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

per trip into several components, e.g., make tow, break tow, locking,
etc. But some tow delays were best treated by lumping them together
into a single category which was called "miscellaneous delays."
These miscellaneous delays were those due to weather, running aground,
. •
waiting for bridges, etc. In the case of rail, for a given level of
traffic, the delays encountered en route are similar to those in the
miscellaneous category for barge tows, i.e., there are a large number
of random and independent delay-causing factors which may be combined
for treatment. However, train delays are also related to congeition
en route.
In the next subsection, a brief discussion of delay-estimating •
procedures is presented. Some data obtained from a railway are alio
discussed to give an idea of the magnitude of linehaul delays.
Apart from delays en route, trains are detained at terminals for in- '
spection and assembly. Although this category of delay will not be
discussed below, several studies - of yard operations are available, 13
the results of which could be incorporated into the rail linehaul
process function in the same manner in which make and break tow de-
lays were incorporated into the tow linehaul process function.
Delays en Route. The time in hours, T f , required to travel the
distance D miles at cruising speed of V i miles per hour was given
in Equation (3.4) as
T f = D/V f . ' (5.30)
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