Case Study: US Navy Work Boat Medium achieves versatile towing performance with Cummins QSL9-powered tugboats

Modutech Marine’s Work Boat Medium

The US Navy Work Boat Medium program needed compact, efficient support tugs to handle heavy pushing and general harbor work around its ports and facilities worldwide. To meet this need, the Navy worked with Cummins and Modutech Marine on a 30-by-15-foot tug design built to perform multiple support roles reliably.

Cummins supplied a pair of QSL9 diesel engines, each rated at 285 HP continuous duty, paired with ZF W325 gears and nozzled propellers. The resulting 570 HP package delivers a 17,500-pound bollard pull and about nine-knot top speed, giving the Navy a versatile and capable workboat with features such as deck winches, a davit, towing bitt, and heavy-duty fendering.