6-11.

These two engines were part of the landmark P class variant that introduced the Belpaire boiler, later to become a standard part of Pennsy practice. They were assigned to the Northern Central Railway.


Class P/D12a (Locobase 2829)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also See also Charles B. Chaney, "The Famous Class P Passenger Engines - Pennsylvania Railroad" Railroad & Locomotive Historical Society Bulletin #59 (1942), pp. 6-11. Produced in 1889-1891.

This large class first used a Belpaire firebox on one of the few US railroads that would adopt the square-shouldered furnace in significant numbers. In this first version, the firebox had 90-degree corners. According to Chaney, "..this design developed a weakness at this point and the design was later modified."


Class P/D13 (Locobase 2830)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also See also Charles B. Chaney, "The Famous Class P Passenger Engines - Pennsylvania Railroad" Railroad & Locomotive Historical Society Bulletin #59 (1942), pp. 6-11

This pair used the same boiler design as the much more numerous D13a, D13c classes shown in Locobase 3489, but rolled on smaller drivers that were better suited to the NCR's requirements.


Class P/D13a, D13c (Locobase 3489)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also See also Charles B. Chaney, "The Famous Class P Passenger Engines - Pennsylvania Railroad" Railroad & Locomotive Historical Society Bulletin #59 (1942), pp. 6-11.

Still newer P class, now with more, but smaller tubes and more weight on the drivers. It introduced a new, stronger boiler mated with a flush joint to the Belpaire firebox. The D13a, with their taller drivers, were far more numerous than the duet of D13s (Locobase 2830). D13cs were virtually identical, the new designation representing a modest change in the boiler design introduced in 1893.


Class P/D14 (Locobase 2831)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also See also Charles B. Chaney, "The Famous Class P Passenger Engines - Pennsylvania Railroad" Railroad & Locomotive Historical Society Bulletin #59 (1942), pp. 6-11

Now the P class stepped up in both boiler pressure and driver diameter for the higher speeds and train tonnages that marked the end of the 19th century. Belpaire firebox.

Later converted to D14c engines with 68" drivers.


Class P/D14a (Locobase 2832)

Data from diagram scanned in by Robert Schoenberg of http://prr.railfan.net . See also Charles B. Chaney, "The Famous Class P Passenger Engines - Pennsylvania Railroad" Railroad & Locomotive Historical Society Bulletin #59 (1942), pp. 6-11; and "Boiler for Class P Locomotive, Pennsylvania Railroad,"American Engineer and Railroad Journal, Volume LXIX, Number 7 (July 1895), pp. 310-312.

Still taller drivers than on the D14 and 1/2" larger cylinders. Axel Vogt redesigned the crosshead, replacing the 2-bar Alligator type with a 3-bar crosshead.

Like most Pennsylvania engines, this class used the Belpaire firebox. The AERJ report explained that Belpaire boilers had caused "considerable trouble" by leaking at the joint between the barrel and the outer shell of the firebox. "This difficulty has been entirely overcome in the case of these boilers," the report continued, "by flanging the connecting sheet in line, thus making the boiler straight top. The strains of expansion and contraction are in this way brought fair against the riveting, and all working due to buckling is avoided."

As a result of replacing the 18" (457 mm) diameter stack with a tapered, 13 1/2" (343 mm) version, the engines now had exhausts that "sounded like the bark of a rifle," according to Charles Chaney.

NB: The evaporative heating surface area in the AERJ report was given as 1,551.84 sq ft because of a firebox heating surface calculation of 116.64 sq ft. Arch tubes added later probably accounted for the difference between that figure and the 148 sq ft shown in the diagram.

Later converted to D14b with 68" drivers.


Class T/D15 (Locobase 1152)

Some data from "Compound Express Engine, Pennsylvania Railroad" The Locomotive & Railway Carriage & Wagon Review, Vol III (September 1898), p. 139

One of the Pennsy's rare excursions into compounding. Two-cylinder Lindner cross-compound for express passenger service designed by the Chief of Motive Power at the Altoona Shops Theodore N Ely.

Belpaire firebox was of typical Pennsy form, but the dome, the low running board with raised cups for the crankpins gave it a European look.

The author of the Locomotive article noted that the locomotive was a spirited performer, often making up time on the schedule while pulling 12 heavy Pullman cars. "With all this, however, in its favour" he is bound to report, "we doubt if 1515 has ever been really liked by the American drivers. There's something strange about it, with its boxed up wheels, rocking shaft, less valve year, &c, that the men have never taken to, the drivers of the States being very much attached to their American type of engine and its easily accessible parts."


Class unknown (Locobase 11176)

Data from "Fuel for Railroads", William Jenney (ed.), The Mining Magazine and Journal, Vol Six, (January 1856) p. 64-66. See also Locobase 5570 for other early comments on the preference for coal as fuel.

According to the Mining Magazine, as of early 1856 "This is a subject of growing importance, and every investigation of it tends to show the value and importance of coal as an article of fuel." His discussion of the substitution of coal for wood included communications from several locomotive superintendents describing various tests by different railroads in 1855.

The P&C's J B Baker ran several trips measuring 82 miles (132 km) each and "elevation overcome" of 1,045 ft using equal parts of Hollidaysburg and Pittsburgh coal, Pittsburgh coal alone, and Broad Top coal. Broad Top burned the most economically with 6,432 lb (2,918 kg) consumed to evaporate 4,877 gallons (18,459 litres) - this on a grate originally designed for wood burning. The reader will also be able to perform the back-of-the-envelope calculation that over an 82-mile trip pulling 50 cars in a train of 369 short tons total, and given the tender capacity of the day, the crew would have had to stop for water at least three times. No wonder the average speed was 10.9 mph (17.5 km/h).


Class unknown (Locobase 9519)

Data from the Twelfth Annual Report of the American Railway Master Mechanics' Association, May 13th-May15th, 1879, page 83-84. NB: Boiler pressure is an estimate and the heating surface of the tubes is measured from the inside. Locobase believes this engine is one of the quartet produced by Baldwin in January 1867, works numbers 1573-1574, 1577-1578.

James M. Boone of the P, Ft W & C described the boiler for which he gave the specifications as "a good steamer; will make steam freely with nut coal; does the best work with about 4" of coal on the grate."

Principal Dimensions by Steve Llanso of Sweat House Media
Class1/D15041510/D2A/D1
Locobase ID11,591 2834 2835 16,351 1132
RailroadNew York, Philadelphia & Norfolk (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Philadelphia & Sea Shore (PRR)Pennsylvania (PRR)
CountryUSAUSAUSAUSAUSA
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class211213
Road Numbers1, 12150415102-3/40-41/6040
GaugeStdStdStdStdStd
Number Built211213
BuilderBurnham, Parry, Williams & CoSchenectadyBurnham, Williams & CoBurnham, Parry, Williams & CoAltoona
Year18891892189218901867
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 8.50 / 2.598 / 2.44 7.50 / 2.29 7.50 / 2.298 / 2.44
Engine Wheelbase (ft / m)23.17 / 7.0623.42 / 7.1422.29 / 6.7920.75 / 6.3222.47 / 6.85
Ratio of driving wheelbase to overall engine wheebase 0.37 0.34 0.34 0.36 0.36
Overall Wheelbase (engine & tender) (ft / m)47.98 / 14.6247.85 / 14.5844.51 / 13.57
Axle Loading (Maximum Weight per Axle) (lbs / kg)30,670 / 13,91241,000 / 18,59741,800 / 18,96024,480 / 11,104
Weight on Drivers (lbs / kg)60,730 / 27,54781,500 / 36,96883,900 / 38,05657,920 / 26,27242,370 / 19,219
Engine Weight (lbs / kg)93,570 / 42,443126,700 / 57,470122,400 / 55,52084,370 / 38,27071,900 / 32,613
Tender Loaded Weight (lbs / kg)88,000 / 39,91688,000 / 39,91654,000 / 24,494
Total Engine and Tender Weight (lbs / kg)214,700 / 97,386210,400 / 95,436125,900 / 57,107
Tender Water Capacity (gals / ML)2400 / 9.093500 / 13.263600 / 13.642800 / 10.612400 / 9.09
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)8 / 7.30 7.50 / 6.804 / 3.60
Minimum weight of rail (calculated) (lb/yd / kg/m)51 / 25.5068 / 3470 / 3548 / 2435 / 17.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)62 / 157578 / 198178 / 198166 / 167668 / 1727
Boiler Pressure (psi / kPa)130 / 9180 / 12.40180 / 12.40130 / 9125 / 8.60
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x61018" x 24" / 457x61013" x 24" / 330x61017" x 24" / 432x61017" x 24" / 432x610
Low Pressure Cylinders (dia x stroke) (in / mm)22" x 24" / 610x610
Tractive Effort (lbs / kg)13,859 / 6286.3415,253 / 6918.6511,794 / 5349.6711,613 / 5267.5710,838 / 4916.04
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.38 5.34 7.11 4.99 3.91
Heating Ability
Firebox Area (sq ft / m2)144.30 / 13.41166 / 15.43108 / 10.04131.72 / 12.24
Grate Area (sq ft / m2)17.60 / 1.6426.20 / 2.4338.50 / 3.5832.10 / 2.9816.10 / 1.50
Evaporative Heating Surface (sq ft / m2)1817 / 168.871696 / 157.621179 / 109.571052 / 97.73
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1817 / 168.871696 / 157.621179 / 109.571052 / 97.73
Evaporative Heating Surface/Cylinder Volume257.05459.99186.99166.85
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation22884716693041732013
Same as above plus superheater percentage22884716693041732013
Same as above but substitute firebox area for grate area25,97429,88014,04016,465
Power L18404559838993844
Power MT454.67294.19296.82400.03

Principal Dimensions by Steve Llanso of Sweat House Media
ClassAAn/D7AAn/D7AB/D2Ba/D2aC
Locobase ID1145 2825 1133 1143 9945
RailroadPennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)
CountryUSAUSAUSAUSAUSA
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class5861204523
Road Numbers
GaugeStdStdStdStdStd
Number Built5861204523
BuilderAltoonaAltoonaAltoonaAltoonaM W Baldwin
Year18821883186718811849
Valve GearStephensonStephensonStephensonStephensonV-hook
Locomotive Length and Weight
Driver Wheelbase (ft / m) 7.75 / 2.36 7.75 / 2.36 8.50 / 2.59 8.50 / 2.59 5.33 / 1.62
Engine Wheelbase (ft / m)22.68 / 6.9122.68 / 6.9122.47 / 6.85
Ratio of driving wheelbase to overall engine wheebase 0.34 0.34 0.38
Overall Wheelbase (engine & tender) (ft / m)48.50 / 14.7848.50 / 14.7844.52 / 13.5744.61 / 13.60
Axle Loading (Maximum Weight per Axle) (lbs / kg)33,100 / 15,01432,650 / 14,81028,000 / 12,70128,330 / 12,850
Weight on Drivers (lbs / kg)64,000 / 29,03065,180 / 29,56553,200 / 24,13153,754 / 24,38226,200 / 11,884
Engine Weight (lbs / kg)93,350 / 42,34396,330 / 43,69580,500 / 36,51482,200 / 37,28545,900 / 20,820
Tender Loaded Weight (lbs / kg)51,400 / 23,31551,400 / 23,315
Total Engine and Tender Weight (lbs / kg)131,900 / 59,829133,600 / 60,600
Tender Water Capacity (gals / ML)2400 / 9.092400 / 9.092400 / 9.092400 / 9.09
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)6 / 5.506 / 5.504 / 3.604 / 3.60
Minimum weight of rail (calculated) (lb/yd / kg/m)53 / 26.5054 / 2744 / 2245 / 22.5022 / 11
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)68 / 172762 / 157562 / 157568 / 172754 / 1372
Boiler Pressure (psi / kPa)140 / 9.70140 / 9.70125 / 8.60125 / 8.6075 / 5.20
High Pressure Cylinders (dia x stroke) (in / mm)17" x 24" / 432x61017" x 24" / 432x61018" x 24" / 457x61018" x 24" / 457x61015" x 20" / 381x508
Tractive Effort (lbs / kg)12,138 / 5505.7113,313 / 6038.6813,326 / 6044.5812,150 / 5511.155313 / 2409.94
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.27 4.90 3.99 4.42 4.93
Heating Ability
Firebox Area (sq ft / m2)155 / 14.41155 / 14.41115.11 / 10.70202 / 18.77
Grate Area (sq ft / m2)34.80 / 3.2334.80 / 3.2317.60 / 1.6417.60 / 1.64
Evaporative Heating Surface (sq ft / m2)1289 / 119.801289 / 119.801057 / 98.231172 / 108.92
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1289 / 119.801289 / 119.801057 / 98.231172 / 108.92
Evaporative Heating Surface/Cylinder Volume204.44204.44149.53165.80
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation4872487222002200
Same as above plus superheater percentage4872487222002200
Same as above but substitute firebox area for grate area21,70021,70014,38925,250
Power L15194473629834373
Power MT357.84320.38247.23358.70

Principal Dimensions by Steve Llanso of Sweat House Media
ClassC/D3C/D4C/D4ACAn/D4CAn/D4A
Locobase ID1134 2820 2821 1140 2822
RailroadPennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)
CountryUSAUSAUSAUSAUSA
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class6737153737
Road Numbers
GaugeStdStdStdStdStd
Number Built67373737
BuilderAltoonaAltoonaAltoona
Year18671873187318731873
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 8.50 / 2.59 8.50 / 2.59 8.50 / 2.59 8.50 / 2.59 8.50 / 2.59
Engine Wheelbase (ft / m)22.47 / 6.8522.47 / 6.8522.47 / 6.8522.47 / 6.8522.47 / 6.85
Ratio of driving wheelbase to overall engine wheebase 0.38 0.38 0.38 0.38 0.38
Overall Wheelbase (engine & tender) (ft / m)44.97 / 13.7146.84 / 14.2846.84 / 14.2846.84 / 14.2846.84 / 14.28
Axle Loading (Maximum Weight per Axle) (lbs / kg)26,880 / 12,19329,160 / 13,22728,410 / 12,88729,160 / 13,22730,188 / 13,693
Weight on Drivers (lbs / kg)50,950 / 23,11156,200 / 25,49255,520 / 25,18356,200 / 25,49257,456 / 26,062
Engine Weight (lbs / kg)79,100 / 35,87981,800 / 37,10482,060 / 37,22278,750 / 37,10483,500 / 37,875
Tender Loaded Weight (lbs / kg)51,400 / 23,31551,400 / 23,31551,400 / 23,31551,400 / 23,31551,400 / 23,315
Total Engine and Tender Weight (lbs / kg)130,500 / 59,194133,200 / 60,419133,460 / 60,537130,150 / 60,419134,900 / 61,190
Tender Water Capacity (gals / ML)2400 / 9.092400 / 9.092400 / 9.092400 / 9.092400 / 9.09
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)4 / 3.606 / 5.506 / 5.504 / 5.506 / 5.50
Minimum weight of rail (calculated) (lb/yd / kg/m)42 / 2147 / 23.5046 / 2347 / 23.5048 / 24
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)62 / 157562 / 157568 / 172762 / 157568 / 1727
Boiler Pressure (psi / kPa)125 / 8.60125 / 8.60125 / 8.60125 / 8.60125 / 8.60
High Pressure Cylinders (dia x stroke) (in / mm)17" x 24" / 432x61017" x 24" / 432x61017" x 24" / 432x61017" x 24" / 432x61017" x 24" / 432x610
Tractive Effort (lbs / kg)11,886 / 5391.4111,886 / 5391.4110,838 / 4916.0411,886 / 5391.4110,838 / 4916.04
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.29 4.73 5.12 4.73 5.30
Heating Ability
Firebox Area (sq ft / m2)115.11 / 10.70155.56 / 14.46155.56 / 14.46158.55 / 14.73161.50 / 15.01
Grate Area (sq ft / m2)17.60 / 1.6428.54 / 2.6528.54 / 2.6529.13 / 2.7129.13 / 2.71
Evaporative Heating Surface (sq ft / m2)1057 / 98.231158 / 107.621158 / 107.621161 / 107.861158 / 107.62
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1057 / 98.231158 / 107.621158 / 107.621161 / 107.861158 / 107.62
Evaporative Heating Surface/Cylinder Volume167.64183.66183.66184.14183.66
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation22003568356836413641
Same as above plus superheater percentage22003568356836413641
Same as above but substitute firebox area for grate area14,38919,44519,44519,81920,188
Power L133453966435040034416
Power MT289.48311.16345.46314.06338.89

Principal Dimensions by Steve Llanso of Sweat House Media
ClassD16aD16bD16c/D16dD16sbD26
Locobase ID2833 13,320 13,321 103 11,107
RailroadPennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Vandalia Line (PRR)
CountryUSAUSAUSAUSAUSA
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class73293572414
Road Numbers
GaugeStdStdStdStdStd
Number Built73293574
BuilderJuniata/AltoonaAltoonaAltoonaJuniataSchenectady
Year18951900189919141895
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 7.75 / 2.36 7.75 / 2.36 7.75 / 2.36 7.75 / 2.36 8.50 / 2.59
Engine Wheelbase (ft / m)22.79 / 6.9522.79 / 6.9522.79 / 6.9522.79 / 6.9523.92 / 7.29
Ratio of driving wheelbase to overall engine wheebase 0.34 0.34 0.34 0.34 0.36
Overall Wheelbase (engine & tender) (ft / m)50.29 / 15.3350.29 / 15.3355.02 / 16.7749.96 / 15.23
Axle Loading (Maximum Weight per Axle) (lbs / kg)48,400 / 21,95450,400 / 22,86148,100 / 21,81852,000 / 23,587
Weight on Drivers (lbs / kg)93,100 / 42,22997,100 / 44,04494,900 / 43,04698,150 / 44,52084,500 / 38,329
Engine Weight (lbs / kg)134,500 / 61,008138,000 / 62,596138,700 / 62,913142,100 / 64,456129,200 / 58,604
Tender Loaded Weight (lbs / kg)82,000 / 37,195132,000 / 59,87480,000 / 36,287138,900 / 63,004
Total Engine and Tender Weight (lbs / kg)216,500 / 98,203270,000 / 122,470218,700 / 99,200281,000 / 127,460
Tender Water Capacity (gals / ML)3600 / 13.645500 / 20.833000 / 11.365600 / 21.214000 / 15.15
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 7.50 / 6.8012.50 / 11.40 7.50 / 6.8013 / 11.80
Minimum weight of rail (calculated) (lb/yd / kg/m)78 / 3981 / 40.5079 / 39.5082 / 4170 / 35
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)80 / 203268 / 172780 / 203268 / 172773 / 1854
Boiler Pressure (psi / kPa)185 / 12.80185 / 12.80185 / 12.80175 / 12.10190 / 13.10
High Pressure Cylinders (dia x stroke) (in / mm)18.5" x 26" / 470x66018.5" x 26" / 470x66018.5" x 26" / 470x66020.5" x 26" / 521x66020" x 24" / 508x610
Tractive Effort (lbs / kg)17,491 / 7933.7920,578 / 9334.0317,491 / 7933.7923,902 / 10841.7821,238 / 9633.41
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.32 4.72 5.43 4.11 3.98
Heating Ability
Firebox Area (sq ft / m2)171.40 / 15.93166.70 / 15.49166.20 / 15.44181 / 16.82171.20 / 15.91
Grate Area (sq ft / m2)33 / 3.0733 / 3.0733 / 3.0733.20 / 3.0930.05 / 2.79
Evaporative Heating Surface (sq ft / m2)1918 / 178.251900 / 176.511900 / 176.511400 / 130.112168 / 201.49
Superheating Surface (sq ft / m2)253 / 23.51
Combined Heating Surface (sq ft / m2)1918 / 178.251900 / 176.511900 / 176.511653 / 153.622168 / 201.49
Evaporative Heating Surface/Cylinder Volume237.11234.89234.89140.95248.43
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation61056105610558105710
Same as above plus superheater percentage61056105610566825710
Same as above but substitute firebox area for grate area31,70930,84030,74736,42632,528
Power L184627085832891498011
Power MT400.76321.72386.94411.00418.02

Principal Dimensions by Steve Llanso of Sweat House Media
ClassD26aG/D5K/D6K/D6AL/D16
Locobase ID9507 1138 1142 2823 1144
RailroadVandalia Line (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)
CountryUSAUSAUSAUSAUSA
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class4181976
Road Numbers
GaugeStdStdStdStdStd
Number Built418196
BuilderSchenectadyAltoonaAltoona
Year18991870188018801896
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 8.50 / 2.597 / 2.13 7.75 / 2.36 7.75 / 2.36 7.75 / 2.36
Engine Wheelbase (ft / m)24.42 / 7.4419.80 / 6.0422.72 / 6.9322.72 / 6.9322.79 / 6.95
Ratio of driving wheelbase to overall engine wheebase 0.35 0.35 0.34 0.34 0.34
Overall Wheelbase (engine & tender) (ft / m)52.21 / 15.9140.51 / 12.3548.48 / 14.7848.48 / 14.7850.29 / 15.33
Axle Loading (Maximum Weight per Axle) (lbs / kg)20,500 / 929932,900 / 14,92332,900 / 14,92348,300 / 21,909
Weight on Drivers (lbs / kg)85,800 / 38,91840,700 / 18,46165,800 / 29,84665,800 / 29,84693,600 / 42,456
Engine Weight (lbs / kg)132,300 / 60,01060,000 / 27,21696,700 / 43,86296,700 / 43,862135,900 / 61,643
Tender Loaded Weight (lbs / kg)40,800 / 18,50756,300 / 25,53756,300 / 25,53782,000 / 37,195
Total Engine and Tender Weight (lbs / kg)100,800 / 45,723153,000 / 69,399153,000 / 69,399217,900 / 98,838
Tender Water Capacity (gals / ML)6000 / 22.731600 / 6.062400 / 9.092400 / 9.093600 / 13.64
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)10 / 9.10 3.25 / 36 / 5.506 / 5.50 7.50 / 6.80
Minimum weight of rail (calculated) (lb/yd / kg/m)72 / 3634 / 1755 / 27.5055 / 27.5078 / 39
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)78 / 198156 / 142278 / 198172 / 182968 / 1727
Boiler Pressure (psi / kPa)190 / 13.10125 / 8.60140 / 9.70140 / 9.70185 / 12.80
High Pressure Cylinders (dia x stroke) (in / mm)20" x 26" / 508x66015" x 22" / 381x55918" x 24" / 457x61018" x 24" / 457x61018.5" x 26" / 470x660
Tractive Effort (lbs / kg)21,533 / 9767.229392 / 4260.1411,863 / 5380.9712,852 / 5829.5820,578 / 9334.03
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.98 4.33 5.55 5.12 4.55
Heating Ability
Firebox Area (sq ft / m2)175 / 16.2669.04 / 6.41155 / 14.41155.60 / 14.46171.40 / 15.93
Grate Area (sq ft / m2)30 / 2.7913.30 / 1.2434.80 / 3.2334.80 / 3.2333 / 3.07
Evaporative Heating Surface (sq ft / m2)2241 / 208.27721 / 66.981240 / 115.241240 / 115.241918 / 178.25
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)2241 / 208.27721 / 66.981240 / 115.241240 / 115.241918 / 178.25
Evaporative Heating Surface/Cylinder Volume237.05160.23175.42175.42237.11
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation57001663487248726105
Same as above plus superheater percentage57001663487248726105
Same as above but substitute firebox area for grate area33,250863021,70021,78431,709
Power L181412764518847967193
Power MT418.36299.44347.65321.38338.84

Principal Dimensions by Steve Llanso of Sweat House Media
ClassN/D8O/D10O/D10aO/D8AO/D9 & D9A
Locobase ID1147 2827 3488 1148 2826
RailroadPennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)
CountryUSAUSAUSAUSAUSA
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class4551588617
Road Numbers
GaugeStdStdStdStdStd
Number Built4551588617
BuilderJuniataJuniata
Year18831883189018831883
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 8.50 / 2.59 8.50 / 2.59 8.50 / 2.59 8.50 / 2.59 8.50 / 2.59
Engine Wheelbase (ft / m)23.46 / 7.1523.45 / 7.1523.45 / 7.1523.4623.45 / 7.15
Ratio of driving wheelbase to overall engine wheebase 0.36 0.36 0.36 0.36 0.36
Overall Wheelbase (engine & tender) (ft / m)45.96 / 14.0147.37 / 14.4447.37 / 14.4445.51 / 13.8747.37 / 14.44
Axle Loading (Maximum Weight per Axle) (lbs / kg)30,800 / 13,97132,700 / 14,83232,700 / 14,83231,300 / 14,19731,100 / 14,107
Weight on Drivers (lbs / kg)57,700 / 26,17265,350 / 29,64265,350 / 29,64258,300 / 26,44459,800 / 27,125
Engine Weight (lbs / kg)91,300 / 41,413103,000 / 46,720103,000 / 46,72097,900 / 44,40796,700 / 43,862
Tender Loaded Weight (lbs / kg)50,500 / 22,90673,350 / 33,27173,350 / 33,27150,500 / 22,90673,350 / 33,271
Total Engine and Tender Weight (lbs / kg)141,800 / 64,319176,350 / 79,991176,350 / 79,991148,400 / 67,313170,050 / 77,133
Tender Water Capacity (gals / ML)2400 / 9.093600 / 13.643600 / 13.643600 / 13.64
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)4 / 3.60 7.50 / 6.80 7.50 / 6.80 7.50 / 6.80
Minimum weight of rail (calculated) (lb/yd / kg/m)48 / 2454 / 2754 / 2749 / 24.5050 / 25
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)62 / 157562 / 157568 / 172762 / 157562 / 1575
Boiler Pressure (psi / kPa)130 / 9160 / 11160 / 11130 / 9160 / 11
High Pressure Cylinders (dia x stroke) (in / mm)17" x 24" / 432x61018" x 24" / 457x61018" x 24" / 457x61018" x 24" / 457x61018" x 24" / 457x610
Tractive Effort (lbs / kg)12,362 / 5607.3217,057 / 7736.9315,552 / 7054.2813,859 / 6286.3417,057 / 7736.93
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.67 3.83 4.20 4.21 3.51
Heating Ability
Firebox Area (sq ft / m2)142 / 13.2093 / 8.6493 / 8.64142 / 13.20127.60 / 11.86
Grate Area (sq ft / m2)17.65 / 1.6417.34 / 1.6117.34 / 1.6117.60 / 1.6417.60 / 1.64
Evaporative Heating Surface (sq ft / m2)1392 / 129.371256 / 116.731256 / 116.731392 / 129.371284 / 119.33
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1392 / 129.371256 / 116.731256 / 116.731392 / 129.371284 / 119.33
Evaporative Heating Surface/Cylinder Volume220.78177.69177.69196.93181.65
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation22952774277422882816
Same as above plus superheater percentage22952774277422882816
Same as above but substitute firebox area for grate area18,46014,88014,88018,46020,416
Power L144784025441539954496
Power MT342.19271.57297.89302.14331.50

Principal Dimensions by Steve Llanso of Sweat House Media
ClassO/D9aP/D11P/D11aP/D12P/D12a
Locobase ID3487 1149 4152 2828 2829
RailroadPennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)
CountryUSAUSAUSAUSAUSA
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class132146241
Road Numbers
GaugeStdStdStdStdStd
Number Built132146241
BuilderAltoonaAltoonaAltoona
Year18891883188318901889
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 8.50 / 2.59 7.75 / 2.36 7.75 / 2.36 7.75 / 2.36 7.75 / 2.36
Engine Wheelbase (ft / m)23.45 / 7.1522.54 / 6.8722.70 / 6.9222.50 / 6.8622.70 / 6.92
Ratio of driving wheelbase to overall engine wheebase 0.36 0.34 0.34 0.34 0.34
Overall Wheelbase (engine & tender) (ft / m)47.37 / 14.4448.50 / 14.7848.10 / 14.6648.60 / 14.81
Axle Loading (Maximum Weight per Axle) (lbs / kg)31,100 / 14,10738,200 / 17,32738,200 / 17,32736,225 / 16,43136,850 / 16,715
Weight on Drivers (lbs / kg)59,800 / 27,12574,400 / 33,74767,800 / 30,75472,100 / 32,70473,350 / 33,271
Engine Weight (lbs / kg)96,700 / 43,862108,700 / 49,306100,600 / 45,631105,250 / 47,741106,500 / 48,308
Tender Loaded Weight (lbs / kg)73,350 / 33,27156,300 / 25,53756,300 / 25,53756,300 / 25,53769,700 / 31,615
Total Engine and Tender Weight (lbs / kg)170,050 / 77,133165,000 / 74,843156,900 / 71,168161,550 / 73,278176,200 / 79,923
Tender Water Capacity (gals / ML)3600 / 13.642400 / 9.092400 / 9.093000 / 11.363000 / 11.36
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 7.50 / 6.806 / 5.506 / 5.50 7.50 / 6.80 7.50 / 6.80
Minimum weight of rail (calculated) (lb/yd / kg/m)50 / 2562 / 3157 / 28.5060 / 3061 / 30.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)68 / 172762 / 157568 / 172762 / 157568 / 1727
Boiler Pressure (psi / kPa)160 / 11140 / 9.70140 / 9.70160 / 11160 / 11
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x61018.5" x 24" / 470x61018.5" x 24" / 470x61018.5" x 24" / 470x61018.5" x 24" / 470x610
Tractive Effort (lbs / kg)15,552 / 7054.2815,766 / 7151.3514,375 / 6520.4018,018 / 8172.8416,428 / 7451.62
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.85 4.72 4.72 4.00 4.46
Heating Ability
Firebox Area (sq ft / m2)127.60 / 11.86164.40 / 15.28164.40 / 15.28138 / 12.82138 / 12.83
Grate Area (sq ft / m2)17.60 / 1.6434.76 / 3.2334.76 / 3.2333.25 / 3.0933.25 / 3.09
Evaporative Heating Surface (sq ft / m2)1284 / 119.331530 / 142.191530 / 142.191384 / 128.581382 / 128.44
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1284 / 119.331530 / 142.191530 / 142.191384 / 128.581382 / 128.44
Evaporative Heating Surface/Cylinder Volume181.65204.91204.91185.36185.09
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation28164866486653205320
Same as above plus superheater percentage28164866486653205320
Same as above but substitute firebox area for grate area20,41623,01623,01622,08022,080
Power L149314557499845925032
Power MT363.58270.07325.04280.82302.49

Principal Dimensions by Steve Llanso of Sweat House Media
ClassP/D13P/D13a, D13cP/D14P/D14aT/D15
Locobase ID2830 3489 2831 2832 1152
RailroadNorthern Central (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)Pennsylvania (PRR)
CountryUSAUSAUSAUSAUSA
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class21506161
Road Numbers1515
GaugeStdStdStdStdStd
Number Built21506161
BuilderAltoonaAltoonaAltoonaAltoonaAltoona
Year18921892189218941892
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 7.75 / 2.36 7.75 / 2.36 7.75 / 2.36 7.75 / 2.368 / 2.44
Engine Wheelbase (ft / m)22.70 / 6.9222.70 / 6.9222.70 / 6.9222.79 / 6.9523.94 / 7.30
Ratio of driving wheelbase to overall engine wheebase 0.34 0.34 0.34 0.34 0.33
Overall Wheelbase (engine & tender) (ft / m)48.60 / 14.8148.60 / 14.8148.60 / 14.8149.27 / 15.0248.09 / 14.66
Axle Loading (Maximum Weight per Axle) (lbs / kg)37,708 / 17,10437,708 / 17,10442,000 / 19,05143,500 / 19,73148,500 / 21,999
Weight on Drivers (lbs / kg)74,716 / 33,89174,716 / 33,89182,600 / 37,46787,300 / 39,59995,200 / 43,182
Engine Weight (lbs / kg)109,716 / 49,766109,716 / 49,766122,600 / 55,610127,650 / 57,901145,500 / 65,998
Tender Loaded Weight (lbs / kg)69,700 / 31,61569,700 / 31,61569,700 / 31,61570,000 / 31,752
Total Engine and Tender Weight (lbs / kg)179,416 / 81,381179,416 / 81,381192,300 / 87,225197,650 / 89,653
Tender Water Capacity (gals / ML)3000 / 11.363000 / 11.363000 / 11.363000 / 11.363000 / 11.36
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 7.50 / 6.80 7.50 / 6.80 7.50 / 6.80 7.50 / 6.80 7.50 / 6.80
Minimum weight of rail (calculated) (lb/yd / kg/m)62 / 3162 / 3169 / 34.5073 / 36.5079 / 39.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)62 / 157568 / 172778 / 198180 / 203284 / 2134
Boiler Pressure (psi / kPa)160 / 11160 / 11175 / 12.10175 / 12.10205 / 14.10
High Pressure Cylinders (dia x stroke) (in / mm)18.5" x 24" / 470x61018.5" x 24" / 470x61018.5" x 24" / 470x61019" x 24" / 483x61019.5" x 28" / 495x711 (1)
Low Pressure Cylinders (dia x stroke) (in / mm)31" x 28" / 787x711 (1)
Tractive Effort (lbs / kg)18,018 / 8172.8416,428 / 7451.6215,665 / 7105.5316,110 / 7307.3815,825 / 7178.11
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.15 4.55 5.27 5.42 6.02
Heating Ability
Firebox Area (sq ft / m2)137 / 12.36137 / 11.71148 / 13.75148 / 13.75163 / 15.15
Grate Area (sq ft / m2)33.25 / 3.0933.25 / 3.0933.25 / 3.0933.25 / 3.0930 / 2.79
Evaporative Heating Surface (sq ft / m2)1572 / 146.101572 / 146.101583 / 147.121583 / 147.121825 / 169.61
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1572 / 146.101572 / 146.101583 / 147.121583 / 147.121825 / 169.61
Evaporative Heating Surface/Cylinder Volume210.53210.53212.01201.00377.13
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation53205320581958196150
Same as above plus superheater percentage53205320581958196150
Same as above but substitute firebox area for grate area21,92021,92025,90025,90033,415
Power L149985481707868826195
Power MT294.95323.45377.83347.59286.92

Principal Dimensions by Steve Llanso of Sweat House Media
Classunknownunknown
Locobase ID11,176 9519
RailroadPhiladelphia & Columbia (PRR)Pittsburgh, Fort Wayne & Chicago (PRR)
CountryUSAUSA
Whyte4-4-04-4-0
Number in Class4
Road Numbers193-196
GaugeStd4' 9.2""
Number Built4
BuilderLancasterM. Baird & Co
Year18561867
Valve GearStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)5 / 2.13
Engine Wheelbase (ft / m)
Ratio of driving wheelbase to overall engine wheebase
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)46,700 / 21,183
Engine Weight (lbs / kg)73,000 / 33,112
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)39 / 19.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)60 / 152466 / 1676
Boiler Pressure (psi / kPa)130 / 9120 / 8.30
High Pressure Cylinders (dia x stroke) (in / mm)16" x 22" / 406x55916" x 24" / 406x610
Tractive Effort (lbs / kg)10,372 / 4704.679495 / 4306.86
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.92
Heating Ability
Firebox Area (sq ft / m2)83.14 / 7.7386.10 / 8
Grate Area (sq ft / m2)15 / 1.39
Evaporative Heating Surface (sq ft / m2)974 / 90.52831 / 77.23
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)974 / 90.52831 / 77.23
Evaporative Heating Surface/Cylinder Volume190.25148.79
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation1800
Same as above plus superheater percentage1800
Same as above but substitute firebox area for grate area10,80810,332
Power L135292981
Power MT281.45

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