The Lone Survivor
The very first cab-forward locomotive was delivered to the Southern Pacific Railroad in 1910. While the configuration certainly improved visibility for the crew, the main advantage of the cab relocation was in preventing the crew from becoming asphyxiated by the exhaust fumes while going through long tunnels and snow sheds. The cab-forwards were primarily used in the Sierra Nevada range, but also saw use in other parts of California on the SP lines. Baldwin would eventually build 256 of the cab-forwards for the Southern Pacific. SP4294 was one of the final cab-forwards and one of the final steam engines acquired by Southern Pacific (part of the AC-12 series). While articulated, SP4294 was not a true Mallet.
Of the 256 Cab Forward locomotives Baldwin built for the Southern Pacific Railroad, SP4294 is the lone survivor. Today SP4294 resides in Sacramento at the California State Railroad Museum.
Since the firebox was located at the front of the engine, the cab-forwards were oil burners. The oil reservoir in the tender was air tight and would be slightly pressurized in order to assure the flow of oil on uphill grades.
Due to the high stack velocities of the large cab-forwards, stack splitters were installed to prevent the roofing from being blown off of snow sheds.
The Monkey Deck
Another feature of the SP cab-forwards was the platform at the rear of the engine, just before the tender. Due to it's location, this platform would not be a pleasant place to hitch a ride, and as a result was referred to as the Monkey Deck.
Tractive Effort: 124,300 lbs
Two XL Power Functions motors are used, one to power each set of drivers. The battery box and IR sensor are also contained in the body of the locomotive.
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Edited by Cooper, 02 October 2009 - 04:45 PM.