Saturday, November 7, 2009

Tug Boats, Part 1: Types of Tugs

Some of the hardest-working boats in the world are tugboats and towboats (I'll call them "tugs" here for convenience sake, with apologies to the many towboat crew who hate to be lumped in this category). A tug is any vessel that assists another in maneuvering. The other vessel may be unable to maneuver at all, like a barge or a vessel with mechanical problems, or just need assistance in a narrow channel or alongside a berth, like a large container ship coming into port. There are several different types of tugs:

Commercial assistance towboats. These tend to be small craft designed to help out other small craft with mechanical problems or that have just run out of fuel. They are the sea-going equivalent of Triple A. Although they may be available on a call-out basis in some harbors, many also offer a membership, again like Triple A. The Sea Tow franchise is the most visible and well known of these outfits.

Harbor tugs. Any vessel who's job it is to help a large ship get into out of an anchorage or berth in a harbor. This is the kind of vessel most people think of when they think, "tug boat." These tugs are very powerful for their size to, in effect, provide an additional engine for the large ship they are assisting. Harbor tugs tend to have lots of cushioning, especially on the bow, so thy can get right up against other vessels. They pull by attaching themselves to the vessel using wire cable or strong fiber line. Pictured above on the left is the just-launched Seaspan Resolution, which serves the harbor in Vancouver, British Columbia.

Seagoing tugs. These tugs meant for ocean service may be seen hauling a barge of supplies to Alaska or islands in the Pacific, or towing a large ship from one port to another. The picture in the center above is a seagoing tug towing a ship through the Panama Canal.

ITBs or "integrated tug and barge units." This type of tug is designed to fit into a notch at the stern of a barge, in effect making the whole tug/barge combination a single vessel.

River towboats. Flat on the bow, these boats push barges ahead. Their design makes them unsuitable for sea-going duty, but perfect for the complicated navigation and close-quarters maneuvering required on rivers. Pictured on the right above is a river towboat pushing several barges ahead on the Columbia River.

Specialized tugs. Some tugs are designed for specific jobs, such as firefighting, escorting oil tankers, or towing MODUs (floating oil rigs).

1 comment:

  1. I am interviewing veterans of the various wars for a book to be given to the veterans and a copy placed in our library in the retirement home we live in. Your explanation of the tugs is helpful as one of our veterans spent time aboard a sea going tug during the Korean War. Since we are all in our 80's plus, these tidbits I find on the net are very helpful. Thank you for your information.