Articulated locomotives, popularly known as Mallets, have captivated model railroaders and railroad enthusiasts for nearly 100 years with good reason. The sight and sounds of those monsters of the railroads left an indelible image in the minds of many that is kept alive with current steam restoration projects like Union Pacific “Big Boy” and the N&W class “A” locomotives that still polish the rails for selected events.
Operating demands of the expansive railroad age necessitated the development of articulated locomotives. That design was driven by the need to spread the weight of heavier locomotives over a larger wheelbase to lessen damage to the track and roadway structure and the corresponding requirement to hinge two wheel bases so locomotives could navigate curves and crossovers.
Several basic designs of articulated locomotives were constructed in Europe and the US between 1840 and 1880 but in 1883 French engineer Anatole Mallet invented a revolutionary design where the boiler and firebox were attached to the rear chassis leaving the front chassis to pivot freely beneath the front of the boiler and smokebox. The two rear cylinders took steam directly from the boiler then exhausted it to the two larger front cylinders and then the exhaust steam went up the stack. Belgium received the first Mallet type locomotive but 17 years passed before that design was tested in the US.
The pioneering legacy of the Baltimore & Ohio Railroad (B&O) was reinforced once more in 1904 when they took delivery of the first US Mallet design locomotive from American Locomotive Company. B&O #2400, affectionately nicknamed “Old Maude” was featuring a 0-6-6-0 wheel arrangement and was designed to replace a pair of 2-8-0 locomotives in helper service on mountain grades. Though not duplicated, B&O eventually purchased much larger 0-8-8-0 locomotives for helper service and 2-8-8-0 locomotives for heavy coal train service.
In that early period railroad mechanical officers were divided between those that viewed mallets as pusher locomotives (Erie, Delaware & Hudson, New York Central) and those that viewed them as drag-freight motive power (Chesapeake & Ohio, Norfolk & Western and Virginian) where speed was not critical. Still other operating men looked at Mallets as a way to simply assemble longer trains, reduce rosters of older locomotives and lessen double-heading and the expense of two crews. The popular phrase of those early, slow drag freights among railroad men was “they hung everything on that train but the yard office”. Shippers eventually complained loudly about slow service and railroads retreated a bit from that drag-freight mentality in the prosperous 1920s due to the time-sensitive supply-material needs of the emerging auto industry. (In a sense slow drag-freight, shipper be damned mentality of WWI era forecasted the downside of Precession Scheduled Railroading practice amplified by the notorious Hunter Harrison on CSX in 2017 and later copied by Norfolk Southern and Union Pacific.)
Just as the perception of how to harness that brute power varied, so did the various designs of how to best accomplish that goal. Various attempts included taking two, 2-8-0 locomotives and combining them into one Mallet (B&O), a boiler with a folding mid-section and ball-joint connections (Santa Fe) and the triplex locomotives that featured a 2-8-8-8-2 wheel arrangement (Erie and Virginian). All those attempts however suffered from having fireboxes that were too small to produce adequate steam for monstrous boilers. More unique and ultimately successful were the so-called reverse mallets, the cab-forwards of the Southern Pacific. The might Pennsylvania Railroad fielded a huge 2-8-8-0 locomotive #3700 in 1919 that was so powerful that it pulled out the drawbars (couplers) in freight trains. Although that issue could have been tamed, PRR remained cool toward Mallets favoring simple two-cylinder locomotives until flirting disastrously with duplex-drive locomotives in the 1940s.
By the 1920s more advanced mechanical practice and the research that American Locomotive Company (ALCo) and Lima Locomotive Works produced elevated newer Mallet designs for heavy fast freight service. Alco achieved notoriety with the construction of the UP “Big Boy” in 1942 but the record for constructing the heaviest and most powerful Mallets goes to Lima with the first 30 C&O class H8 Allegheny Locomotives. Two of the classic H8 locomotives survive but no serious discussions or efforts toward restoration for operation have surfaced and most likely never will since one is safely housed in the Henry Ford Museum in Dearborn MI and the other in the B&O Railroad Museum in Baltimore, MD. Although CSX has representation on the Board at the B&O Museum, that carrier has intentionally distanced itself from its rich heritage of steam operation contrasting the commitment at NS and UP, current industry giants that are not ashamed of their past accomplishments in evolving motive power technology and go on to willingly share that with younger generations.
Oddities in Mallet history include the fact that the last domestic steam locomotives Baldwin Locomotives delivered in the US were ten 2-6-6-2 Mallets for the C&O in 1949 that were essentially copies of a design that dated back to the 1920s. The reasoning behind that was C&O needed additional locomotives for branch lines into the coal fields that could not tolerate a larger, more modern and heavier design. The very last locomotive in that order, C&O #1309 is currently undergoing restoration for operation on the Western Maryland Scenic Railway. N&W built the very last domestic Mallets in 1952 when Roanoke Shops completed a batch of class Y6 2-8-8-2 locomotives. Both the N&W and UP kept their fleet of Mallets alive well into 1958.
This story does not stop with demise of steam or nostalgic looks back however. Mallets paved the way for the contemporary, high horsepower, high adhesion diesel-electric locomotives that dominate freight transportation today. For that reason we want to celebrate both the powerful Mallets of the past and the state of the art locomotives of the present in this special promotion. No matter what era you prefer we guarantee that our current selection has something that will enhance your model railroad operation. Steam or diesel alike, all made viable with our Rewards Program and for a Limited Time, 10% off on all locomotives. Just use promo code LOCO10 at checkout!
FAW, MBK, Inc.