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 TB 55-1900-232-10
can control the payout of towline by making turns around the bitts. When enough line has been pulled out, the towline is
stopped off to the towing bitts with the towline passing over the stern roller. Speed is then built up slowly until the target
is towing steadily.
4-2.3.4 At the Firing Range. The towing ship times its arrival at the firing range long enough before the exercise begins
to allow time to stream the target. Slowing to about 4 knots and payout line at 150 feet per minute is the safest way to
stream. The tow hawser can be recovered at the maximum speed of the capstan or traction winch used. Hawser payout
typically proceeds at 40 to 60 feet per minute.
4-2.3.5. Turns. With the Williams Target Sled, turns can be made in one increment, depending on the weather, by using
a small amount of rudder so as to have about a 1,000-yard diameter turning circle. When making turns, the target must
be kept aft of the towing ship's beam, preferably broad on the quarter. When proceeding on a circular course, the
target's tendency to capsize depends on the speed of the tow, length and depth of towline and the sea state and heading
relative to the wind.
The characteristics of turns to windward differ from those of turns to leeward. In turning into the wind, the target screen
area acts as a mainsail and holds the target away from the turn, requiring an increased rudder angle and giving a smaller
transfer with a slightly greater advance. In turning to leeward, the sail effect propels the target toward the inner part of
the turn, requiring less rudder and performing a greater transfer with less advance. In all turns the target acts as a sea
anchor, making a small tactical diameter while the ship turns around the target with a larger tactical diameter.
Turns with the current increase transfer, and turns against the current reduce transfer. The advance in all turns is small.
To keep the towline tension low and to avoid capsizing the tow, keep the rudder angle as low as is practical. A mean
rudder angle of 12 or 13 degrees is satisfactory. A good practice is to make the turn in small increments, steadying up
until the target is directly astern before going to each new increment.
4-2.3.6 Concluding the Exercise. When the exercise is over, the towline is heaved in to shorter stay for the tow home
or brought up short to permit the target to be lifted aboard. The methods of heaving the line vary with the towing ship's
equipment. For example, combatants use their capstans to heave the towline, MSOs can use one drum of the sweep-
wire winch, and salvage ships use their capstans or traction winch. Immediately on bringing the towline aboard, it should
be faked on deck or spooled on a reel. Significant time must be allowed to bring the hawser in at even maximum
capstan speed. Entering port, the tow can either be brought alongside, brought to short stay or lifted aboard. The use of
riding lines which have been stopped off on the tow hawser during streaming contribute to the ease of bringing the sled
alongside. For leaving and entering port, some ships have preferred two-blocking the bow of the sled against their stern.
When firmly snugged into position and adding riding lines, this method allows good maneuvering.
4-2.4 SPECIAL PROCEDURES.
4-2.4.1 Passing the Target to a Combatant Ship. It is sometimes necessary to exchange towing ships during an
exercise. The methods described in Paragraph 4-2 3.2 for delivering a target to a towing ship do not apply on the open
sea.
WARNING
Most casualties in passing a tow occur because the ships do not maintain a steady course or speed, or because
the towing ship releases the tow before the other ship is ready to accept the strain.
4-3
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