New ship-docking tug exhibits agility in tight corners

"You are pulling this thing off like it was nothing," came the pilot's voice over the VHF.

"Well that was at 1,200 rpm," responded Capt. Bob Olson, skipper of the new ship-docking tug Shuswap.

The 3,200-hp docking tug Shuswap turns the car carrier Hyundai No. 103 in the Fraser River. (Alan Haig-Brown photo)

"What have you got left?" asked the pilot.

"I can take it up to 1,600 rpm," replied Olson, indicating the boat had lots more pulling power.

Delivered in June 2011, the tug, the first for the newly-formed Samson Tug Boats Inc., is quickly gaining a reputation amongst the pilots as a handy assist boat on British Columbia's Fraser River. With several berths serving car transport and smaller bulkers and container vessels, the river has a limiting draft of about 38 feet and some of the piers are in confined areas. This led to the adoption of a design by naval architect A.G. McIlwain. The new boat is 58 by 28 feet with a 12.5-foot molded depth. Propulsion is by a pair of HRP/ZF6111WM z-drives powered by a pair of 1,600-hp MTU 12V diesels.

Compared with some of the big tugs in ports like San Francisco or Vancouver that can exceed 5,000 hp, Shuswap is not setting records in that world. But it is now the most powerful ship assist tug on the Fraser River. Perhaps even more importantly, its dimensions are an asset in working the tight spaces of the river.

Engineer Chris Stradiotti, rear, operates winch controls while Capt. Bob Olson guides the tug. (Alan Haig-Brown photo)

But it takes more than a good boat to handle a light car carrier with big windage in river currents. Olson has over 50 years of experience on the river and his partner Chris Stradiotti has nearly 40. Both men were born in homes on the river and can't recall when they were first on a boat. Stradiotti, the grandson of the founder of a well-known tug company, is praised by Samson Tug's managing director, Gordon Yahn, as an engineer "who lies awake nights thinking of how to build things."

Olson's Swedish grandfather was the steam engineer at one of the Fraser's early salmon canneries.

Designed primarily for use as a two-man day-boat, it has a stove and fridge in the wheelhouse serving as a galley and two bunkrooms in the forecastle permitting a three-member crew to live aboard. The controls in the wheelhouse allow for the engineer to operate the winch without getting in the way of the captain's maneuvering.

Olson is on the joysticks. The forecastle entry is between the consoles. (Alan Haig-Brown photo)

In mid-September, Olson and Stradiotti were tasked to assist the car carrier GMT Polaris into the Annacis Island car terminal. At 570 by 91 feet, this is not a large ship, but car carriers present special challenges to a docking tug. Even with a full cargo, they are relatively light. Polaris was drawing only 27.5 feet, but the ship has a huge slab side that allows for very little deck and even that is far above the waterline. More significantly, the ship's side can act as a sail. There are reports of these ships taking advantage of that sail area to gain significant fuel-savings when crossing the Pacific.

While the ship may have an advantage on an ocean crossing, it is not to be found in port. On this night there was no significant wind; but when there is, the task of turning a ship in a river current can be that much greater. The high sides and inaccessible decks make use of the recessed bollards in the ship's sides and stern virtually mandatory.

While Shuswap waited at the company dock, Stradiotti picked up the ship at 2055 using his iPad ship-tracker program. The ship was about eight miles downriver and making 13 knots. Stradiotti flipped between the ship-finder program, NavX and Navionics charts to keep updated on the ship's progress.

"I know a tug captain who navigated all the way from the Bahamas to Vancouver with an iPad," he declared.

Aboard the docking tug Shuswap, Engineer Chris Stradiotti explains the fabrication of extra lashing on the hawser to protect it from chafing. (Alan Haig-Brown photo)

This is not necessary on Shuswap as the vessel has a full suite of electronics and multiple screens to display navigation information.

Shuswap left the dock and began idling upriver toward the car terminal about two miles farther upstream. By the time the tug was passing under the Alex Fraser Bridge, the ship's running lights were showing up astern as the ship began to catch up with the tug.

At 2125 the ship's pilot, Capt. Bob Gibney called Shuswap to ask that its crew put a line up to one of the recessed bits in the high stern of the ship. Olson moved the tug into the stern and Stradiotti stepped out onto the foredeck. He had already slacked enough line off the winch to reach up to the main deck if the recessed bollard was out of reach. But he was easily able to step up on the tug's bow and drop the eye of the line over the upper of two recessed bollards. The tug's Markey winch is equipped with a render/recover system, but it was not required on this night.

Chris Stradiotti, in the engine room of Shuswap. The tug is powered by a pair of 1,600-hp MTU 12V engines. (Alan Haig-Brown photo)

The pilot asked for "half back" to slow the ship and the winch tension meter swung up to 25 tons with the tachometers showing 1,200 rpm.

The tug Westminster Chinook had been chartered by Samson Tug as the second tug on the job, and the pilot asked its crew to be ready to push on the ship's forward shoulder. Stradiotti stepped into the wheelhouse, and using the winch control on the console, took up the extra line while Olson, following the pilot's request, swung the tug to 90° on the stern to begin swinging the ship in the river so that it could be docked starboard-side-to with the bow facing downstream.

As the tug swung, the eye of the AmSteel-Blue line turned on the recessed bollard. Stradiotti explained that when a line is put up to the deck of a ship, the crew passes it through a Panama chock to a bollard and so the eye doesn't swing on the bollard but bends on the fairlead. "So we learned that you have to put lashing on the line's eye to take the wear that would be caused by it turning and chafing on a recessed bollard."

Countless detailed practicalities like this, along with an encyclopedic knowledge of river and coastal marine history, have earned Stradiotti widespread respect on the river. Olson also has an extensive knowledge of the river currents and river tugs. He began work 50 years ago on another brand new tug called Sabre. It had a 240-hp Jimmy 6-110 and was used for towing up to 24 60-by-60-foot sections of logs in the river currents.


Shuswap's bow is fitted with massive fendering by Schuyler. (Alan Haig-Brown photo)

At 2153, the pilot, following a series of requests, was satisfied that the ship was parallel with the pier. He asked Olson to take back his line. Chinook had been moved to the stern quarter, so now the pilot directed Shuswap to the forward shoulder. As Olson swiveled the joysticks and tilts to control the rpm on the tug's two 1,600-hp engines, the 240-hp Sabre slid back into distant memory. The move to push on the bow allowed the ship's bow thruster to be turned off so that the little line boat could come in and take the ship's mooring lines.

At 2200 the pilot released Chinook with thanks and asked Shuswap to push easy on the ship while the lines were all secured. A half hour later, he asked Olson if he could pick him up from the pier and give him a ride across the river to his car. Coming aboard the tug, he commented on how easily the tug had swung the ship, but also noted that the ship had only a 26-foot draft, making it relatively easy to turn in the river.

The hull of Shuswap is designed to work well in the river currents. In the spring freshet, currents across the pier face can reach 5 knots. When pushing to the pier, a tug is typically working at 90° to that current. The z-drives make it much easier to hold position in these conditions, but hull shape is also important.

Modern harbor tugs often have a forward skeg to allow then to exert indirect mode stopping power on a ship. Shuswap has no forward skeg, and even the aft skeg, designed primarily for dry-docking, is not solid, so that the river current can flow unimpeded through it. While capable of providing general harbor docking, Shuswap is totally at home in the river.

Olson, Stradiotti, and other crews were given extensive opportunity for input on the design. Stradiotti pointed with pride to the system for launching the self-inflating life rafts.

"With this much beam," he explained, "this boat would be a long way over before capsizing. It doesn't make sense in a shallow river to have a life raft that will simply float off the top after it gets to the depth for the hydrostatic."

The docking tug is underway in the Fraser River near the Alex Fraser Bridge. (Alan Haig-Brown photo)

The life rafts on Shuswap are mounted one on each side of the cabin top, but they are on a platform on a long arm extending upward from the main deck. If the tug must be abandoned, the arm will tilt out, pass through a slot in the handrail and automatically launch the raft; an ingenious modification that officials wisely approved.

Such refinements can be found throughout the boat. Some, like the self-launching life rafts, arose from crew input and others, like the fendering, came from a combination of the naval architect and owners.

Most people who have spent any time around tugs have seen bashed and bent bulwarks in the stern. The bulwarks on Shuswap are set well in from the stern and canted forward at about 45°. They are not going to fall victim to the stern counter of a ship or to the rake of a barge.

In addition to this design refinement, the tug's hip and shoulder are massively fendered. Yahn explained that they installed additional fendering on the tug's pivot areas with a pair of huge tires from a wheeled container crane mounted forward in line with the dramatic sweep of the sheer line.

Bow and stern fendering is by Schuyler — 600 recycled truck tires were used in its manufacture. This approach keeps tires out of the landfill, while conserving oil and reducing CO2 emissions. The result was a savings of 7,920 gallons of oil and a 189,200-pound decrease in CO2 emissions.

After dropping the pilot on the opposite side of the river, Olson swung the boat back downriver for the short run to the home dock and office. Even at full rpm the wheelhouse is a quiet place where conversations are carried on in a normal tone. This is in part the result of the soft-mounted main engines and sound proofing in the engine room. In addition, the isolated pilothouse has been set on rubber shocks to keep any sound from being transmitted from the hull.

Asked just how quiet it is, Stradiotti took out his iPhone and brought up a special app. He held the phone up in the darkened wheelhouse and the green digits ran up and stopped at a remarkable 62 decibels. This is equal to the decibel reading of ordinary conversation, and for Olson and Stradiotti a far cry from the sounds on those old tugs with their Jimmys bolted solidly to their mounts.

The river and boat pride seen in the new Shuswap is acknowledged even in its name. The original Shuswap was built about 1917 by the father of Russ Cooper, the founder of the Fraser River’s first dedicated ship docking company.

The car carrier GMT Polaris began offloading its cargo of automobiles shortly after docking. By noon the following day, the operation was nearly finished, and by 1500 the pilot was aboard and ready to let go of the lines. Shuswap was back at the ship's side and pushing easy against her stern quarter. Taking the ship off the dock was a straightforward job as it already was facing downstream.

With the ship's moorings recovered, the pilot asked Olsen for half off the dock. Working alone, Shuswap pulled the stern out while the ship's bow thruster did the same for the bow. In minutes the ship was clear of the dock, and the pilot was marveling at the power of the new tug. With minimal effort, Shuswap had the ship free to move under its own power down river, with Tacoma, Wash., as the next port of call.

Satisfaction with the new boat is being expressed by owners, pilots and shipping agents. But many jobs require two tugs. Samson Tug Boats has the plans for a new tug similar in shape and design to Shuswap, but a little larger at 66 by 33 feet and with approximately 5,000 hp and about 60 tons of bollard pull.

The original steam-powered Shuswap spawned a series of successful tugs. It seems likely that the new Shuswap will do the same.

By Professional Mariner Staff