PROTOTYPE SPECIFIC INFORMATION

EMD introduced the new 3,500 horsepower SD50 in May of 1981 as part of their planned “50 Series”. The SD50 was, in essence, a transition model of the 1970s era Dash 2 series of locomotive.

Originally produced by EMD as an immediate response to General Electric’s Dash 7 line of locomotives which were becoming more favorable with current roads—providing more competition for EMD. While EMD’s current SD40-2 model provided a reliable locomotive for most class 1 railroads at the time, GE Transportation was gaining more inroads with the 3,600hp Dash 7s. The Dash 7s boasted more modern technology and GE Transportation was providing competitive financing and maintenance programs to assist purchasers of their offerings. While EMD’s SD45 and SD45-2s - with their 3,600 horsepower were successful, the large 20-cylinder engines were not fuel-efficient. This lack of efficiency, alongside reported issues of reliability, caused many railroads to rethink their motive power provder. This was further magnified in the 1970s when the fuel crisis impacted general transportation as well as the railroad industry.

In May of 1981, EMD unveiled the new SD50 which would feature an updated version of the V16 645 from the venerable SD40-2, upgraded to 3,500 hp at 900rpm. The SD50 had a longer frame and much longer long hood than its predecessors. Other improvements came from moving the dynamic brake resistors for the dynamic brake grid from the traditional location above the prime mover to a cooler temperature location in front of the engine compartment air intakes, closer to the electrical switchgear. This, in turn, separated them from other systems, resulting in simplified maintenance for both the prime mover as well as the electrical system. A grand total of 426 units were produced when production ceased in Feb of 1986.

 

SD50 SERIES LOCOMOTIVE NEW FEATURES:

• New tooling from the rails up!

• New bodies with correct door placement and weld marks

• Early or late handrail placement

• HTC or Flexicoil trucks with Hyatt or animated Timken bearings

• Correct dymanic brake intake and exhaust grille placement

• Single or dual conduit fans

• Rounded or blunt anticlimbers with or without MU cutouts

• 4000 or 4500 gallon fuel tanks with fuel fillers, fuel gauges, & breather pipes; correct gauge and filler placement

• Operating Class Lights (Where equipped based on prototype)

• Operating Number boards

• Coupler cut levers

• Trainline hose

• Full cab interior

• Windshield wipers

• Wire grab irons

• MU hoses

• See-through cab windows

• Walkway tread

• Lift rings

• Sander lines

• DCC-ready features Quick Plug plug-and-play technology with 21-pin NEM connector

• Fine-scale Celcon handrails for scale appearance

• Body-mounted McHenry operating scale knuckle couplers

• Genesis driveline with 5-pole skew wound motor, precision machined flywheels, and multi-link drivetrain for trouble free operation

• All-wheel drive with precision gears for smooth and quiet operation

• All-wheel electrical pickup provides reliable current flow

• Wheels with RP25 contours operate on all popular brands of track

• LED Lighting for trouble free operation

• Heavy die-cast frame for greater traction and more pulling power

• Scaled from prototype resources including drawings, field measurements, photographs, and more

• Accurately-painted and –printed paint schemes

• Packaging securely holds the model for safe storage

• Minimum radius: 22”

 

SOUND-EQUIPPED MODELS ALSO FEATURE

• Onboard DCC decoder with SoundTraxx Tsunami2 sound

• Dual cube speakers for optimal sound quality

• Sound units operate in both DC and DCC

• Full DCC functions available when operated in DCC mode

• All functions NMRA compatible in DCC mode

• Precision slow speed control

• Program a multiple unit (MU) lashup with lead unit only horn, bell, and lights

• Many functions can be altered via Configuration Value (CV) changes

• CV chart included in the box

 

Denver & Rio Grande Western

The Denver and Rio Grande Western purchased 17 SD50s from EMD in the late summer of 1984. Built with Chessie System specs, these units were delivered with K5LA horns, “mail slot” battery boxes and hood-mounted bells however the gyralights D&RGW was so well known for were absent. Gyralights however were soon added to SD50 units #5501 – 5517 once officially on the property. Our models will include the familiar operating nose gyralights (DCC version only) and rerail frogs.

 

DRGW FEATURES:

• Nathan K5 horn

• Long hood-mounted bell

• EMD HTC trucks with animated Timken bearings

• Chessie “mail slot” battery box doors with added screens

• Early frame with diagonal pilot cutouts and rounded anticlimbers

• 4000 gallon fuel tank

• Nose gyralight (Effect in DCC)

 

 

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