Suderman & Young completes series of Z-Tech tugboats

Mercury Robert Mihovil Photo
Mercury Robert Mihovil Photo
Mercury was the fifth in a series of five tugboats Gulf Island Shipyards built for Suderman & Young.

Suderman & Young Towing of Houston has taken delivery of the final two vessels in its five-vessel order from Gulf Island Shipyards.

The 98.5-by-42-foot Gemini and Mercury are built to the Robert Allan Ltd. Z-Tech 30-80 design. Tugs in the series deliver more than 80 metric tons of bollard pull and can hit 13 knots at full throttle.

Gemini was completed in April 2020, while Mercury entered service in fall 2020. The two tugboats are powered by twin 3,386-hp Caterpillar 3516E Tier 4 engines paired with Schottel SRP 510 FP z-drives. Electrical power comes from two John Deere 6068AFM85 generators producing 125 kW each.

Mercury is equipped with two 6,200-gpm FFS fire pumps, each driven by a Cat C18 engine, that deliver water to two FFS monitors. Its ship-handling winch on the bow is a 100-hp Markey DESF-48A-100 unit.

“We included this particular winch on Mercury to give us additional capability when assisting our customers in near-shore environments where increased dynamic sea states are encountered,” Suderman & Young President Kirk Jackson said.

Gemini is outfitted a little differently. It does not have the same off-ship firefighting capabilities, and it is equipped with a slightly different Markey DEPCF-52 winch on the bow. The robust unit is plenty suited for handling large containerships and tankers calling on Texas ports regularly.

Tugboats in this series have an ergonomically designed wheelhouse with Furuno navigation electronics and Icom VHF radios. Tanks on the tugs can hold more than 42,000 gallons of fuel. Schuyler Cos. fendering protects critical sections of the tugboats during assist jobs.

George M.

Bay-Houston Towing of Galveston completed its own five-vessel order of Robert Allan Ltd. Z-Tech tugboats from Gulf Island Shipyards with the arrival of George M. in January 2021.

The 98.5-by-42-foot George M. is a sister tug to Mark E. Kuebler, the first Z-Tech 30-80 tug in the series delivered in late 2018. The propulsion package consists of two 3,386-hp Caterpillar 3516E Tier 4 engines paired with Schottel SRP 510 FP z-drives with 110-inch propellers. Two John Deere engines provide electrical power. Bollard pull exceeds 80 metric tons.

“We are extremely proud of the fifth Z-Tech tug built by Gulf Island Shipyards LLC for Bay-Houston Towing Co.,” Mike Fitzpatrick, president and CEO of Robert Allan Ltd., said in a prepared statement. “Of all the vessels built to our design internationally, the ones we are most proud of inevitably involve a high-quality builder and a knowledgeable owner (who) fully understands the way their vessels need to operate. We most definitely had both for the construction of these five tugs.”

George M. has two 6,200-gpm FFS fire pumps and two forward-facing FFS monitors driven by two Caterpillar C18 engines. The hawser winch on the bow is a 75-hp Markey DEPCF-52 unit designed to work big ships calling on the Texas coast. The wheelhouse has modern Furuno electronics, and fendering form Schuyler Cos.


Diversified Marine completed the second of two 128-foot oceangoing tugs for Sause Bros. of Coos Bay, Ore.

The 4,000-hp Geronimo is a sister to Apache, delivered in mid-2019 using a design created by Sause Bros. engineers.

Propulsion on the new tugboat series comes from two 2,000-hp MTU 16V 4000 Tier 3 engines turning 104-inch propellers in nozzles through Reintjes WAF 873 reduction gears. Two John Deere engines drive 99-kW Marathon generators.

The towing winch on the stern is a Rapp TOW-22031 carrying roughly 2,600 feet of 2.25-inch wire, while the bow is equipped with a Rapp TOW-4002-BB winch. Schuyler Cos. provided the hull fendering.

Geronimo, like Apache before it, is an updated version of Sause Bros.’ proven Mikiona class of oceangoing tugboats built in the late 2000s. The new vessels feature modern electronics, more powerful engines and enhanced crew comforts compared to earlier tugs in the class.

Cape Henry and Cape Fear 

Vane Brothers welcomed two more Sassafras-class tugboats to its East Coast fleet over the past year.

The company, based in Baltimore, took delivery of the 94-by-32-foot Cape Fear in October 2020, followed by Cape Henry in April 2021. Chesapeake Shipbuilding & Naval Architects of Salisbury, Md., built the tugs based on a model bow design developed by the late Frank Basile.

The 3,000-hp tugboats are the 15th and 16th vessels in the series, all built in Maryland.

The newbuilds are powered by twin Tier 3 Caterpillar 3512 main engines turning 89-inch propellers through Twin Disc gears. Electrical power comes from three John Deere gensets. JonRie supplied the Series 500 hydraulic towing winch and Series 421 30-hp electric marine capstan. M&M Bumper Service provided the hull fendering.

The wheelhouse on Cape Henry and its sister tugs has a 38-foot height of eye. The space is equipped with Simrad navigation electronics and Icom radios.

“Vane Brothers remains committed to investing in thoughtfully crafted vessels that are highly efficient and reliable while also capitalizing on crew safety and comfort,” Vane Brothers President C. Duff Hughes said in a prepared statement. “Just like her smartly built predecessors, Cape Henry has been designed to deliver peak productivity when paired with the Vane fleet of coastwise tank barges.”

Tugboats in this series are typically paired with 30,000- to 35,000-barrel tank barges engaged in the bunkering trade.

Vane Brothers, which has steadily upgraded its fleet over the past decade, also plans to add two more 3,000-hp Salisbury-class pushboats to its lineup, bringing the total to four. The third boat in the series, Rock Hall, is slated for delivery this year. 


Great Lakes Towing Co. took delivery of the fifth 2,000-hp tugboat in a series of up to 10 vessels built at the Cleveland-based company’s shipyard along the Cuyahoga River.

The 64-foot Wisconsin is a sister tug to Cleveland, Ohio, Michigan and Pennsylvania, built over the past four years using the Damen Stan Tug 1907 ICE design. It entered service in November 2020 and performed its first ship-assist job early the following month. It is based in the consolidated ports of Detroit, Mich., and Toledo, Ohio.

Propulsion comes from two 1,000-hp MTU 8V 4000 Tier 3 engines paired with 71-inch propellers in nozzles through Twin Disc MGX-5321 reduction gears. Tugs in this series produce 30 tons of bollard pull.

Wisconsin is equipped with a diesel-electric FlexaDrive system from Logan Clutch that uses two 65-kW John Deere/Marathon gensets to produce electrical power for motors installed on the reduction gears. Those motors can move the gears to turn the propellers.

The hybrid system delivers multiple benefits, including a 200-hp boost when maximum power is needed. It allows the tugs to transit to or from jobs without the main engines, which reduces fuel consumption, emissions, noise and maintenance.

Tugs in the series are equipped with Furuno navigation electronics and Icom radios. The aft deck has a sturdy towing bitt and a 15-hp capstan. Schuyler Cos. supplied the hull fendering.

Great Lakes Shipyard has begun construction of the sixth and seventh tugboats in the series. The sixth boat, for now known as Hull 6506, is scheduled for delivery later this year. Hull 6507 is expected in mid-2022.

By Professional Mariner Staff