EMD SDP40F

EMD SDP40F

An SDP40F leads the San Francisco Zephyr west at Emigrant Gap in 1978

Type and origin Power type Diesel-electric Builder GM Electro-Motive Division (EMD) Build date June 1973–August 1974 Total produced 150

Specifications AAR wheel arr. C-C Gauge 4 ft 8 1⁄2 in (1,435 mm) Length 72 ft 4 in (22.0 m) Width 10 ft 4 in (3.1 m) Fuel capacity 2,500 US gal (9,463.5 l; 2,081.7 imp gal) Water cap 3,500 US gal (13,248.9 l; 2,914.4 imp gal) Prime mover EMD 645E3 Engine type V16 diesel Cylinders 16 Loco brake straight air, dynamic brakes Train brakes air

Performance figures Maximum speed 100 mph (160.9 km/h) Power output 3,000 hp (2,237.1 kW)

Career Locale United States

The EMD SDP40F is a six-axle 3,000 hp (2.2 MW) C-C diesel-electric locomotive built by General Motors Electro-Motive Division from 1973–1974. EMD built 150 for Amtrak and for a brief time they formed the backbone of Amtrak's long-distance passenger fleet. A series of derailments in the mid-1970s led to their early retirement in favor of the EMD F40PH. Several were rebuilt and found a second life with the Atchison, Topeka and Santa Fe Railway in freight service.

Amtrak inherited an aging and mechanically-incompatible fleet of diesel locomotives from various private railroads on its startup in 1971. The most modern locomotives remained in private hands to operate the various commuter services which, by law, did not pass to Amtrak. The mainstays of Amtrak's road diesel fleet were veteran EMD E8s and EMD E9s, which were all 10–20 years old and due for replacement.

The design of the SDP40F was based on the EMD FP45 passenger locomotive. Both shared the EMD 645E3 diesel engine (prime mover, although the SDP40F had 16 cylinders instead of 20. The prime mover developed 3,000 hp (2.2 MW). The space saved from the smaller prime mover was given over to increased water capacity. The SDP40F had an underbody tank split between water and diesel fuel, carrying 2,000 US gallons (7,570.8 l; 1,665.3 imp gal) of water and 2,500 US gallons (9,463.5 l; 2,081.7 imp gal) of diesel. A second 1,500-US-gallon (5,678.1 l; 1,249.0 imp gal) water tank sat in the carbody, forward of the steam generators which produced the steam needed for supplying heat (and sometimes cooling) and hot water for the train.