FA/FB Diesel Locomotive

Prototype Information

ALCO produced the FA and FB series locomotives between 1946 and 1956 to compete with EMD’s successful F-unit. These cab units featured a distinctive, rugged nose designed by Ray Patten. The FA served as the lead unit with a cab, while the FB was a cabless booster unit. Together, they provided heavy-duty freight power for major railroads like the Pennsylvania, New York Central, and Erie.

The early FA-1 and FB-1 models used the 1,500-horsepower 244 engine. Later FA-2 and FB-2 versions increased this to 1,600 horsepower and featured a lengthened carbody. This extra space allowed for larger steam generators for passenger service. While these locomotives offered impressive pulling power and a stylish appearance, the 244 engine initially faced reliability issues. This allowed EMD to maintain market dominance, though many ALCO units remained in service for decades across North America.