Fairbanks Morse Units

In Prospector Volume 24 Number 2, we began a two-part series on the Rio Grande's Fairbanks-Morse locomotives, Part one covering the H10-44 switchers and the H15-44 road switchers. Part two will cover the Train Master tests and the Erie-builts.

The collaboration of author Allen Copeland and member John Tudek have brought us a comprehensive look at these five unique locomotives. John spent several days at the Colorado Railroad Museum combing through the Rio Grande records preserved there bringing the folios, valuation cards and other records for these units. There was not enough room in these issue to include these for every unit so we have placed them on here on the RGM&HS website here:

H10-44 switcher
H15-44 road switchers

Letter J.E. Justus (Fairbanks- Morse) to A.E. Rice (D&RGW Chief Mechanical Officer) Serial numbers for the H10-44 locos

The Fairbanks‑Morse H10‑44 switchers represent a significant chapter in North American railroading. Introduced in 1944 and built until 1950, these locomotives marked FM’s debut in the switcher market. Powered by a six‑cylinder, two‑cycle opposed‑piston engine that started at around 1,000 horsepower—with many later upgraded to 1,200—these units quickly earned a reputation for reliability and versatility. Their unique design, featuring a slanted nose, smooth hood lines, and a distinctive roof visor inspired by Raymond Loewy, helped them stand out visually while proving their worth in demanding yard and short transfer service.

Beyond their technical success, the H10‑44 switchers also symbolize the transformative shift from steam to diesel power. The Prospector article by Allen Copeland (with insights from John Tudek) draws on original records from institutions like the Colorado Railroad Museum to detail the operational history of these locomotives. This research not only sheds light on the role the switchers played for railroads such as the Denver & Rio Grande Western.

The H10-44 Roster

Class DE-72 B-B D/E 40 1000 hp 241,000 241,000 72,286 F-M Model H10-44

Number	Builder c/n	Date	Remarks
120	F-M 10-L-53	4/27/1948	Ret. 1/23/1967. Trade-in to EMD (on SD45 Nos. 5315-5324)
121	F-M 10-L-54	4/27/1948	Ret. 1/23/1967. Trade-in to EMD (on SD45 Nos. 5315-5324
122	F-M 10-L-55	4/27/1948	Ret. 1/19/1968. Sold same day Precision Engineering Co., Mt. Vernon, Ill. Sold 6/1969 St. Louis-San Francisco No. 286. Traded in to GE 8/30/1973.
123	F-M 10-L-58	4/30/1948	Ret. 1/23/1967. Trade-in to EMD (on SD45 Nos. 5315-5324)

All were ordered on F-M order No. LD-37. They were not equipped for multiple unit operation.

Form No. 4-A, the Specification Sheet for locomotive 120, this would have been attach to a folio diagram showing general outline of unit and principal dimensions.showing the outline and general dimensions of the unit. – D&RGW, Colorado Railroad Museum collection

Locomotive Inspection Record provides the details for the 120. – Fairbanks, Morse & Company, Colorado Railroad Museum collection

Valuation Card for locomotive 120 from January 1967, showing all modifications to the unit and that it was traded-in to EMD of GM for trade in credit on new SD45 locomotives on AFE No. 6897. – D&RGW, Colorado Railroad Museum collection

Form No. 4-A, the Specification Sheet for locomotive 121, this would have been attach to a folio diagram showing general outline of unit and principal dimensions.showing the outline and general dimensions of the unit. – D&RGW, Colorado Railroad Museum collection

Each locomotive was inspected at FM and this Locomotive Inspection Record provides the details for the 121. – Fairbanks, Morse & Company, Colorado Railroad Museum collection

Valuation Card for locomotive 121 from January 1967, showing all modifications to the unit and that it was traded-in to EMD of GM for trade in credit on new SD45 locomotives on AFE No. 6897. – D&RGW, Colorado Railroad Museum collection

Form No. 4-A, the Specification Sheet for locomotive #122, this would have been attach to a folio diagram showing general outline of unit and principal dimensions.showing the outline and general dimensions of the unit. – D&RGW, Colorado Railroad Museum collection

Inspection Form -H10-44~1 #122. Each locomotive was inspected at FM – Fairbanks, Morse & Company, Colorado Railroad Museum collection

Valuation Card for locomotive 122 from January 1968, showing all modifications to the unit and that it was SOLD to Precision Engineering Co. of Mt. Vernon, Illinois where it was scrapped on AFE No. 7198. – D&RGW, Colorado Railroad Museum collection

Form No. 4-A, the Specification Sheet for locomotive 123, this would have been attach to a folio diagram showing general outline of unit and principal dimensions.showing the outline and general dimensions of the unit. – D&RGW, Colorado Railroad Museum collection

Each locomotive was inspected at FM and this Locomotive Inspection Record provides the details for the 123. – Fairbanks, Morse & Company, Colorado Railroad Museum collection

Valuation Card for locomotive 123 from January 1968, showing all modifications to the unit and that it was SOLD to Precision Engineering Co. of Mt. Vernon, Illinois where it was scrapped on AFE No. 7198. – D&RGW, Colorado Railroad Museum collection

The Fairbanks‑Morse H15‑44 road switchers represent a distinct evolution from the earlier yard-bound models. Building on a similar robust diesel platform, these locomotives were adapted for road service with design modifications that improved speed and efficiency while retaining the rugged performance that FM was known for. Their engineered balance allowed railroads to reap the benefits of both reliable switching and light road-haul capability—a versatility that set them apart during the critical diesel transition era.

As detailed in the comprehensive Prospector article by Allen Copeland, archival research from the Colorado Railroad Museum and other sources reveals that the H15‑44 units filled a key niche in operational history. Their dual-purpose design not only met the demands of evolving railroad service but also showcased FM’s innovative approach to locomotive development. This summary enriches our understanding of how these road switchers contributed to a period of rapid technological change, making them a fascinating study for both rail historians and enthusiasts.

The H15-44 Roster

Class DE-60 B-B D/E 40 1500 hp 241,000 241,000 60,250 F-M Model H15-44

Number	Builder c/n	Date	Remarks
150	F-M 15-L-3	1/31/1948	Ret. 4/8/1966. Sold same date Precision Engineering Co.
151	F-M 15-L-4	4/27/1948	Ret. 4/8/1966. Sold same date Precision Engineering Co.
152	F-M 15-L-5	4/27/1948	Ret. 4/8/1966. Sold same date Precision Engineering Co.

All were ordered on F-M order No. LD-36. They were not equipped for multiple unit operation. Nos. 151 and 152 equipped with electrical connections for operation with slug No. 25 at Grand Junction.