Figure 7-13.--Typical bow chafing chain arrangement for being towed.
which is used for dropping the tow in case of
line is attached to the shot line, reducing the weight on
emergency. The other end of the chafing chain is fair-
the shot line while the messenger is passed to the
led through a closed chock on the stern. A typical
receiving ship. The hawser and messenger are faked out
arrangement is shown in figure 7-14. Since it is logical
and stopped off to a strongback, with turns of 21-thread
to assume that the reason a ship has to be towed is
line running over a chop block to provide constant
because it has lost power, the rigging arrangement
control while the hawser is paid out. These stops are cut
aboard the ship to be towed must be laid out so no power
on command as the hawser pays out. A retrieval line is
assistance is required. Therefore, practice operations
connected to the anchor chain end of the towing opera-
should be performed with the towed ship using no
tion to retrieve the towing hawser. The same procedure
is followed on the towing ship, except that the pelican
power equipment.
hook is rigged to the hard point, and the chafing chain to
Towed-Ship Rigging Procedure
the pelican hook, fair-led out the stem chock. You will
The towed ship rigs for being towed by breaking the
notice that we have referred to the ship to be towed as
anchor chain inboard of the swivel shot. The anchor not
being the provider of the rig. Which ship ultimately
in use is secured in the hawsepipe by a chain stopper and
provides the initial hawser is a command decision, and
a preventer made of wire. The wildcat brake is set up.
circumstances will be different in each case.
When the chain pipe has a compressor, it is used to keep
the chain from falling back into the chain locker; when
there is no compressor installed, a bar through the chain
and across the chain pipe can substitute for the
compressor. The chain is then moved over in alignment
with the bow chock It will be hauled through the bow
chock later by the towing hawser as a strain is taken on
the hawser by the towing ship. The connector fittings
are standard rigging and detachable links of the size of
chain being used. The towing hawser is either wire,
whose size and length satisfy the ship's plans, or
synthetic hawser 600 feet long. Attached to the hawser
is a messenger made up of 100 fathoms of 3-inch line
and 50 fathoms of 1 1/2-inch line. (For a lo-inch
circumference or larger hawser, use the 4-inch in place
of the 3-inch.) Two 100-fathom lengths of 6-thread or
9-thread line are attached to the 1 1/2 line and run
Figure 7-14.--Typical stern chafing chain arrangement for
outboard on both sides of the ship. Then the 6-thread
towing.
7-11
