Union Pacific 'Challenger' Project Information
Kohs & Company Version #5 Production Model
The Union Pacific 3900 class Challengers are considered by many railroading fans to be the most handsome steam prototypes ever built. This prototype class was selected as a project for two reasons; their outstanding service in moving huge amounts of fast freight across the western half of the United States during the all important war years and their service in heading up some of the most legendary passenger consists of the period. Our project consists of UP 4664-3, 4 & 5 class locomotives in six (6) versions plus the Rio Grande L-97 units and the single-stack Clinchfield E-3's. (Products bearing Union Pacific and Rio Grande marks are made under trademark license from Union Pacific Railroad Company)
A Twin Function Custom Built Dallee Electronics Sound System with Specially designed Speaker System
Twin Custom Wound Ball-Bearing Equipped Pittman Motors
Purpose Designed Ball-Bearing Equipped Drive Mechanism
Stainless Steel Scale Profile Tires on All Wheel Sets
Nickel Silver Rods and Valve Gear
Constant Voltage Lighting System
Full Under-body Detail on Locomotive & Tender
All directional lighting can be controlled both automatically and manually using the included control box which is also used to control the sound functions. All remote features are assignable as DCC functions
Fully Equalized and Sprung Suspension with Fabricated Leaf Springs
56 Ball-Bearing Units used throughout the model
Ball-Bearing Equipped Side & Main Rods
User Controlled Electronically Operated Valve Gear on both Engines
Full Cab Detail: Wood Liner, Brass Gauge Bezels & Lenses
Prototypical Operating Buffer Assembly between Loco & Tender
All Hatches and Compartments are Operational
A now standard feature is the prototypically built and hung running boards which are mounted on miniature brackets extending from the boiler jacket, you can see daylight between the running board and boiler
(click on version name to view prototype photos)
Version 1 - Early Coal - Each of the three production orders included in this version had unique detailing and our models will reflect that. The available road numbers and the production orders to which they belonged were: the first production order road numbers were 3950-3969, the second production order road numbers were 3975-3999 and the third production order road numbers were 3930-3949. Paint scheme: Black overall, Graphite smokebox & firebox and Aluminum color markings.
Version 2 - Coal 3967 (10 Models) - This version is the same as version #1 with the addition of wind wings (smoke lifters). Road number 3967 was one of two coal fired locomotives to have wind wings installed and was the only one to keep them until the end of service. Paint scheme: Black overall, Graphite smokebox & firebox and Aluminum color markings.
Version 3 - Late Coal - This version incorporates a number of substantial modifications made during the mid-service period, which included: new pilot, new firebox arrangement, relocated generator, ATC (automatic train control) equipment and extended coal boards. By the late service period eighteen locomotives had been converted to oil firing so the remaining appropriate road numbers for this version are: 3933, 3935, 3936, 3939-3942, 3945-3974, 3985-3999. Paint scheme: Black overall, Graphite smokebox & firebox and Aluminum color markings.
Version 4 - Early Oil Fired - The conversion to oil firing required substantial changes to the firebox and cab area of the locomotive, altered cab interior arrangement and a fuel tank in the coal bunker of the tender. Prior to being painted in the passenger paint scheme these eight locomotives had ‘wind wings’ installed, our models have removable ‘wind wings’ so that either period of operation can be modeled. The appropriate road numbers are: 3975-3984. Paint scheme: Black overall, Graphite smokebox & firebox and Aluminum color markings.
Version 5 - Passenger Paint Scheme (10 Models) - This is the same as our version #4 model, but with the famous two-tone gray passenger paint scheme with silver-grey stripes. Road numbers: 3975-3984.
Version 6 - Late Oil Fired - The late ‘oil’ version combines the design features of version #4 with the late modifications included on the version #3 models. Road numbers: 3700-3717. Paint scheme: Black overall, Graphite smokebox & firebox and Aluminum color markings.
Version 7 - Rio Grande (5 Models) - This is the Rio Grande L-97 variation of our Challenger. With Rio Grande markings, it has detailing much the same as our version #1 second production order models. The applicable road numbers are: 3800-3805. Paint scheme: Black overall, Graphite smokebox & firebox and White markings.
Version 8 - Clinchfield (5 Models) - This is the Clinchfield E-3 class variant complete with single large exhaust stack. The basic features of this version are similar to version #1 second production order models with modifications made once in Clinchfield service. The Clinchfield E-3’s had road numbers: 670-675. Paint scheme: Black overall, Graphite smokebox & firebox and Yellow markings.