Grade

Percent of ruling grade = 1.5

Curvature

Sharpest or ruling curve 100

To use the formula for CTL given in the preceding paragraph, you

must first find values for DBP, W, RR, GR, and CR.

a. Drawbar pull. Your locomotives have a continuous tractive

effort of 36,000 pounds from which 20 pounds per ton of total

locomotive weight must be subtracted to get DBP. Thus:

b. Weather factor. In table III, you find that between 11 and

20 F. a locomotive loses 20 percent of its hauling power;

therefore, the weather factor is 80 percent. This means that the

locomotive is able to exert only 80 percent of its normal hauling

power.

c. Rolling resistance. In table II, you find that the rolling

resistance is 7 pounds per ton of train on a track rated fair to

poor. The value you must use for RR then is 7.

d. Grade resistance. Paragraph 2.7 explains that grade

resistance is equal to 20 pounds per ton of train multiplied by the

percent of ruling grade, which is 1.5 for your railway division.

When you multiply 1.5 by 20 you get 30the value for GR.

e. Curve resistance. Curve resistance is found, as explained in

paragraph 2.8, by multiplying 0.8 pounds per ton of train per degree

of curve. In this example, 0.8 multiplied by 100 gives you a CR

value of 8.

f. Using the formula. Substitute the values you have found for

the factors in subparagraphs a through e in the formula for GTL as

follows:

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