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Original price $629.99 - Original price $629.99
Original price $629.99
$629.99 - $629.99
Current price $629.99

Athearn Genesis G1009 HO Scale 4-6-6-4 Challenger w/Coal Tender Union Pacific UP 3911 DCC/Sound

ALCO constructed the first 4-6-6-4 locomotives in the world, numbered 3900 to 3914, for the Union Pacific Railroad in 1936. These huge engines were named the Challenger Simple Articulated, or CSA-1, class. The railroad received 25 near copies, classified as CSA-2, the following year.

Unlike compound Mallet engines that crawled along with drag freights, the Challengers had two sets of high- pressure cylinders and could safely reach passenger train speeds. The mammoth locomotives also had a heavy-duty starting tractive effort of 97,400 pounds.

Originally constructed to haul fast freight up the famous Wasatch grade, the CSA-1 and -2 Challengers would hold a variety of assignments over their long careers- including passenger service. Depending upon their operating territory, they burned either coal or oil, and some locos were converted back- and-forth several times.


  • #3911 Class CSA-1, Worthington feedwater heater, standard sand dome, boiler-tube pilot with wide handrails, no walkway “hump”, steam pipe to front cylinders, blackened metal side rods, satin paint finish, coal burners. Era 1936+
  • Illuminated number boards and headlights
  • Headlight turns off in reverse
  • Illuminated directional back-up light in the tender
  • Correctly operating eccentric cranks
  • Adjustable top cab vent and cab windows
  • Pivoting front and rear engines for negotiating 18” radius curves
  • Current pick-up on all driver and wheels
  • Boiler backhead with full details and printed gauges
  • Synchronized chuff, whistle, bell, blow-down, air compressor, dyno and pop-off valve sounds
  • User-controlled whistle, short whistle, bell, squeal, coupler crash, injector, water stop and light dimmer
  • Individually-applied detail parts, including brass-painted bell and whistle, piping, valves, generator, steps, air pump, air tanks, reverser and coupler lift bar
  • Front coupler pocket can be inserted to mount operating coupler
  • Dual cube speakers for great sound quality
  • Upgraded headlight lighting with brighter LED
  • Improved loco-to-tender connection harness for increased durability and serviceability
  • Minimum recommended radius: 22”
    • Tender-mounted 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
    • Engine, whistle, and bell sounds work in DC
    • 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


  • Era: 1911-1940
  • Prototype Manufacturer: American Locomotive Company (ALCO)
  • Full Road Name: Union Pacific
  • Scale: HO
  • Wheel Configuration: 4-6-6-4
  • Sub Brand: ATHEARN
  • Minimum Radius: 22" (559 mm)
  • Reporting Mark: UP
  • Lighted: LED
  • Sound: Tsunami2
  • DCC: Equipped