EMD FP10

Electro-Motive Division (EMD)
Industry	Locomotive manufacturing
Headquarters	La Grange, United States
Products	Diesel locomotives

The EMD F3 is a diesel locomotive featuring a B-B wheel configuration, manufactured by General Motors’ Electro-Motive Division between July 1945 and February 1949. The final assembly took place at GM-EMD’s facility in La Grange, Illinois. Production numbers reached 1,106 lead A units equipped with cabs and 694 cabless booster B units.

As the third iteration in GM-EMD’s prominent EMD F-unit lineup, the F3 ranks as the second most produced model. It succeeded the EMD F2 by incorporating the more powerful D12 generator and distinguished itself from the subsequent EMD F7 primarily through its electrical components. Some late-production F3 units were outfitted with F7-style D27 traction motors and reinforced electrical wiring; these were informally referred to as model F5 within EMD’s engineering circles.

Design

The F3 was equipped with a mechanically aspirated V16, two-stroke 567B diesel engine generating at 800 rpm, with a total displacement of . Power was delivered via a direct current D-12 generator to four traction motors mounted on Blomberg B trucks. The locomotive could be configured for either freight or passenger operations, achieving speeds up to when fitted with passenger gearing.

The carbody design for A units progressed through four distinct phases: Phase I resembled the F2 with three side portholes and “chicken wire” grilles; Phase II reduced the number of portholes to two and introduced wire mesh between them; Phase III eliminated the mesh entirely; and Phase IV replaced the upper wire mesh with stainless steel grilles. Some Phase IV models were colloquially labeled F5, although this was never an official classification.

Between 1978 and 1979, eighteen F3 locomotives along with one F7 were rebuilt into FP10 units for commuter rail service. These rebuilds included the installation of head-end power generators and alterations to side panels that replaced the original portholes.

History

The F3 was designed as the successor to the successful EMD FT locomotive, incorporating three main enhancements: an optimized interior layout for quicker assembly, an upgraded prime mover delivering (up from ), and a new D12 main generator to handle increased power demands. Early demonstration units revealed issues that prompted EMD to introduce the F2, which utilized the FT’s D4 generator limiting output to . During this period, 104 F2 units were built while EMD addressed problems with the D12 generator. Full-scale production of the F3 commenced in November 1946.

The widespread adoption of the F3 significantly hastened dieselization across the United States. For instance, the Missouri–Kansas–Texas Railroad evaluated EMD’s demonstration unit against its existing fleet of 2-8-2 steam locomotives before ordering 21 F3s and completing dieselization by 1952.

Original owners

Approximately 1,800 F3 locomotives were produced by EMD: 1,106 cab-equipped A units and 694 cabless B units. Forty-nine railroads acquired A units, while thirty-nine also purchased B units. The largest purchasers included Union Pacific Railroad, Southern Railway, and Southern Pacific Railroad, which obtained 179, 178, and 160 units respectively. Other significant operators were the Pennsylvania Railroad, Chicago, Burlington and Quincy Railroad, and Atchison, Topeka and Santa Fe Railway.

Preservation

A number of F3 locomotives have been preserved within museums and heritage railways such as:

References

External links