A tugboat or tug is a marine vessel that manoeuvres other vessels by pushing or pulling them, with direct contact or a tow line. These boats typically tug ships in circumstances where they cannot or should not move under their own power, such as in crowded harbors or narrow canals, or cannot move at all, such as barges, disabled ships, log rafts, or oil platforms. Some are ocean-going, and some are icebreakers or salvage tugs. Early models were powered by steam engines, which were later superseded by diesel engines. Many have deluge gun water jets, which help in firefighting, especially in harbours.
A mooring is any permanent structure to which a seaborne vessel may be secured. Examples include quays, wharfs, jetties, piers, anchor buoys, and mooring buoys. A ship is secured to a mooring to forestall free movement of the ship on the water. An anchor mooring fixes a vessel's position relative to a point on the bottom of a waterway without connecting the vessel to shore. As a verb, mooring refers to the act of attaching a vessel to a mooring.
Anchor Handling Tug Supply (AHTS) vessels are mainly built to handle anchors for oil rigs, tow them to location, and use them to secure the rigs in place. AHTS vessels sometimes also serve as Emergency Response and Rescue Vessels (ERRVs) and as supply transports.
A bollard is a sturdy, short, vertical post. The term originally referred to a post on a ship or quay used principally for mooring boats. In modern usage, it also refers to posts installed to control road traffic and posts designed to prevent automotive vehicles from colliding or crashing into pedestrians and structures.
The tack of a square-rigged sail is a line attached to its lower corner. This is in contrast to the more common fore-and-aft sail, whose tack is a part of the sail itself, the corner which is secured to the vessel.
Bollard pull is a conventional measure of the pulling power of a watercraft. It is defined as the force exerted by a vessel under full power, on a shore-mounted bollard through a tow-line, commonly measured in a practical test under test conditions that include calm water, no tide, level trim, and sufficient depth and side clearance for a free propeller stream. Like the horsepower or mileage rating of a car, it is a convenient but idealized number that must be adjusted for operating conditions that differ from the test. The bollard pull of a vessel may be reported as two numbers, the static or maximum bollard pull – the highest force measured – and the steady or continuous bollard pull, the average of measurements over an interval of, for example, 10 minutes. An equivalent measurement on land is known as drawbar pull, or tractive force, which is used to measure the total horizontal force generated by a locomotive, a piece of heavy machinery such as a tractor, or a truck,, which is utilized to move a load.
Colombo Dockyard PLC (CDPLC) is a ship building company in Sri Lanka and it is based in Colombo. It has built both military and civilian vessels for both local and overseas clients.
The Ville-class tug are a class of harbour tugboats employed by the Royal Canadian Navy.
An emergency tow vessel, also called emergency towing vessel, (ETV) is a multi purpose boat used by state authorities to tow disabled vessels on high seas in order to prevent dangers to man and environment. The disabled vessel is either towed to a safe haven or kept in place against wind and current until commercial assistance by tug boats has arrived on site or until it has been repaired to the extent of being able to manoeuvre on its own. The need for ETVs as a preventive measure has arisen since the number of available commercial salvage tugs was reduced while potential dangers from individual vessels have increased. E.g. Spain has fourteen, Turkey has eleven, Germany operates eight, Norway has seven, France has five, Sweden three and the Netherlands, Poland, South Africa, Iceland and Finland each have one official emergency tug boat. Australia also operates emergency response vessels. The United Kingdom's four strong ETV fleet was to be disbanded in September 2011 due to budget cuts but the two vessels operating in Scottish waters received an extension of contract until the end of 2011.
John Bollard may refer to:
The Anand class tugboats are a series of service watercraft built by Goa Shipyard Limited, for the Indian Navy. Tugs of this class have a 6-tonne bollard pull.
The Gaj class offshore tugboats are a series of two auxiliary watercraft built by Garden Reach Shipbuilders & Engineers Ltd., Kolkata, for the Indian Navy. The vessels in the class are Indian Navy's biggest tugboats and can be used for towing aircraft carriers.
The Bahadur class tugboats are a series of service watercraft built by Goa Shipyard Limited, for the Indian Navy. They have a rated bollard pull of 10 tonnes.
The RPC12 is a type of harbour tugboat operated by the French Navy. They utilise Voith propulsion to develop a 12-tonne bollard pull.
Folly Bollards is a series of outdoor 1998 bronze bollard sculptures by Valerie Otani, installed along Southwest Main between Broadway and Park in Portland, Oregon, United States.
The IRS class of tugboats are a series of Bollard pull tugboats built by Hindustan Shipyard Limited, Visakhapatnam, for the Indian Navy.
A messenger line or just messenger is relatively light cordage used to pull a heavier cable across a gap or through a tube or duct. The term is also used for a line used to pull or lower a package along a downline or jackstay.
The United States Navy's 19BB (Barrier Boat) was built by Chuck's Boat and Drive of Longview, Washington in 2002 to deploy and maintain port security booms surrounding Navy ships and installations in port. The first boat of the 13-boat order was delivered in January 2003.
