Naval towage vessels and commercial tugs are being built by two different shipyards in the US
Gulf Island Shipyard has laid the keel for a second Navajo-class towing, salvage and rescue vessel for the US Navy. The Navajo-class vessels will provide oceangoing towage, salvage and rescue capabilities to support fleet operations.
These capabilities are currently provided by three T-ATF 166 and two T-ARS 50 ships, several of which will reach the end of their expected service lives later this year.
Navajo-class ships will have 557 m2 of deck space for embarked systems, will be 80 m long, have a beam of 18 m and can carry a load of almost 2,000 tonnes.
Gulf Island Shipyard will name this second vessel, USNS Cherokee Nation. It is progressing with the first of these vessels, USNS Navajo, and is undergoing detailed design and construction for USNS Saginaw Ojibwe Anishinabek.
On the US west coast, Diversified Marine Inc is building a second tug with integrated low-emissions propulsion for Brusco Tug and Barge.
This vessel is being built to a Robert Allan RAmpart 2500 design with full Caterpillar Marine propulsion. This tug will have propulsion that complies with US Environmental Protection Agency (EPA)’s Tier 4 emissions requirements.
This includes two Cat 3516E main engines that develop 2,240 kW at 1,800 rpm. These drive Caterpillar MTA 627 azimuth thrusters with 2.7-m diameter propellers providing this tug with bollard pull of around 84 tonnes. Caterpillar is also supplying Cat C7.1 generator sets that produce 118 kW of electrical power.