Southern Pacific class AC-11

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Southern Pacific class AC-11
SOUTHERN PACIFIC CAB FORWARD CLASS AC-11 4-8-8-2 ARTICULATED OIL BURNING LOCO DESIGN ENGINE NUMBER 4247 SOUTHBOUND BETWEEN SAGE HEN AND MADELINE, CALIFORNIA NEAR THE MODOC NATIONAL FOREST IN 1956.jpg
Type and origin
Power typeSteam
Builder Baldwin Locomotive Works
Serial number64677 64706
Build dateNovember 1942 April 1943
Specifications
Configuration:
   Whyte 4-8-8-2
Gauge 4 ft 8+12 in (1,435 mm) standard gauge
Driver dia.63 in (1,600 mm)
Adhesive weight 531,700 lb (241,200 kg; 241.2 t)
Loco weight657,900 lb (298,400 kg; 298.4 t)
Boiler pressure250 psi (1.7 MPa)
Feedwater heater 6SA Worthington
Cylinder size 24 in × 32 in (610 mm × 813 mm) (bore × stroke)
Performance figures
Tractive effort 124,300 lbf (553 kN)
Career
Operators Southern Pacific Railroad
Class AC-11
Numbers4245 4274
First runNovember 24, 1942
Retired1954 1958
Dispositionall scrapped

Southern Pacific Railroad's AC-11 class of cab forward steam locomotives was the seventh class of 4-8-8-2 locomotives ordered by Southern Pacific (SP) from Baldwin Locomotive Works; [1] SP was so pleased with the AC-10 class built a year earlier that the railroad began placing orders for AC-11s while the AC-10s were still being built and delivered. They were built between November 1942 and April 1943, closely resembling the AC-10s.

The first AC-11, number 4245, entered service on November 24, 1942, and the last, 4274, on May 9, 1943. SP used these locomotives for between 12 and 15 years, with the last retirements from this class occurring on September 24, 1958. Shortly after their retirement, the AC-11s were scrapped, with the last, number 4274, in April of 1959. [2] [3] [4]

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<span class="mw-page-title-main">Milwaukee Road class F7</span> Class of 6 streamlined 4-6-4 steam locomotives

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<span class="mw-page-title-main">Southern Pacific class AC-8</span>

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References

  1. Ransome-Wallis (2013) , p. 323
  2. Scribbins (1997) , p. 93
  3. Boyd (1992) , p. 3
  4. Yenne (1994) , p. 98

Further reading