Denver & Rio Grande Western 4-6-6-4 "Challenger" Type Locomotives

Class L-105 (Locobase 1345)

Data from D&RGW 1 - 1952 Locomotive Diagram supplied in May 2005 by Allen Stanley from his extensive collection.

Firebox had 200 sq ft of heating surface in three thermic syphons and arch tubes as well as 206 sq ft in the combustion chamber. This second group of five engines had smaller heating surfaces and consequently different ratios.

A third group of six (3800-3805) L-97s were leased from the UP during World War II. They were returned to the UP, which then sold them to the Clinchfield in 1947. See the UP Challenger entry.

Class L-105 (Locobase 339)

Data from D&GRW 1 - 1952 Locomotive Diagram supplied in May 2005 by Allen Stanley from his extensive collection.

Firebox had 200 sq ft of heating surface in three thermic syphons and arch tubes. These were built for dual-service operation over the Continental Divide.

Specifications
ClassL-105L-105
Locobase ID1345339
RailroadDenver & Rio Grande Western (D&RGW)Denver & Rio Grande Western (D&RGW)
Whyte4-6-6-44-6-6-4
Road Numbers3710-37143700-3709
GaugeStdStd
BuilderBaldwinBaldwin
Year19381938
Valve GearWalschaertWalschaert
Locomotive Length and Weight
Driver Wheelbase12.17'12.17'
Engine Wheelbase61.50'61.50'
Ratio of driving wheelbase to overall engine wheebase 0.20 0.20
Overall Wheelbase (engine & tender)
Axle Loading (Maximum Weight per Axle)74721 lbs73669 lbs
Weight on Drivers435472 lbs437939 lbs
Engine Weight641700 lbs641900 lbs
Tender Light Weight393630 lbs394000 lbs
Total Engine and Tender Weight1035330 lbs1035900 lbs
Tender Water Capacity20000 gals20000 gals
Tender Fuel Capacity (oil/coal)26 tons26 tons
Minimum weight per yard of rail on which locomotive could run120.96 lb rail121.65 lb rail
Geometry Relating to Tractive Effort
Driver Diameter70"70"
Boiler Pressure255 psi255 psi
Cylinders (dia x stroke)23" x 32" (4)23" x 32" (4)
Tractive Effort104833 lbs104833 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.15 4.18
Heating Ability
Firebox Area806 sq. ft806 sq. ft
Grate Area136.50 sq. ft136.50 sq. ft
Evaporative Heating Surface57306341
Superheating Surface25252628
Combined Heating Surface82558969
Evaporative Heating Surface/Cylinder Volume186.18206.04
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation34807.5034807.50
Same as above plus superheater percentage45454.2545006.42
Same as above but substitute firebox area for grate area268396.54265752.19
Power L131402.0532888.78
Power MT953.86993.39

Credits

Introduction and specifications provided by Steve Llanso of Sweat House Media.