Southern Pacific Railroad's AC-5 class of steam locomotives was the railroad's second class of 4-8-8-2 cab forward locomotives. They were built between July and September 1929 and placed in service soon after construction. The AC-5 class was only slightly larger than the AC-4 class.

This article relies largely or entirely on a single source. (July 2016)

Southern Pacific class AC-5
SP 4116 on freight passing Berkeley bound for Oakland (Calif.).
Type and origin Power type Steam Builder Baldwin Locomotive Works Serial number 60866–60869, 60884–60889, 60952–60957 Build date July–September 1929 Total produced 16
Specifications Configuration: ​  • Whyte 4-8-8-2 Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Driver dia. 63 in (1.600 m) Adhesive weight 482,500 lb (218,900 kg; 218.9 t) Loco weight 622,600 lb (282,400 kg; 282.4 t) Boiler pressure 235 psi (1.62 MPa) Feedwater heater 41⁄4-BL Worthington Cylinder size 24 in × 32 in (610 mm × 813 mm) (bore × stroke)
Performance figures Tractive effort 116,900 lbf (520 kN)
Career Operators Southern Pacific Railroad Class AC-5 Numbers 4110–4125 First run August 16, 1929 Retired 1955 Disposition All scrapped

The first locomotive of this class, number 4110, holds the dubious honor of being the first 4-8-8-2 cab forward locomotive to be scrapped when it befell this fate on February 3, 1953, at the railroad's Sacramento, California, shops. The rest of the class were removed from service and scrapped by mid-1955. None of this class was preserved.

References

• Diebert, Timothy S. & Strapac, Joseph A. (1987). Southern Pacific Company Steam Locomotive Conpendium. Shade Tree Books. ISBN 0-930742-12-5.