boiler due to the draft, and if any flues in the boiler are leaking, the loss of draft on the fire is much harder to work around than on the K-36 locomotives. Firing while the engine is working hard is done with a large "heel" pattern, generally with as little coal on the flue sheet as possible, and gradually sloping the fire bed towards the door sheet to the height or higher than the firedoors. This results in the draft being forced through the fire bed in the thinner areas towards the flue sheet, which usually is hindered by the lack of draft between the grates and the arch brick. New firemen sometimes have a hard time learning this, because the art of "reading" a fire takes time to learn and the amount of time working on the K-28 class locomotives is much-reduced compared to the railroad's usual K-36 workhorses, which have a larger firebox and are more forgiving in technique. Out of the original ten only three 470s remain, and all are owned and operated by the D&SNG. The other seven were requisitioned by the United States Army in 1942 to be used on the White Pass & Yukon Route in Alaska during World War II. They were later dismantled for scrap in 1946. Locomotives 473, 476 and 478 operated on many parts of the D&RGW. Engine 473 served frequently on the Chili Line that operated between Antonito, Colorado and Santa Fe, New Mexico, until the line was abandoned in 1941. 476 and 478 saw an extensive service on the San Juan passenger train, which ran between Durango, Colorado and Alamosa, Colorado until 1951. 473, 476 and 478 operated on the Silverton Branch from the 1950s through 1980 and are still in service today. In July 2015, the D&SNG and C&TSRR had announced an engine-trade propasal by which the 478 would go to Chama, New Mexico, and, in exchange, the D&SNG would get K-36 class No. 483, which had not seen operation in several years. Since the swap failed to go through, the D&SNG announced in June 2016 that it was going to restore 476 to operating condition and place 478 in the museum. No. 473 has been converted to an oil burner and is operational. No. 476 has been converted to an oil burner and is operational. No. 478 is placed on display in the D&SNG Museum awaiting