The US Navy has accepted the delivery of the first of 25 tugs from Washington-based Modutech Marine.
Designated as Work Boat Medium, the first was delivered last month. The others will follow in regular deliveries through to December 2019.
The 9.1-metre by 4.5-metre vessels (with 1.6-metre draughts), were designed by Seattle-based naval architect firm Hockema and Whalen and Associates.
Powered by a pair of Cummins diesel engines each delivering 212kW continuous duty, they provide a 7.9-tonne bollard pull. Between jobs, the boats are capable of speeds up to nine knots.
On deck, a 181kg davit can be moved to port or starboard mounts as required.
A pair of Bloom deck winches are mounted forward, port and starboard to complement a pair of cheek blocks mounted alongside the pilothouse for making up to a barge with the push knees.
Wide side decks provide a safe workspace for the deckhand.
Heavy bollards are mounted on both sides for mooring and for working barges or other equipment on the hip.