The ETT gives engine ratings for the K-27 class on the Silverton branch. It shows a single K-27 capable of handling 315 tons, Hermosa to Silverton, and 800 tons Silverton to Durango. Looking at folio diagrams, and the report posted by Jimmy Blouch, it would appear that Train 461 was near the maximum for a single K-27, right in the range of 313 tons. Southbound Train 462 has nine more loads. Possibly concentrates? The southbound train would have been about 612 tons, well within the rating for a single K-27.
CVM
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