25
(5) Using the formula. Now that you have values for all of the
unknowns, substitute them in the formula for CTL, as illustrated in
d. Net trainload. The fourth step is to find the net trainload
(NTL) as explained in paragraph 2.12. Since NTL is 50 percent of
GTL, the NTL for this division is 419 short tons.
837 x .50 = 418+, or 419 short tons
e. Train density. Now, for the fifth step, determine what the
train density (TD) is for the division. Using the formula presented
in paragraph 2.13b and the information in paragraph 2.17a, you have
values for all of the unknowns except average speed (S). Since the
track is rated good to fair and the percent of ruling grade is 1.5,
table IV shows that an average speed of 10 mph should be used.
Substitute this value in the formula and make your computations for
TD as follows:
f. Net division tonnage. Now that you know the NTL and the TD
for this division, the final step is to find the net division tonnage
(NDT) by multiplying the two values NTL x TD:
419 x 15 = 6,285 STON
If you do not run any passenger trains over this division, you can
move 6,285 short tons over it.