Ferrocarril del Pacifico Alco S6 722 at Sufragio, Sinaloa, Mexico, February 25, 1978. Photographer: Paul Hunnell.
"You know, it just doesn't get much better than this for roster photography. Freshly outshopped from Empalme, a few kilometers north, a turntable, period equipment,
a stunningly beautiful Sonoran/Sinaloan sky, and beautiful desert background. And, a thoroughly excellent photographer!" - Craig Garver
(Craig Garver, Public domain, https://www.flickr.com/photos/digitalrailartist/51809042746/in/dateposted/)
ALCO S-6
Alco SB-8/SSB-9 re-directs here.
The Alco S-6 (specification DL 430) was a diesel-electric switcher locomotive constructed by ALCO of Schenectady, New York; a total of 126 locomotives were built between May 1955 and December 1960. The S-6 was an improved version of the earlier S-5.
Southern Pacific Alco S-6 No 1271 at Newhall, CA, May 1966.
(Drew Jacksich from San Jose, California Republic, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0>, via Wikimedia Commons)
Design
Visually indistinguishable from the S-5, the S-6 used an ALCO 251A or 251B prime mover rated at 900 horsepower (670 kW). The locomotive rode on two-axle AAR trucks, giving a B-B wheel arrangement. ALCO produced a cow-calf variant for the Oliver Iron Mining Company designated SB-8/SSB-9, two sets were produced of this version.
Original owners
| Railroad | Quantity | Road Numbers | Notes |
|---|---|---|---|
| Allied Chemical Company | 1 | 110 | |
| ARMCO Steel | 1 | 1202 | |
| B. Perini & Sons Construction Company | 1 | 101 | to Upper Merion and Plymouth Railroad 101 |
| Belt Railway of Chicago | 1 | 420 | |
| Ferrocarril Chihuahua al Pacífico | 1 | 60 | Renumbered 106 |
| Cia Fundidora de Hierro y Acero | 3 | 1-3 | |
| Ferrocarril del Pacífico | 24 | 701–723 | |
| Ferrocarriles Nacionales de México | 1 | 5300 | |
| Northern Pacific Railway | 1 | 750 | to Burlington Northern Railroad 950 |
| Ohio River Company (ORCo) | 1 | 56 | |
| Republic Steel | 3 | 153, 317, 318 | |
| Secretaria de Comunicaciones de Obras Publicas (SCOP) | 3 | 7133-1, 2, 3 | to Ferrocarril del Sureste (same numbers) |
| Sheffield Steel | 2 | 15, 16 | |
| Southern Pacific Railroad | 70 | 1033–1082, 4634–4645 | renumbered 1200–1257, 1270–1281 |
| South Buffalo Railway | 6 | 40–45 | |
| Tennessee Copper | 1 | 107 | |
| Upper Merion and Plymouth Railroad | 1 | 61 | |
| U.S. Pipe and Foundry | 1 | 38 | |
| Columbia Geneva Steel | 1 | 1 | |
| Western Maryland Railway | 2 | 151, 152 | |
| Ferrocarriles Unidos de Yucatán | 1 | 301 |
Southern Pacific Alco S-6 No. 1085 at San Jose, CA, August 1964.
(Drew Jacksich from San Jose, California Republic, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0>, via Wikimedia Commons)
In popular culture
In Back to the Future Part III, two double headed S-6 locomotives destroyed the DeLorean time machine, when it returned to 1985.
ALCO S-6 Overview
Type and origin
Power type: Diesel
Builder: ALCO
Model: S-6
Build date: May 1955–December 1960
Total produced: 126
Specifications
Configuration:
• AAR: B-B
• UIC: Bo′Bo′
Gauge: 4 ft 8+1⁄2 in (1,435 mm)
Length: 45 ft 5 in (13.84 m)
Width: 10 ft (3.05 m)
Height: 14 ft 8 in (4.47 m)
Loco weight: 230,000 lb (104.3 tonnes)
Fuel capacity: 635 US gal (2,400 L; 529 imp gal)
Lubricant capacity: 140 US gal (530 L; 120 imp gal)
Coolant capacity: 110 US gal (420 L; 92 imp gal)
Sandbox capacity: 26 cu ft (0.74 m3)
Prime mover: Alco 251A or B
RPM range: 375–1000 rpm
Engine type: Four-stroke diesel
Generator: GE GT-533 (or GE GT-584)
Traction motors: 4 × GE 731 (GE 752 optional)
Cylinders Straight: 6
Cylinder size: 9 in × 10+1⁄2 in (229 mm × 267 mm)
Performance figures
Maximum speed: 60 mph (97 km/h)
Power output: 900 hp (670 kW)
Career
Locale: United States, Mexico
See Also:
