North American Locomotive Works

Union Pacific Steam MegaPack
FEF-3 Class 4-8-4 Northern, Challenger Class 4-6-6-4,
Big Boy Version 2, Smoothside Coach Set

Available at

Model description:
Get ready and hold on! The UP Steam MegaPack from North American Locomotive Works has arrived. This set features two new Big Boys, three Northerns and three Challengers, with a full complement of coaches to go with them. What you'll get is:

Version 2 of the NALW Big Boy, road numbers 4005 and 4012. These feature updated physics and visual effects, and are very nicely weathered. New custom sounds, including exterior compressor and brake sounds, are included in this update.

Three UP Challengers, featuring the same enhanced effects as the BigBoy V2.0. They make perfect additions to your UP steam fleet. These new models are uniquely skinned as:
        3977 - Skinned in the later two-tone grey passenger scheme, with UP Silver Grey.
        3979 - Standard UP black, but weathered and dirty
        3985 - Standard UP black, lightly weathered with just a bit of road grime.

Three FEF Northerns, featuring customized cab and sounds. Like the Challengers, these are completely new models:

        838 - Skinned in the UP "Greyhound" passenger scheme, with no weathering. 838 is skinned in the original UP two-tone grey passenger scheme, featuring Armour Yellow lettering and striping
        840 - Skinned in the later two-tone grey passenger scheme, with UP Silver Grey.
        844 - Skinned in UP standard Black, with no weathering. Perfect for excursion service.

UP Smoothside Passenger set. This passenger car set includes UP smoothside baggage cars, coaches, sleepers, diners, domes and business car. Perfect to hook up behind a Northern or a Challenger for excursions.

Also included is an auxiliary excursion tender for those long trips. Eight sample consists make up the rest of the package (with two excursion consists). Enjoy!

FEF-3 History
4-8-4 class locomotives were known by several names by various roads. In general, they are referred to as the Northern, for the first road to use the type (Northern Pacific) in 1927. Northerns quickly became the near-standard late American locomotive class for fast freight and passenger service. In total, 1,120 4-8-4 locomotives were built and operated in North America. Of this total, the Union Pacific Railroad operated 45 Alco built FEF-1, -2, and -3 class 4-8-4s. The first of these 800's were delivered in 1937. Over their lifespan, the 800's design and configuration was altered to improve performance and reduce smoke flow over the cab, a problem that persisted with the engines until the introduction of the elephant ears and dual stacking. The latter alteration also had the effect of increasing engine power and efficiency through the reduction of exhaust back pressure. All FEF-class engines were built for coal firing, but the threat of a coal strike at the end of the war prompted UP to convert these engines to oil firing. The conversion to oil also had the benefit of providing additional smokebox space. Onefoot was added for the inclusion of a Worthington model SA feedwater heater.
    The FEF-3 locomotive was the subject of testing by the AAR in 1938, along with other current state-of-the art locomotives, to further advance steam locomotive designs. AAR identified the need for future designs to be faster and stronger, to allow rail travel to compete with the emerging airline and highway system. During these tests, UP #815 distinguished itself above both the Pennsylvania K4 and the C&NW 4-6-4 Hudson by its ability for sustained running at 102 mph, 7 mph faster than the Hudson.
   Union Pacific continues to maintain and operate one FEF-3 locomotive (844) as part of its steam program.

Challenger History
Union Pacific was one of the few railroads that could acquire new motive power during the Great Depression. Together with Alco and lead mechanical engineer Arthur H. Fetter, the railroad set about designing a new fast freight steam engine. UP wanted to expand its fleet of fast freight engines, but desired an engine that could negotiate tighter curves than the rigid wheelbase 4-12-2. Alco took the lead in the design effort. Well aware of the instability problems of Baltimore & Ohio's 2-6-6-2s, Alco elected to employ a four-wheel engine truck,thus designing what was a 4-12-2, split in half.
   The instablility problem was solved by moving the boiler forward in order to shift more weight onto the front engine. This meant that the firebox could not be placed behind the rear set of driving wheels, as with a 2-6-6-4, but rather, had to be was supported both by the rear pair of drivers and the trailing truck, creating a 4-6-6-4. The 4-6-6-4 was actually an evolution of the UP 4-12-2 class 9000 compound freight locomotive. The Challengers are just slightly heavier than the Nines, but are faster because of the lighter side rods and better balance achieved in the articulated design.
   Alco delivered thirteen engines in 1936. Union Pacific was not disappointed, and over the next seven years went on to order a total of 105 4-6-6-4s, built to two different designs: the early Alco design and a later UP design. A Union Pacific official christened the engine 'Challenger.'
   The first 4-6-6-4, UP number 3900, was received from Alco at Council Bluffs on August 25, 1936, and after a brief ceremony it headed west pulling a refrigerator train. Six Challengers were asssigned to passenger service. In total, Alco delivered 105 of the class to UP, while eight other railways bought 4-6-6-4 class locomotives. In total, 252 were built. Of these, two survive and the 3985 continues to run in UP's steam program.

Road Numbers
Northern: 838, 840, 844
Big Boy: 4005, 4012 (see specs)
Challenger: 3977, 3979, 3985

FEF-3 Northern Specs
Weight: 907,980 lbs. or 454 tons Engine & Tender
Length: 114 ft. 2-5/8 in. Engine & Tender
Tender Type: 14-wheeled
Water Capacity: 23,500 gallons
Fuel: 6,000 gallons
No. 5 oil
Gauge of Track: 4 ft. 8-1/2 in.
Cylinder: Diameter: 25 in.
Stroke: 32 in.
Driving Wheel Diameter: 80 in.
Boiler: Inside Diameter: 86-3/16 in.
Pressure: 300 lbs.
Fire Box: Length: 150-1/32 in.
Width: 96-3/16 in.
Tubes: 2-1/4 in. Diameter: 198 x 19 ft. 0 in.
5-1/2 in. Diameter: 58
Wheel Base: Driving: 22 ft. 0 in.
Engine: 50 ft. 11 in.
Engine & Tender: 98 ft. 5 in.
Weight in Working Order,
Pounds: Leading: 102,130
Driving: 266,490
Trailing: 117,720
Engine: 486,340
Tender: 421,550
Evaporating Surfaces,
Square Feet: Tubes: 2,204
Flues: 1,578
Fire Box: 442
Circulator & Arch Tubes: Removed, 1945
Total: 4,224
Superheating Surface,
Square Feet: 1,400
Grate Area: Removed, 1945
Maximum Tractive Power: 63,800 lbs.
Factor of Adhesion: 4.18

Challenger Specs
Tender Type: 14-wheeled
Water Capacity: 25,000 gallons
Fuel: 5,945 gallons
No. 5 oil
Gauge of Track: 4 ft. 8-1/2 in.
Cylinder: Diameter: 21 in.
Stroke: 32 in.
Driving Wheel Diameter: 69 in.
Boiler: Inside Diameter: 94-11/16 in.
Pressure: 280 lbs.
Fire Box: Length: 187-1/32 in.
Width: 108-3/16 in.
Tubes: 2-1/4 in. Diameter: 45 x 20 ft. 0 in.
4 in. Diameter: 177
Wheel Base: Driving: 12 ft. 2 in. & 12 ft. 2 in.
Engine: 60 ft. 4-1/2 in.
Engine & Tender: 121 ft.10-7/8 in.
Weight in Working Order,
Pounds: Leading: 102,300
Driving: 404,000
Trailing: 121,600
Engine: 627,900
Tender: 441,900
Evaporating Surfaces,
Square Feet: Tubes: 527
Flues: 3,687
Fire Box: 500
Circulators: 81
Total: 4,795
Superheating Surface,
Square Feet: 2,162
Grate Area: Removed, 1990
Maximum Tractive Power: 97,350 lbs.
Factor of Adhesion: 4.17

The UP "Greyhound" paint scheme
Union Pacific's two-tone paint scheme first came into use in about mid-1946, to match a similar paint scheme in use by The Pullman Co. on its passenger cars since the late 1930s. Two-tone gray paint was used on most, if not all, of the steam locomotives assigned to passenger, including the 4-6-2 Pacifics, the 4-8-2 Mountains, the 4-8-4 Northerns. Also included were a group of ten oil-burning 4-6-6-4 Challengers assigned to the Northwestern District passenger service. The passenger Challengers eliminated the use of helpers and double-headers on passenger trains, enabling 4-8-2 Mountains and other smaller power to be assigned to other duties.
    As originally applied, the color of the striping and lettering was Armour Yellow. This bit of yellow color was apparently intended to match the yellow color on the Streamliners since these steam locomotives were originally intended to be used as standby power on these premium trains. In 1949, the color of the striping and lettering was changed from Armour Yellow to Silver Gray.
    Of the 10 Challenger locomotives in the UP 3975-3984 series assigned to this service, at least nine locomotives were painted to two-tone gray in 1946. Along with two-tone gray paint, all ten locomotives also received smoke lifters, or smoke wings, a new feature added after October 1945 and intended to keep smoke out of the cabs and away from the operating crews. The ten two-tone gray Challengers operated mostly in passenger service, but occasionally turned up in freight service.

Model and Base Textures: Jens-Chris Baerenz
Final Textures: John Fowlis and Harold Clitheroe
Lighting: Kelley Ellison
Cab View: Graeme Cox
Original sound samples: Matt Donnelly, Joseph Realmutto, Steve Thompson
Sound engineering: Harold Clitheroe, Chuck Schneider
Physics: John Fowlis, Chuck Schneider
Beta Testing: Harold Clitheroe, John Fowlis, Chuck Schneider, Michael MacFall
Assembly and Packaging: Michael MacFall

© 2002 North American Locomotive Works. All rights reserved.


All release dates subject to change without notice.

© 2002 North American Locomotive Works. All rights reserved.