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 TB 55-1900-232-10
increase in towline scope. When tug and tow are dead in the water, the towline catenary will have a tendency to draw the
tug and tow together. The same situation can occur between two tandem tows. In an emergency, in shallow waters, it
may be possible to anchor the tug and tow by letting the towline come into contact with the bottom.
3-8.6 SINKING TOW.
a. Flooding, structural damage, shifting of ballast or cargo and other events may degrade the tow's stability, and in an
aggravated condition of stability, the tow may be in danger of sinking. Prompt action is necessary to save the tow and to
ensure the safety of the tug
b. It is vital to monitor the condition of the tow during transit, trim, list, roll period, seakeeping and draft are monitored
from the tug or by the riding crew if on board. Upon noting an irregularity, a boarding party should be dispatched, if
possible, to investigate and correct the deficiency on board the tow. If the material condition of the tow is so deteriorated
that sinking is likely, the tug should consider beaching the tow or paying out the towline to the last few wraps to prepare to
slip it.
c It may be impossible to disconnect on board the tow. This will necessitate cutting or slacking the towline. Excessive
strain placed on the tug as the tow sinks can cause great damage and seriously endanger the tug before the tugline parts.
Rather than endangering the tug, it is considered good seamanship to slip the towline from the drum and to provide some
method of cutting the hawser if it fouls on the tug. Cutting torches or wire cutters (mechanical or explosive) should be on
standby. If time permits, carpenter stoppers or other devices should be rigged.
d. Use of educators operating from a floated 2 1/2-inch fire hose may be feasible in dewatering.
3-8.7 BEACHING A SINKING TOW.
a. When towing a casualty or a tow where the material condition has deteriorated so as to make sinking probable,
beaching the tow may be the best possible action to save it. Permission to beach should be obtained from the cognizant
authority when feasible. The decision to beach the tow should be made by immediate message or voice communications
when feasible. Significant time may be required to steam the distance to a suitable site. If pumps are on board the tow
and damage control procedures are employed, the tow may be kept afloat for days before beaching. The decision to
beach the tow is operational and should be based on an assessment of conditions. Many times the beaching of tows has
saved them. Indecision has caused tows to sink.
b. If available, a beach with a smooth, gradually sloping bottom should be selected as the beaching site The tow should
be grounded with the bow toward the beach. It is important to prevent the tow from broaching and sustaining additional
structural damage through excessive hull loading. Flooding the tow can prevent it from broaching or going further
aground. The ship should be set down hard enough so that it will not be too light and, consequently, broach at high tide It
should be assumed that in time the tow will be pulled off; however, this does not eliminate the need for securing it
properly and thus preserving it until it is extracted from the beach. It may be impossible to locate a smooth beach in
time. Rocky shores, with breaking surf, should be avoided. Potential loss of the tow plus imminent danger to the tug
exist in shallow, rocky waters. In order to put the tow on the beach bow first, the tug's assistance may be required. If the
water is sufficiently deep, the tug can tie up alongside in the lee of the tow and take the tow in. The alternative of
allowing the tow to drift onto the beach should be avoided. Danger to the tug is always an important consideration.
Assistance from a small, shallow-draft harbor tug may be available
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