EMD SDP40F
Encyclopedia
The EMD SDP40F was a 6-axle Diesel-electric locomotive built by General Motors Electro-Motive Division from 1973 for Amtrak
service. Power was provided by an EMD 645E3 16-cylinder
turbocharge
d Diesel engine
, which generated 3000 tractive horsepower
(2240 kW).
Based on EMD's ubiquitous SD40-2 freight locomotive
, a total of 150 SDP40Fs were placed into service over a two year period. Using a passenger style carbody instead of the narrow long hood of the antecedent freight unit, the SDP40F had 57:20 passenger gearing permitting a maximum speed of 100 mph (44.7 m/s) and two Vapor steam generators
, along with a 1350 US gal (1,124 imp gal; 5,110 l) feedwater tank, at the rear of the engine room
. (Another tank below the frame carried 2150 more gallons of water.) Steam was required for climate control and potable water heating systems of the passenger fleet that Amtrak was operating at the time.
Eventually the SDP40F was phased out as all-electric cars, such as the Amfleet
, displaced the old steam heat rolling stock. Amtrak was able to trade in the SDP40F to EMD as the head end power
-equipped F40PH
was acquired.
s, causing the railroads over which Amtrak operated to impose severe speed limits starting in 1976-77. Although the "hollow bolster" truck design was suspected, this was never conclusively proved, despite extensive investigation by EMD, Amtrak and the Federal Railroad Administration
. It was subsequently thought that the combined weight of the steam generators and water tank at the rear of the locomotive may have resulted in uneven weight distribution, causing poor loading on the leading truck. Also playing a role was the mediocre condition of much of the trackage on which the SDP40F operated.
Whatever the derailment cause, the speed restrictions, along with the advancing electrification of Amtrak's passenger car fleet, ultimately led Amtrak management to adopt the F40PH as the standard model, based on the proven design of the GP40-2
freight locomotive.
As the F40PHs increased in number on the Amtrak system, the SDP40F was gradually withdrawn from service.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 was 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, Amtrak received 43 smaller locomotives for use in switching service, a deal that was beneficial to both railroads.
The last run of an SDF40-2 on BNSF took place in 2001. All units were officially retired in 2002, and most were scrapped in Topeka, Kansas between 2002 and 2004.
Amtrak
The National Railroad Passenger Corporation, doing business as Amtrak , is a government-owned corporation that was organized on May 1, 1971, to provide intercity passenger train service in the United States. "Amtrak" is a portmanteau of the words "America" and "track". It is headquartered at Union...
service. Power was provided by an EMD 645E3 16-cylinder
Cylinder (engine)
A cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...
turbocharge
Turbocharger
A turbocharger, or turbo , from the Greek "τύρβη" is a centrifugal compressor powered by a turbine that is driven by an engine's exhaust gases. Its benefit lies with the compressor increasing the mass of air entering the engine , thereby resulting in greater performance...
d Diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
, which generated 3000 tractive horsepower
Horsepower
Horsepower is the name of several units of measurement of power. The most common definitions equal between 735.5 and 750 watts.Horsepower was originally defined to compare the output of steam engines with the power of draft horses in continuous operation. The unit was widely adopted to measure the...
(2240 kW).
Origins
The SDP40F was the first locomotive type purchased new by Amtrak. Amtrak's initial motive power fleet was primarily EMD E-units and F-units acquired from predecessor railroads. Most of these veteran locomotives had been in operation for many years without good maintenance, resulting in numerous breakdowns. New locomotives were needed quickly, and the SDP40F was intended as an interim solution to Amtrak's long-term motive power requirements.Based on EMD's ubiquitous SD40-2 freight locomotive
EMD SD40-2
The EMD SD40-2 is a C-C locomotive produced by EMD from 1972 to 1989.The SD40-2 was first introduced in January 1972 as the mid-range offering in EMD's six-axle "Dash-2" series, competing against the GE U30C and the MLW M630...
, a total of 150 SDP40Fs were placed into service over a two year period. Using a passenger style carbody instead of the narrow long hood of the antecedent freight unit, the SDP40F had 57:20 passenger gearing permitting a maximum speed of 100 mph (44.7 m/s) and two Vapor steam generators
Steam generator (railroad)
Steam generator is the term used to describe a type of boiler used to produce steam for climate control and potable water heating in railroad passenger cars...
, along with a 1350 US gal (1,124 imp gal; 5,110 l) feedwater tank, at the rear of the engine room
Engine room
On a ship, the engine room, or ER, commonly refers to the machinery spaces of a vessel. To increase the safety and damage survivability of a vessel, the machinery necessary for operations may be segregated into various spaces, the engine room is one of these spaces, and is generally the largest...
. (Another tank below the frame carried 2150 more gallons of water.) Steam was required for climate control and potable water heating systems of the passenger fleet that Amtrak was operating at the time.
Eventually the SDP40F was phased out as all-electric cars, such as the Amfleet
Amfleet
Amfleet is a series of intercity railroad passenger cars built for the operator Amtrak by the manufacturer Budd Company in two series during the late 1970s and early 1980s. Today, Amfleet cars are used extensively throughout the Amtrak system outside the western United States...
, displaced the old steam heat rolling stock. Amtrak was able to trade in the SDP40F to EMD as the head end power
Head end power
Head end power or electric train supply is a rail transport term for the electrical power distribution system on a passenger train. The power source, usually a locomotive at the front or “head” of a train or a generator car, generates all the electricity used for lighting, electrical and other...
-equipped F40PH
EMD F40PH
-Amtrak NPCU Conversions:In later years, as Amtrak's F40PH fleet was being replaced by the newer GE Genesis-series locomotives, Amtrak converted a number of the retired units—generally ones with major mechanical problems limiting their value in the resale or lease marketplace—into "Non-Power...
was acquired.
Derailments
The SDP40F was mechanically reliable but experienced several high speed derailmentDerailment
A derailment is an accident on a railway or tramway in which a rail vehicle, or part or all of a train, leaves the tracks on which it is travelling, with consequent damage and in many cases injury and/or death....
s, causing the railroads over which Amtrak operated to impose severe speed limits starting in 1976-77. Although the "hollow bolster" truck design was suspected, this was never conclusively proved, despite extensive investigation by EMD, Amtrak and the Federal Railroad Administration
Federal Railroad Administration
The Federal Railroad Administration is an agency in the United States Department of Transportation. The agency was created by the Department of Transportation Act of 1966...
. It was subsequently thought that the combined weight of the steam generators and water tank at the rear of the locomotive may have resulted in uneven weight distribution, causing poor loading on the leading truck. Also playing a role was the mediocre condition of much of the trackage on which the SDP40F operated.
Whatever the derailment cause, the speed restrictions, along with the advancing electrification of Amtrak's passenger car fleet, ultimately led Amtrak management to adopt the F40PH as the standard model, based on the proven design of the GP40-2
EMD GP40-2
An EMD GP40-2 is a 4-axle diesel road switcher locomotive built by General Motors Electro-Motive Division as part of its Dash 2 line between April 1972 and December 1986. Power was provided by an EMD 645E3 16-cylinder engine which generated 3000 horsepower .- Production :Standard GP40-2 production...
freight locomotive.
Withdrawal
The last run of an SDF40-2 on BNSF took place in 2001. All units were officially retired in 2002, and most were scrapped in Topeka, Kansas between 2002 and 2004.