Invention and Engineering
A drag freight is a lengthy, slower moving, high-tonnage railroad train, often carrying bulk commodities such as coal or ore. Compared to "fast freight" trains, drag freight trains have a very low power-to-weight ratio, making these trains somewhat unpredictable on steep grades or hilly routes. This causes many dispatchers to be extremely conservative with how they handle drag freights, especially when they share lines with higher priority fast freights and passenger trains.
Economy of California.
Global cooling.
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