EMD SDP40F

Infobox Locomotive
name=EMD SDP40F
powertype=Diesel-electric
gauge= RailGauge|ussg


caption=An EMD SDP40F while in Amtrak service. Note that these locomotives were equipped with steam generators, used to power heating and cooling equipment on passenger trains up to the 1970s, prior to the adoption of Head End Power.
builder=General Motors Electro-Motive Division (EMD)
builddate=June 1973 – August 1974
aarwheels=C-C
primemover=EMD 645E3
cylindercount=V16
poweroutput= convert|3000|hp|abbr=on|sigfig=3
totalproduction=150
topspeed=convert|95|mph|abbr=on
length= convert|72|ft|4|in|abbr=on
width= convert|10|ft|4|in|abbr=on
locobrakes=straight air, dynamic
trainbrakes=air
locale=United States
buildmodel=SDP40F

The EMD SDP40F was a 6-axle diesel locomotive built by General Motors Electro-Motive Division from 1973 for Amtrak service. Power was provided by an EMD 645E3 16-cylinder diesel engine, which generated 3000 tractive horsepower (2240 kW).

These locomotives were Amtrak's first series of locomotives built new. Amtrak acquired 150 of them over a two year period. They were based on a standard freight locomotive design, the ubiquitous SD40-2.

Derailments

Although the locomotives were mechanically reliable, several serious derailments occurred causing the railroads over which Amtrak operated to impose severe speed limits on the SDP40F. While the "hollow bolster" truck design was suspected as a cause, subsequent testing by both Amtrak and the Federal Railroad Administration, never definitively discovered the source of the continued derailments.

Whatever the cause, the restrictions on the use of the SDP40F, plus the rapidly advancing electrification of Amtrak's passenger car fleet, ultimately led Amtrak management to adopt the F40PH as their standard model, based on the proven design of the GP40-2 freight locomotive. The railroad worked out a deal with EMD to trade-in the SDP40Fs in on the F40PH over a period of years. A limited number of SDP40Fs were fitted with head end power equipment.

Withdrawal

As the F40PHs increased in number on the Amtrak system, the SDP40F was gradually withdrawn from service. The last revenue run of an SDP40F under Amtrak took place in 1985. In an unusual move for modern railroading, 18 were traded by Amtrak to the Santa Fe Railroad in 1984 to be reconditioned for use as freight locomotives, in exchange for 43 smaller locomotives for use by Amtrak as yard switchers. Both railroads benefited from the exchange. The units Santa Fe acquired had a reliable service record, and it is worth noting that one Santa Fe railroad official suggested at the time that the SDP40F's derailment issue was caused simply by the large amount of water these locomotives carried on-board to feed their steam generators; one large tank located over the rear truck contained twenty tons of water that would slosh back and forth on rough track. Certainly, once the Santa Fe removed the water tanks and steam generators and replaced them with steel and concrete weights, the locomotives exhibited no tendency to derail.

The last run of an SDP40F took place in 2001 on the BNSF; the units were all officially retired in 2002. Most were scrapped in Topeka, Kansas between 2002 and 2004.

Preservation

One locomotive of the type, former Amtrak 644, has been preserved and is located in the Portland, OR area and is currently in Service on the Portland and Western Railroad. Two other heavily modified SDP40F lettered/painted for EMD exist as test beds at the AAR testing center in Pueblo, CO. It is unknown what their internal configuration is, or what the future holds for them.

References

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External links

* [http://hebners.net/amtrak/ Amtrak Photo Archives]