Trains... Choo Choo, not the dirty kind.

[xoxoxoBruce]

Another cool steam engine, the last one Union Pacific bought. It was converted from coal to oil, demoted from passenger to freight service, used as an experimental ice and snow melter, then used for PR and special requests. It's still in service for UP, and their last Steam Engine on the books.

The Union Pacific 844 is the last steam engine the company built, and it represented the epitome of steam locomotive technology. The 844 rolled out of American Locomotive Company’s (Alco) factory in December 1944. It was the result of seven years of development on UP’s new 800-series and focused heavily on efficiency and speed to combat the new diesel-electric locomotives that were on the rise with their unrelenting fuel economy and reduced downtime. The bed of the firebox and boiler were cast with the chassis as one piece instead of building the locomotive on a riveted frame—much like the difference between a stiff supercar monocoque and a floppy pickup ladder frame. This not only strengthened the 844 as a whole but also reduced its weight significantly, because portions of the drive cylinders and valves, various air channels for the firebox, and the cab floor were integral to the chassis.
This was important, as the 800-series was built to hustle passengers all throughout the Midwest, anywhere from Chicago to Los Angeles, at speeds up to 110 mph. Think about that for a second—just the engine and tender of the 844 weigh almost 1-million pounds (454 tons) along with the added weight of the passenger cars behind it.

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