Class 151 - superheated (Locobase 7114)

Data from RF&P 1937 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Locobase 7113 shows the original configuration of the first RF & P Pacifics. In the 1920s, a few were substantially made over. Cylinder diameter grew by an inch, 24 flues holding a useful amount of superheater area took the place of 130 tubes and the firebox heating surface grew with the addition of 53 sq ft of thermic syphons.

This class left service over a 17-year period beginning in 1929.

Class 201 - superheated (Locobase 7112)

Data from a RF&P 1937 Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

The first of the many classes of Pacifics used by this passenger bridge road, the 80s (Locobase 5694), now renumbered in the 201 series, were taken in hand and superheated in 1921. The new arrangement included 29 sq ft of arch tubes in the firebox and a tube-flue distribution that retained virtually all of the evaporative heating surface while adding a useful percentage of superheater elements.

Class 264 (Locobase 163)

Data from RF&P 1937 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection. Also, see reproduction of 1913 Alco Bulletin 1016 on Richard Leonard's http://www.railarchive.net/alcopacifics/index.html (accessed 16 June 2006).

Light Pacific built with superheaters. As delivered, they had 22"-diameter cylinders and 190 sq ft of firebox heating surface. Compared to most North American Pacifics then or later, this design had quite a lot of evaporative heating surface for the cylinders it fed.

A later updating enlarged the direct heating area by including 29 sq ft of arch tubes and 62 sq ft of thermic syphons in the firebox heating surface. The RF & P also increased cylinder diameter by 1".

Class 301 (Locobase 3310)

This Locobase entry was first recorded as one of the locomotives to which James Partington, Estimating Engineer for Alco, compared his company's #50000 in a 5 November 1921 Railway Age article. Annoyingly, he chose not to identify any of these rivals.

Data from a RF&P 1937 Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive collection suggests that this is Alco's version of an 12-locomotive class that was produced for the RF & P from 1918 to 1925. They were essentially repeats of the earlier 401 (Locobase 1390), but with much taller drivers. Thus, although they resemble the USRA engines in some particulars, this group of locomotives were independently procured.

As built, the firebox heating surface amounted to 259.6 sq ft, of which 25.6 sq ft was arch tubes. Some time later, the railroad revised the firebox layout, deleting some of the arch tubes (leaving 16 sq ft) and adding 75 sq ft of thermic syphons.

Alco delivered 301-306 under order R-265 in 1918 and followed with 2 more under order R-293 in 1920. Baldwin completed the class with 4 in 1925

Class 301 (Locobase 6679)

Data from RF&P 1937 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Although they resemble the USRA engines in some particulars, this group of locomotives were independently procured. Alco delivered 301-305 in 1918, 306-308 in 1920, and Baldwin finished with 4 -- 309-312 -- in 1924. The firebox heating surface included 16 sq ft of arch tubes and 75 sq ft of thermic syphons.

Class 325 (Locobase 164)

Data from tables in 1930 Locomotive Cyclopedia. Works numbers were 59691-59694 in November 1926.

Other than the Wootten-firebox engines of the anthracite lines, this class had one of the largest grates of all North American Pacifics. Boiler pressure later raised to 225 psi and TE increased to 52,050 lb. Fitted with mechanical stokers. Later (1947) operated by the Chesapeake & Ohio as class F-20 and renumbered 486-489. The first two were scrapped in May 1952, the last two in November 1952.

Class 401 (Locobase 1390)

Data from RF&P 1916 and 1937 Locomotive Diagram books supplied in May 2005 by Allen Stanley from his extensive collection.

Passenger Pacifics later rebuilt with cast trailing trucks and Elesco feedwater heaters. Ran until 1950.

Data from table in July 1916 Railway Mechanical Engineer (RME) is very slightly different only because it includes 29.2 sq ft of arch tubes in the firebox heating surface.

RME's January 1916 article on the design notes that the Richmond, Fredericksburg & Potomac service on which these engines operated ran at an average of 36-42 mph with 6 stops pulling very heavy trains.

RME notes the class's 14" "Jack Wilson" balanced slide valves. When this class was later updated, the firebox heating surface increased to 316.2 sq ft, to which arch tubes contributed 15.2 sq ft and thermic syphons 70 sq ft.

Class 51 /251 (Locobase 1389)

Data from RF&P 1937 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Light Pacific built with superheaters. These were delivered to the RF & P's subsidiary Washington Southern at the same time as the Alco-Richmond engines (Locobase 163) but were lighter. As a result, they were slippery on the rails.

Class 56 / 256 (Locobase 6678)

Data from RF&P 1916 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Built for the Washington Southern at about the same time only a few years after Baldwin built Pacifics for the RF & P (Locobase 5694) , these engines differed primarily in the type of valve gear. They were later superheated along the same lines as the 201 class.

Class 60 / 151 (Locobase 7113)

Data from RF&P 1916 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

These were the first Pacifics on the RF & P; 10 were built by Baldwin for the Washington Southern in 1904, while the other 5, appropriately enough, were supplied to the RF & P by Alco's Richmond works a year later. Virtually identical to the Harriman Light Pacific design then being delivered to the Southern Pacific (Locobase 4407) and Union Pacific (Locobase 4408), the design was relatively small even at that early date.

A few of the class were later superheated; see Locobase 7114.

Class 80 / 201 (Locobase 5694)

Data from June 1908 table in American Engineer and Railroad Journal. Works numbers were 31278-31279, 31349, 31359, 31386, and 31416 in July 1907.

These were delivered with slide valves enjoying a 6" travel. One notable ratio is the relatively small firebox heating surface. As these Pacifics operated for several decades (retirements in a wide span from 1937 to 1950), it's not surprising that they were later superheated. See Locobase 7112.