One of the outstanding features on the D&SL is the Moffat Tunnel, a railroad and water tunnel that cuts through the Continental Divide in north-central Colorado. Named after Colorado railroad pioneer David Moffat, the tunnel's first railroad traffic passed through in February 1928.
The East Portal of the tunnel is located fifty miles west of Denver, Colorado. The West Portal is near the Winter Park Resort ski area. The tunnel is 24feet high, 18feet wide and 6.2miles long. The apex of the tunnel is at 9,239feet above sea level. The Moffat Tunnel finally provided Denver with a western link through the continental divide, as both Cheyenne, Wyoming to the north and Pueblo, Colorado to the south already enjoyed rail access to the West Coast. It follows the right-of-way laid out by Moffat in 1902 while he was seeking a better and shorter route from Denver to Salt Lake City. The water tunnel and the railroad tunnel parallel each other; the water tunnel delivers a portion of Denver's water supply.
In 1915, the Denver & Salt Lake Railroad bought eight "Mikado" type locomotives from the Lima Locomotive Works. These locomotives were assigned road numbers 400 through 407. They had 55" diameter drivers, 26" x 30" cylinders, a 200 psi boiler pressure and they exerted 62,700 pounds of tractive effort and each weighed 295,000 pounds. The evaporative heating surface was 4,224 square feet and these locomotives were not superheated. In 1916, two more "Mikados" built by the American Locomotive Company were added the D&SL roster. These two 2-8-2s were very similar to the Lima-built "Mikados".
The D&SL merged with the D&RGW in 1947. All of the D&SL "Mikado" type locomotives were added to the D&RGW roster. They were classified as Class K-63 and assigned D&RGW numbers 1220 through 1229.
There are no surviving Denver & Salt Lake 2-8-2 "Mikado" type locomotives.
|Qty.||Road Numbers||1947 D&RGW Class||1947 D&RGW Numbers||Year Built||Builder||Notes|
|2||408 & 409||K-63||1228 & 1229||1916||ALCO||2|
Data from  and D&SL 1 -1932 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 5100-5107 in August 1915.Originally built for the D&SL for the Rollins Pass route, they had problems negotiating the curving alignment and slipped because of their power, according to Drury (1993). Still they ran until the late 1940s, receiving Coffin feedwater heaters. When the D&SL was acquired by the D&RGW in 1947, these engines re-numbered 1220-1227. Most were dismantled in the 1950s. NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface. Superheating surface is an estimate based on a very similar Lima Pacific delivered to the MKT (Locobase 7083) in 1920.
|Principal Dimensions by Steve Llanso of Sweat House Media|
|Railroad||Denver & Salt Lake (D&SL)|
|Number in Class||8|
|Locomotive Length and Weight|
|Driver Wheelbase (ft / m)||15.75 / 4.80|
|Engine Wheelbase (ft / m)||32.92 / 10.03|
|Ratio of driving wheelbase to overall engine wheebase||0.48|
|Overall Wheelbase (engine & tender) (ft / m)||67.67 / 20.63|
|Axle Loading (Maximum Weight per Axle) (lbs / kg)|
|Weight on Drivers (lbs / kg)||232,000 / 105,234|
|Engine Weight (lbs / kg)||295,000 / 133,810|
|Tender Loaded Weight (lbs / kg)||178,000 / 80,740|
|Total Engine and Tender Weight (lbs / kg)||473,000 / 214,550|
|Tender Water Capacity (gals / ML)||8736 / 33.09|
|Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)||17 / 15.50|
|Minimum weight of rail (calculated) (lb/yd / kg/m)||97 / 48.50|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in / mm)||55 / 1397|
|Boiler Pressure (psi / kPa)||200 / 13.80|
|High Pressure Cylinders (dia x stroke) (in / mm)||26" x 30" / 660x762|
|Tractive Effort (lbs / kg)||62,684 / 28433.02|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||3.70|
|Firebox Area (sq ft / m2)||352 / 32.70|
|Grate Area (sq ft / m2)||70.40 / 6.54|
|Evaporative Heating Surface (sq ft / m2)||4224 / 392.42|
|Superheating Surface (sq ft / m2)||870 / 80.82|
|Combined Heating Surface (sq ft / m2)||5094 / 473.24|
|Evaporative Heating Surface/Cylinder Volume||229.13|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||14,080|
|Same as above plus superheater percentage||16,474|
|Same as above but substitute firebox area for grate area||82,368|