General Motors Electro-Motive Division F40PH series
The General Motors Electro-Motive Division F40PH series is a 4-axle lightweight diesel-electric locomotive originally designed for service with Amtrak. Built from 1976 to 1992, it was essentially a GP40-2 with a full-width body on the shorter GP35 frame, although over time the design, both in appearance and mechanically, evolved considerably. Contrary to the name, all F40's are fitted with Dash-2 equipment, although the last units built have more advanced equipment.
When Amtrak took over the passenger services of the American freight railroads in 1971, a need was immediately foreseen for a variety of different equipment to replace most of the antiquated rolling stock purchased or leased from the railroads, not the least of which was motive power. Two types of diesel locomotives were immediately identified: the first, a large high-horsepower diesel, at first equipped with steam generators but able to be equipped with Head-End Power (HEP) equipped with large fuel and water reserves and to be used on long-distance trains; the second, a smaller, lighter and faster unit equipped only with HEP (and to be used with the then-upcoming Amfleet I cars) to be used on shorter distance corridors.
Of these two types, it was felt that the first was to be the priority. EMD won the tender for what eventually became 150 units (although Amtrak did agree to purchase 25 HEP-equipped P30CH's from GE at the same time), and the SDP40F was born.
The second became the F40PH: Amtrak 200-229 were delivered in 1976, and immediately went to work on a number of short-distance corridors, including New York to Boston. They differed mechanically however, in that the HEP alternator was mechanically coupled to the main engine rather than using separate skid-mounted "gensets" as was envisioned with the SDP40F's. Because of the need to keep the frequency constant at 60 Hz, the engine must turn at a constant rate regardless of the output of the engine. As an example, the engines of VIA's own F40's normally have an output of 3000hp (~2240kW), but must run at a slower speed when producing HEP and therefore only have an output of 2400hp before the HEP requirements (about 45kW per passenger coach).
Because of "parasitic" requirements of the HEP and other accessories on traction output, most F40's were actually delivered with engines that put out 3200hp, and those that weren't were often upgraded. VIA's are among the few delivered that still put out 3000hp.
Shortly after the second batch of SDP40F's entered service however, a number of troubling derailments occurred, always on shallow curves and always on the trailing unit. The lightweight hollow-bolster version of the truck they used was immediately suspected, and all trains led by SDP40F's were forced to slow down substantially for curves, throwing long-distance schedules out the window. Although the derailment issues were later traced to the above-frame water tanks for the dual steam generators, the damage was done to the reputation of the SDP40F. For the second batch of F40PH's, 25 almost-new SDP40F's were traded in and various parts reused.
Amtrak continued to purchase more and more F40PH's (many of them reusing parts of traded-in SDP40F's) until by 1984 they had a fleet of 210 units.
Amtrak wasn't the only one who saw the use of the type though. Many commuter agencies also saw the benefit of modernizing their fleets with F40PH's, including Metra (who ordered 115 of several types), GO Transit, MBTA and Caltrain. VIA Rail Canada purchased 2 orders of F40's in the late 1980's when they updated much of their old steam-heated equipment with HEP.
In 1987, MBTA approached EMD about producing a version of the F40 with a separate HEP genset for improved fuel economy, and the F40PH-2C was born. So popular was this concept that a competitor has managed to make a very good business building "knock-offs" (although many of these are substantially improved from the EMD version).
Variants
- EMD F40PH
- EMD F40PHR
- EMD F40PH-2
- EMD F40PH-2C
- EMD F40PH-2D
- EMD F40PHM-2
- M-K F40PHM-2C
- MPI F40PH-2C
- MPI F40PH-3C
- MPI F40PH-4C
