149
Sept 19, 2001

Quad Props and Booster Jet, For New Crewboat

Stuart Reeves of Mount Pleasant South Carolina operates boats as a business and an avocation. With five crewboats based in the Gulf of Mexico, he also has a 110-foot head boat based at Mount Pleasant near Charleston South Carolina. In addition, his boat company Star Fleet Marine Transportation, his associated company Oil Field Boats, Inc. provides brokering services to several other crew boats for which he arranges and manages leases. He knows boats.

When he decided to build a new 145 by 27-foot crew boat at Freeport Shipbuilding in Florida, he became interested in some earlier boats that incorporated a singe thruster jet set midships with four propellers set two to a side. Having recently repowered his headboat, Thunderstar, (see Cummins Hotips#97) with three of Cummins’ electronic controlled six-cylinder QSK19 engines rated at 760 HP each, he opted to go with the five of these IMO compliant engines for the new boat. But he was getting conflicting data on the advantage of the centre mounted engine which will have an 800 HP rating. No one questioned the draft advantage over a fifth prop on the centre line which would add 40 inches to the boat’s draft 6.8-foot mean loaded draft. This is a disadvantage when winter Northwesters rob ports like Morgan City, Venice and Intercoastal City of water and depth. The questions were around just how much speed he would gain with the addition of the booster jet and how that would stack up alongside the additional cost. Fleets already using similar propulsion systems, indicated four knots light speed and a proportional advantage loaded, but other sources argued that it could be as little as 1.5 knots gained.

On a boat costing in the $3 million range by the time it is in the water, the approximate $200,000 additional installed cost of the fifth propulsion unit has to be taken seriously. Reeves talked to industry people and consultants, but finally he went with his gut feelings as a boatman and an entrepreneur and told the shipyard to go ahead with the booster jet. The addition of the jet will influence the choice of prop sizes for the quad drives. With out the jet he would wheel the boat with four 40 by 38-inch propellers, with the jet he will increase the pitch to square the props at 40 by 40 inches. Reeves is estimating light boat speed of 24 knots without the jet and 27 knots with it. The boat will have rudders on the outboard propellers only.

Reeves is also having an electric tunnel thruster installed in the bow to ease wear and tear on the engines and stern when holding positioning under the rig. He estimates that the bow thruster, controlled by a joy stick, will reduce the amount of clutching and reving on the main engines by as much as 30 percent.

In anticipation of an increase in the number of rig companies using refrigerated grocery boxes, Reeves will have two Cummins powered 65 Kw gen sets installed with split busses. While a singe gen set will handle the regular boat needs, the second will provide redundancy in the short term and, with additional wiring, be capable of supporting the reefer boxes if required. The boat will have tankage for 22,800 gallons of rig water, 17,300 fuel, 1200 gallons of potable water and 1200 of grey water. It will be a zero discharge vessel for pollution rating.

Sea trials are scheduled for December of this year. Entrepreneur and boat man Stuart Reeves will be watching the GPS.

For further information contact:

Stuart Reeves
Starfleet Marine Transport Inc.
#4 Seafood Drive,
Mt. Pleasant, South Carolina, 29464
Phone: 843 884-4500 or 843 884-8889 Fax: 843 884-6803
E-mail: Stuart Reeves

Larry Neff
V/P Marine Marketing
Cummins Alabama Inc.
3422 Georgia Pacific Ave.
Moblie, AL 36617 U.S.A.
Phone: 334 452-6426 Fax: 334 473-6657

Jim Murray
President, Freeport Shipbuilding
116 Shipyard Rd. PO box 49
Freeport, Florida 32439
Phone: 850 835-4125 Fax: 850 835-4873
E-mail: Jim Murray

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