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 TB 55-1900-232-10
SECTION III
4-3 INLAND BARGE TOWING.
Barge towing supports Navy logistic requirements. The basic techniques for inland barge towing are almost identical for
harbor tugs as well as towing ships. The principles of alongside towing and handling become part of the open-ocean tow
in making up, streaming and entering the harbor. The Boatswain's Mate First Class and Chief Rate Training Manual
(Ref. 8) provides a thorough discussion of inland barge towing in its most usual fashion, alongside. Understanding the
basic principles set forth therein will enable personnel on board the oceangoing tug or salvage ship to approach inland
towing in a professional manner.
SECTION IV
4-4 TOWING IN ICE.
Arctic operations make it necessary to tow in ice, and it may also be necessary to recover a ship whose steering and
propulsion equipment are not functional. An icebreaker may be required for breaking through heavy ice, but Navy ocean
tugs can tow in broken ice. U.S Coast Guard icebreakers equipped with towing machines now are being
decommissioned.
Although Navy ARS 50 and T-ATF Classes were built to modified ice strengthening rules, their Kort nozzles may make
them less suitable for heavy ice operations than the ATS 1 and ARS 38 Classes. The ATF 76 Class is not suitable due to
its light hull construction.
If possible, during tows of long duration in ice conditions, the catenary should be adjusted so that the chain bridle, or
chain pendant, enters the water at the towed vessel and prevents the hawser coming into contact with the ice. After a
period of exposure to ice, the hawser will wear and chafe. This item is addressedinATP-15 Arctic Operations (Ref. 9).
4-4.1 TOWING METHODS. The tow should be close to the tug's stern to keep the ice passage open ahead of the tow.
4-4.1.1 Short-Scope Method. Paragraph 4-4 1.2 discusses the saddle method of towing in ice. Navy ocean tugs
should utilize the short-scope method since they have no saddles. Even for towing ships that do have saddles, the
saddle method may not be practical for towing a high-bowed or bulbous-bowed ship Such ships can be towed at short
scope by the conventional method, using both anchor chains and a towing bridle to provide extra weight in the short
scope. A scope of 150 to 300 feet can be maintained. The tow's rudder should be used, if possible, to keep the tow in the
tug's wake. Occasional kicks from the tow's propeller may be necessary to augment the rudder's force. The tug's
propeller wash should keep the tow from riding up on the stern; if it does not, the propeller of the tow should be backed, if
possible.
4-4.1.2 Saddle Method. If the short-scope method of towing in ice is not feasible, a variation of the saddle method
formerly used by icebreakers may be possible for tow ships having strong, broad sterns. The tow is brought up snug
against the tug's stern, using extensive chafing gear, heavy fenders and puddings. The towline is attached in the normal
fashion The towing machine should be in the automatic mode to prevent the towline from parting if the ships pitch or
surge Two mooring lines can also be passed from the tug's quarter-bitts to the tow's forecastle bitts to help keep the tow
following fair. The tow's engines can be used; however, if the tow begins to sheer or yaw badly, it should slow at once
until it is again under control.
A fire hose should be kept ready at the saddle when using the tow's engines; friction may cause fires in the chafing
material. Of course, the saddle method cannot be used on tows with sharp prows, bulbous bows or any other
protuberances which can interfere with the tug's propellers and rudders.
4-5
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