The Rhode Island Locomotive Works built three 4-6-2 cross-compond locomotives
in 1893 and delivered them to the Chicago, Milwaukee & St. Paul Railroad.
The CM&St.P was not satisfied with the perfomance of these locomotive and
returned them to the builder. They were rebuilt as simple locomotives and
purchased for passenger servce on the SF&W Railway. The Atlantic Coast Line
acquired the three locomotives in 1902 and assigned them road numbers 287
through 289 and designated them as Class J. These locomotives had 19x26
cyinders, 72" drivers, a 165 psi boiler pressure, exerted 20,000 lbs of
tractive effort and each weighed 139,000 pounds. In 1912,the ACL rebuilt
the Class J locomotives into 4-6-0s, renumbered them 1287 through 1289
and designated them as Class K-13.
The Atlantic Coast Line took delivery of 15 "Pacific" type locomotives,
in 1911, from the Baldwin Locomotive Works. these locomotives were given
road numbers 260 through 274 and were designated as Class P. They had 73"
diameter driver and were designed to be main line passenger motive power.
As originally built they used saturated steam, had D-slide valves,
Walschaert valve gear, 22x28 cylinders and a 185 psi boiler pressure.
They exerted 29,600 lbs of tractive effort and each weighed 220,850 pounds.
Later these "Pacifics" were rebuilt with superheaters and the designation
was changed to P-S.
Twelve more "Pacifics", intended for passenger service, arrived from Baldwin
in 1912 and were assigned road numbers 275 through 286 and designated
as Class P-1. These locomotives had superheaters and were similar to
the Class P-S locomotives. They each weighed 225,000 lbs and with 22x28
cylinders, 73" drivers and a boiler pressure of 200 psi exerted 31,600
lbs of tractive effort.
In 1913, the ACL received eleven 4-6-2 locomotives that were designed
and intented for freight service and to also be used to pull high speed
passenger trains. They were designated as Class P-2 and deivered with
road numbers 287 through 297. Later to distiquish them from the passenger
"Pacifics" they were renumbered 400 through 410. These freight haulers
had 22x28 cylinders, 64" drivers, a 200 psi boiler pressure, exerted 36,000
lbs of tractve effort and each weighed 225,900 pounds.
The Class P-2 locomotives did not do well as dual purpose locomotives
and the ACL ordered yet another design and in 1914 it took delivery of 45
dual purpose "Pacifics" from Baldwin. The group was desinated as Class
P-3 and assigned road numbers 411 through 455. The P-3 locomotives had
22x28 cylinders, 69" drivers, a 200 psi boiler pressure, exerted 33,400
lbs of tractive effort and each weighed 226,800 pounds. They were very
sucessful as dual purpose locomotives and 27 similar ones were delivered
by Baldwin between 1916 and 1918. This group designated Class P-4 was
given road numbers 456 through 482. They had 23x28 cylinders and each
weighed about 17,000 pounds more than the Class P-3 locomotives.
Shortly after the close of World War I, the ACL took delivery of 70 USRA
"Pacifics" which were built by the American Locomotive Company. They were
designated as Class P-5A and assigned road numbers 1500 through 1569. These
locomotives had 25x28 cylinders, 73" drivers, a 200 psi boiler pressure,
exerted 40,750 lbs of tractive effort and each weighred 278,000 pounds.
The Class P-5A locomotives were very fast for their time and became the
standard main line passenger locomotive, but they also did well in freight
Needing more motive power the ACL and the Baldwin mechanical engineers
designed a dual purpose "Pacific" to take over freight service. Between
1922 and 1926 Baldwin built 165 of these main line locomotives. They were
designated as Class P-5B and assigned road numbers 1600 through 1764.
The Class P-5A locomotives had 25x28 cylinders, 69" drivers, a 210 psi
boiler pressure, exerted 45,275 lbs of tractive effort and each weighed
bout 285,000 pounds.
In 1946, the ACL received 13 "Pacific" type locomotives when it merger one of
its holdings, the Atlanta, Biringham & Coast Railroad into its operations.
The AB&C had a fleet of locomotives that were mostly purchased second-hand
from other railroads. Eleven of these locomotives were originally owned by
the Florida East Coast Railroad and were built by The American Locomotive
Company. On the ACL they were designated as Class AJ-1 and given road
numbers in the 7000 series. Another two, former Great Northern Railroad
and Lima Locomotive Works built locomotives, were deignated as Class AJ-2
on the ACL and assigned road numbers 7153 and 7175.
All of the ACL "Pacifics" were retired and scrapped in the early 1950s
except for Number 1504. This locomotive was placed on exhibit at the
Convention Center in Jacksonville, FL where it can be seen today.
Class P (Locobase 7673)
Data from ACL 4 - 1942 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. Works numbers were 36866-36869, 36877-36880, 36893-36896, 36960-36962 in September 1911.
These were the first ACL Pacifics and the last to be delivered with saturated boilers (The first 10 used Walschaert radial valve gear while the last 5 had Baker gear (by Pilliod). Later ACL 4-6-2s had shorter boiler tubes.
Some were later superheated; see Locobase 7674.
Class P - superheated (Locobase 7674)
Data from ACL 4 - 1942 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection.
When compared to the superheated P-1-S delivered a year later (Locobase 7681), the pressure vessel in the only set of Pacifics it had purchased with saturated boilers (Locobase 7673) was quite a bit larger. As a result, superheating the design actually added overall heating surface area to the boiler. Moreover, unlike many retrofits that took the opportunity of superheating to reduce boiler pressure, the ACL maintained its P-class engines at their original settings. The result was a powerful express passenger engine.
Class P-1 (Locobase 7681)
Data from DeGolyer, Volume 41, p. 236. Works numbers were 38240-38245, 38335-38338, 38349-38350 in September 1912.
P-1s were delivered by Baldwin with superheaters, becoming the first of the line's Pacifics to have that valuable addition, and 14" diameter piston valves. Arch tubes contributed 29.9 sq ft (2.78 sq m) to the firebox heating surface.
They were passenger engines as opposed to the mixed-traffic 4-6-2s the ACL would soon purchase. Although some of the grades briefly pitched up at 6%, maximum main-line curvature was no more than 3 degrees and the rails weighed in at a relatively hefty 85 lb/yard (42.5 kg/metre).
Most of the class was scrapped in November 1939. Only 3 were scrapped after 7 December 1941, the last to go being the class leader 275 in December 1944.
Class P-2 (Locobase 7669)
Data from ACL 12 - 1954 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. Works numbers were 40119-40129 in July 1913.
This was the third class of Pacifics to run on the ACL and the variant designed to work freight trains. As with most other such designs, the ACL found them less satisfactory than other arrangements. A good factor of adhesion and a relatively large boiler probably accounted for their surviving to the end of steam.
Class P-3 (Locobase 7670)
Data from ACL 12 - 1954 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. See also DeGolyer, Vol 51, pp. 195+ and Vol 59, pp. 29. Works numbers were
March 41252-41258, 41274-41291
November 42652-42657, 42667-42670
October 44260-44264, 44308-44312
Taking the grate of the P-2 (Locobase 7669) as is, and trimming the boiler tubes and flues by two feet (making room for a combustion chamber whose 34 sq ft (3.16 sq m) contributed to the direct heating surface), reducing the size of the firebox slightly but retaining the 30 sq ft (2.79 sq m) of arch tubes and including , then carrying it on 69" drivers, Baldwin came up with a successful mixed-traffic Pacific that served throughout the system. The firebox also had five 2" "combustion tubes" in each side of the firebox under the brick arch
Like the P-2s, the P-3s had relatively generous 14"-diameter piston valves.
Except for 416 (November 1947), 451-452 (May 1949), 415 (October 1949) and class leader 411 (which exploded February 1950), the class went to the scrapyards in the early 1950s.
Class P-4 (Locobase 7672)
Data from ACL 12 - 1954 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Raildata collection. See also DeGolyer, Vol 59, pp. 42+. Works numbers were
August 46065, 46111, 46128, 46169; September 46273-46274
January 47730-47731, 47798-47799; February 47864-47865, 47918-47919, 47963; March 48076, 48145; April 48267, 48402; June 48905-48906, 48993, 49074; July 49232-49233, 49302.
P-4s were enlarged P-3s (Locobase 7670) with more tubes and flues, a larger grate, and greater cylinder volume due to a 1" (25.4 mm) increase in diameter. Baldwin delivered seven in 1917 and the other twenty in 1918.
Like the earlier ACL Atlantics, this class had relatively generous 14" (356 mm) diameter piston valves. The last 8 -- 475-482 -- had 18-ft 2-in (5.54 m) tubes that reduced heating surface areas slightly. Firebox heating surface included 36 sq ft (3.35 sq m) of combustion chamber and 30 sq ft (2.8 sq m) of "firebrick tubes".
Like most of the ACL's Pacifics, this class served the railroad for over 3 decades. The first two to be scrapped -- 464 and 471 -- went in October 1949. Disposals continued over the next two-and-a-half years and culminated in a final block of 11 in March 1952.
Class P-5-A (Locobase 1417)
Data from 1946 ACL locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Raildata collection. Richmond works numbers 59310-59319 in March 1919, 61063-61069 in May. ,
Brooks delivered its contribution (works numbers 61248-61275) in August 1919.
Richmond finished off the order with 62069-62093 in 1920.
This was the "light" Pacific design standardized by the government-run USRA created in World War I and built by Baldwin and Alco. Alco-Brooks and Alco-Richmond delivered these to the ACL.
Slightly modified versions were built as the P-5-B, which see.
Class P-5-B (Locobase 448)
Data from DeGolyer, Vol 68, pp. 181+ and Vol 75, pp. 1+. See also ACL 3 - 1946 Locomotive Diagrams supplied in May 2005 by Allen Stanley.
Works numbers were:
March 56292-56304, 56374-56377
April 56378, 56404-56406, 56453
November 57425-57428, 57438, 57443-57444, 57492-57506
June 57813-57814, 57843-57849, 58492-58494, 58498
July 57878-57884, 57902-57905
July 58516-58527, 58564-58566
January 58931-58935, 58977-58991
Firebox had combustion chamber contributing 44 sq ft (4.1 sq m) of heating surface and a 27 sq ft (2.5 sq m). Almost identical to USRA light Pacific design except for smaller driving wheels and slightly less tube and flue area. Fourteen-inch (356 mm) piston valves supplied the cylinders with steam. Also fitted with Ragonnet power reverse gear.
165 built by Baldwin in 1922-1926 as dual-service locomotives. J Parker Lamb (in Perfecting the American Steam Locomotive, 2003) says that this dual-purpose use was unique among US Pacific operators. The reason lies with the ACL's type of freight traffic -- typically lightweight agricultural products. Like the New York Central, moreover, much of the ACL consisted of water-level running.
Retired in 1950-1953.