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The RSD-17: The "Empress of Agincourt"

Published: August 16, 2024

By: Adam Burns

The RSD-17 is a unique model within the Montreal Locomotive Works (MLW) catalog and was based from Alco's RSD-15 in the United States.

Introduced in May, 1957, demonstrator #7007 - the only unit produced - was designed primarily for heavy freight service, especially on railways requiring robust power and enhanced tractive effort.

Unfortunately, while Alco designs were well-regarded in Canada, MLW could find no buyers for the RSD-17.  The demonstrator tested on Canadian Pacific, Canadian National, and Pacific Great Eastern before it was purchased by CP and numbered #8921.

Given the nickname "Empress of Agincourt," it was generally well-regarded at CP and was typically assigned to transfer service out of Agincourt Yard in Toronto.

While the RSD-17 did not achieve widespread adoption, its impact was significant as it played a crucial role in helping railroads transition to more powerful and efficient diesel-electric models.  MLW, and successor Bombardier, continued producing locomotives at the Montreal plant into the 1980s.

CP Rail (Canadian Pacific) RSD17 #8921, the 'Empress of Agincourt,' crosses the diamonds on its way to Lambton Yard in Toronto on September 28, 1978. The unique unit worked Toronto area transfers out of Agincourt Yard and later received a chop nose. Doug Kroll photo.

Development

In 1956 Alco continued to refine its catalog by offering more poweful road-switcher models.  One interesting design was the RSD-15, known colloquially by railfans as the "Alligator" due to its long, low hood profile.

The burly locomotive boasted C-C trucks and was designed primarily for heavy freight service.  Its six powered axles and dynamic braking made it especially effective on rugged and mountainous terrains where traction was paramount. 

Despite its powerful performance, the Alligator faced stiff competition from similar models produced by Electro-Motive; only 75 units were produced and sold to a handful of railroads, including the Santa Fe, Pennsylvania Railroad, and Southern Pacific among others.

Today, the RSD-15 remains a favorite among rail enthusiasts and historians, with several preserved units displayed in museums or used in heritage rail operations. Its robust design and distinctive appearance continue to capture the imaginations of those who appreciate mid-20th-century diesel locomotives.

At its core, both the RSD-15 and RSD-17 were powered by the Alco's 251B prime mover, a V-12 design delivering 2,400 horsepower.  Despite the builder's struggle with the earlier 244, the 251 is generally well regarded as a rugged and reliable platform.

The RSD-17 differs only slightly from its RSD-15 counterpart.  Outwardly it is most easily recongizable by its lack of corner notches along the long hoods, designed to provide access to the sandbox fillers.

Reception

In his book, "The Diesel Builders Volume Two: American Locomotive Company and Montreal Locomotive Works," author John Kirkland notes MLW produced demonstrator #7007 in May 1957 (construction number 81603). 

It was painted in Canadian Pacific colors and used by the railroad until December of that year.  Afterwards, it was transferred to Canadian National and given #3899, demonstrating there until March, 1958.

The following month it tested on Pacific Great Eastern as #624 where it remained until October, 1958.  The unit subsequently returned to MLW before being purchased by CP in September, 1959 (numbered 8921) during a time when the railroad was after greater horsepower and tractive effort.

Specifications

Legacy

Interestingly, its acquisition of the RSD-17 coincided with CP also purchasing 21 new H24-66 "Train Masters" from Fairbanks-Morse/Canadian Locomotive Company.

During its time on CP's roster #8921 generally worked in transfer service out of Agincourt Yard. In 1988, CP rebuilt the locomotive with a chopped nose and it remained in service until May, 1995 when it was finally retired.

It subsequently spent time in the St. Luc deadline for nearly two years before its donation to the Elgin County Railway Museum in January, 1997 where it resides today.

The RSD-17 remains a point of interest for rail enthusiasts and historians. Its robust design and operational history make it a notable example of mid-20th-century diesel technology. 

In summary, this rugged platform stands as a symbol of industrial strength and technological progression, marking a significant chapter in the history of Canadian and North American railroading.