| Burlington Northern Railroad class ARS-3 4056 at Cicero, Illinois on an unknown day in September 1980, photo by Chuck Zeiler. Built in January 1952 as Spokane Portland & Seattle 71 (c/n 79594), it became BN 4056 and was retired in April 1980. This locomotive shows evidence of a water-cooled turbocharger. Beginning in 1953, the trouble prone GE RD-1 air-cooled turbocharger (which GE developed during WWII for P38 aircraft) was replaced by a water-cooled GE RD-3 turbocharger, and in 1954 by Alco's own design, the Model 510. The water-cooled turbocharger was mounted with the cylindrical casing facing the free end of the prime mover. The RD-1 was mounted oriented lengthwise. The external difference was in the exhaust stack. The air cooled turbo stack was oriented lengthwise to the hood, the water-cooled turbo stack was mounted crosswise to the hood, as seen here. Many RS3's were retrofitted with the water cooled turbocharger during their operational lives. The white powder on the roof and running boards is ash from the Mount Saint Helen's eruption. This locomotive was retired in Washington and happened to be in the neighborhood during the eruption, then was shipped east dead for final disposition. |