The first "Santa Fe" type locomotives on the Southern Pacific Railroad were ten delivered by the American Locomotive Company in 1917. This group was designated as Class F-1 with road numbers 3601 through 3610 assigned. These locomotives had 63" diameter drivers, 27.5" x 32" cylinders, a 200 psi boiler pressure, they exerted 65,301 pounds of tractive effort and each weighed 352,000 pounds. ALCO also delivered one more 2-10-2 in 1918. This locomotive was similar to the Class F-1s but it had 57" diameter drivers and 26" x 32" cylinders. It was given road number 3600 and classified as Class F-2 until it was rebuilt to the F-1 specifications in 1920 and reclassified as a Class F-1.

The Texas & New Orleans received twelve of the Class F-1 locomotives in 1918. They were given road numbers 970 through 981.

In 1919, the Baldwin Locomotive Works delivered forty-one of the Class F-1 locomotives which were assigned road numbers 3611 through 3651 and ALCO delivered only one which was given road number 3652.

The Lima Locomotive Works received one order from the SP for fifteen of the 2-10-2s. This group was designated as Class F-3 and it was assigned numbers 3653 through 3667. They had 63" diameter drivers, 29.5" x 32" cylinders, a 200 psi boiler pressure, they exerted 75,145 pounds of tractive effort and each weighed 385,000 pounds.

In the Whyte notation for the classification of steam locomotives the 2-10-0 wheel arrangement was named "Decapod", and this name was sometimes applied to locomotives of 0-10-0 "Ten-Coupled" arrangement. The Southern Pacific did not have any of the 0-10-0 or the 2-10-0 locomotives and when the 2-10-2s arrived it was difficult for enginemen to refer to them as "Santa-Fes" so they called them "Decks" for deca (ten).

Baldwin received an order for fifty 2-10-2s which it delivered in 1922. These locomotives were designated as Class F-4 and were given road numbers 3668 through 3717. They had 63" diameter drivers, 29.5" x 32" cylinders, a 200 psi boiler pressure, they exerted 75,145 pounds of tractive effort and each weighed 398,000 pounds.

Another order was given to Baldwin for 52 more of the 2-10-2s. During 1923 and 1824 it delivered fifty-one of them which the SP designated as Class F-5 with road numbers 3718 through 3768 assigned. These locomotives had 63" diameter drivers, 29.5" x 32" cylinders, a 200 psi boiler pressure, they exerted 75,145 pounds of tractive effort and each weighed 397,900 pounds. The 52nd locomotive was number 3769 delivered in 1924. It was fitted with Uniflow valves on delivery and Classified as Class F-6. The valve gear was changed to Walschaert valve gear in 1925. In 1931 the locomotive was fitted with Caprotti valve gear, which was removed when number 3769 was rebuilt and reclassified as a standard Class F-5 in 1937.

There are two surviving SP 2-10-2 "Santa Fe" type locomotives. One is number 3651. Number 3651 was transferred to the T&NO and was renumbered as 982. It is on display at TRPA Union Station, Minute Maid Baseball Park in Houston, Texas. The other is T&NO number 975, which is on display at the Illinois Railway Museum in Union, IL.

Class F-1 (Locobase 3292)

See Railway Age, 2 July 1921 and DeGolyer, Vol 56, pp. 349+. Baldwin works numbers were 51602-51603 in March; 51672-51674, 51677, 51696-51697 in April; 51763, 51792-51796, 51819-51821, 51831-51837 in May; 51862-51864, 51900-51903, 51932-51935, 51948-51951 in June;52010-52011, 52012, 52051-52053 in July.

The Espee first procured 2-10-2s with this batch from Brooks and Baldwin. Known as "Decks" (Decapods) on the Southern Pacific, the F-1s represented a step up in power over the Mikados and Consolidations that were already in service. They were followed a few years later by the F-3 line, which had a larger cylinder and significantly large heating surface.

RA's account showed a 273,000-lb (123,831 kg) weight on the drivers. The addition of a Worthington 4S feedwater heater contributed 9,000 lb (4,082 kg) of weight.

F-1s were apparently quite satisfactory, even though they were less powerful than the later F-3s, and operated on the lines until 1952-1958.

Class F-3/F-4 (Locobase 3291)

Data from "Heavy Locomotives for the Southern Pacific", Railway Age, Vol 71, No1 (2 July 1921), pp. 15-17 and SP 7 - 1951 Locomotive Diagrams supplied ni May 2005 by Allen Stanley from his extensive collection.. See also the detailed article "Powerful Locomotives for the Southern Pacific Lines", Railway Journal, Vol 28 (June 1922), pp 11-12. Works numbers were (F-3) 54312-54313, 54381-54385, 54502-54509 in January 1921 and (F-4) 55233-55244, 55261-55272 in January 1921; 55293, 55304-55312 in March; 55326-55338 in April; 55377-55379. in May.

The first in a series of uprated Santa Fes that included the 50 F-4s brought west in a single train called the Prosperity Special in 1922 and 51 F-5s delivered in 1923-1924. All were Baldwin built and all had very similar dimensions. All were delivered with 63 1/2" diameter drivers. Known as "Decks" (Decapods) on the Southern Pacific.

Compared to the later F-5, the F-3s had a slightly lower superheat percentage and as is usual with a series, started off with the lowest weights. RA reported that the new Santa Fes were put in service in the Los Angeles-Bakersfield section, a 171-mile run with 2.2-2.37% grade westbound and 2.23-2.54% grades eastbound. Tonnage ratings for the F-3s (and presumably the F-4 and F-5 engines) came to 1,005 tons westbound, 875 tons eastbound.

Locobase 86 shows a later set of firebox and superheater areas that appears to have been standard for all of the Decks from this era. F-3s served until retirement in 1952-1958; F-4s had a similar career and were retired in 1951-1958.

Class F-5 (Locobase 86)

Data from 1930 Locomotive Cyclopedia and SP 7 - 1951 Locomotive Diagrams supplied ni May 2005 by Allen Stanley from his extensive collection. Works numbers were 57003 in October 1923; 57357-57363 in October; 57429-57433, 57441, 57472-57491 in November; 57608-57609 in January 1924; 57620-57629, 57650-57651 in February; 57660-57662 in March.

Boiler had feedwater heater. The last in a run of Santa Fes that included the F-3 and the 50 F-4s brought west in a single train called the Prosperity Special in 1922 (see Locobase 3291). The original 1930 table showed a firebox heating surface of 381 sq ft, which is a minor difference from the SP diagram, and a superheater area of 1,381 sq ft, which was a much greater difference.

Locobase uses the SP measurements on the grounds that that was what the railroad would use to assess relative capacity.

Most of the F-5s went to the Texas & New Orleans lines, where they worked until retirement in 1949-1956.