Q2 Z2,(Q2) Z2(Q2) - Institute for Water Resources - U.S. Army

delay time would be simply the arithmetic average delay time over a
sample of train trips. This, of course, ignores congestion and
would relate to a specific route only.
In order to get an idea of the magnitude of linchaul delays, a
sample of 100 unit-train movements was obtained. These data all re-
late to the same origin-destination combination: a one-way distance
of 227 miles. Information on the composition of each train was ob-
tained, specifically: (1) number of cars, (2) tare weight of cars,
(3) loaded weight of cars, (4) number of axles on each car, (5) num-
ber of locomotive units, (6) horsepower of each locomotive unit, and
(7) number of axles on each locomotive unit. Detailed terrain anal-
ysis of the route was made by the railway; it was decided that there
was no appreciable gradient or curvature along the route. Given
this information--train characteristics and route characteristics--
it was possible to determine the speed of each sample train from the
solution to Equation (5.24) above. Applying Equation (5.24) to each
of the 100 data points in turn yielded 100 predicted speeds V i and,
by Equation (5.29), 100 predicted trip times, Ti. These were then
subtracted from the observed trip times supplied by the railway.
The result in'each case was an estimate of delay time en route. It
should be stressed that no terminal time was included in these ob-
servations; therefore, assuming the predicted times are correct,
deviations from predicted trip times are due to delays en route in-
volving slow-downs as well as stops. The results are shown in
Table 5.1.
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