a. Doubleheading locomotives. If there are enough 0440
dieselelectric locomotives on the 2d division, they can be double
headed. Since diesels can be doubleheaded without loss of hauling
power, the GTL can be doubled as can the NTL. With the same TD, the
NDT is adjusted to 4,347 short tons. As a result, the EDT is
Since the 2d division would still be the most restrictive of
the three divisions with an NDT of 4,347 short tons, the EDT for the
railroad would also be 4,347 short tons.
b. Increasing the number of passing tracks. If you cannot
doublehead locomotives but you can increase the number of passing
tracks by constructing new ones at proper locations, from 6 to 8
miles from other passing tracks, the train density can be increased.
For example, by constructing 6 new passing tracks, thereby increasing
the TD to 12, the NDT for the second division can be raised to 3,732
short tons. Again the EDT is correspondingly raised.
The adjusted NDT of 3,732 short tons for the 2d division would
be the EDT for the railroad, because this division would still be the
most restrictive of the three divisions.
To determine the tonnage capacity of a rail line, a planner must
know the work capacity or hauling power of the locomotives he