Mobile Marine Introduces Advanced-Design Workboat
Mobile Marine Ltd. of Corradino Heights, Malta, recently unveiled a new design of general- purpose workboat suitable for a wide range of duties.
Known as the Mobile-165 (the designation being derived from the craft's 16.5-meter overall length (about 54 feet), the boat is constructed of glass-reinforced plastic (GRP) and features air lubrication of the hull underbody to provide improved performance characteristics. In its prototype form, the Mobile-165 has a cabin aft and a bow ramp, but Mobile Marine has designs for a number of variations and can build vessels to specific requirements based on the standard hull and machinery layout.
Among the duties that the builder sees the basic vessel being able to perform are those of vehicle or passenger ferry, freight launch, harbor tug, anchor-handling vessel, survey launch, oil pollution control vessel, or diving boat.
The hull of the Mobile-165 is constructed of GRP using E glass chopped strand mat and woven roving with Lloyd's Register-approved boatbuilding polyester resin. The beam is 4.7 meters (15.4 feet), providing a deck width of 3.8 meters (12.5 feet). Loaded draft is 0.5 meters forward and 1.5 meters aft (1.64/4.92 feet). A sealed, foam-filled compartment below the vehicle deck provides 35 tons of positive buoyancy.
Mobile Marine recommends the use of twin six-cylinder, turbocharged marine diesels, each having a continuous rating of 200 bhp, and has installed Perkins TV8 540M units in the prototype. These will be offered as standard, but the design will accommodate other manufacturers' engines without difficulty. These engines, which drive separate propellers, provide a service speed of 14 knots but the hull design is suitable for greater speeds and higher-powered installations are possible; 20- 21 knots with a payload of 20-25 tons is quite feasible, according to Mobile Marine.
In its prototype form with cabin aft, the Mobile- 165 provides accommodations for 24 passengers. Forward of the cabin is the working deck with an area of 49.4 square meters (531.5 square feet) able to handle up to six cars, depending on size. The deck is served .by a bow ramp 3.3 meters (10.8 feet) wide, which can be lowered at sea to facilitate diving or salvage operations. By modifying the cabin arrangement, two 20-foot containers could be carried.
A novel feature is the air lubrication of the hull that makes it easier to drive, Mobile Marine claims, thus providing greater speed or fuel economy, depending on priorities. Four skegs extending the full length of the hull create three equal-size tunnels in which air is trapped and thus forced under the hull as the craft is driven forward. The outermost skegs prevent escape to the sides, and most of the air exits at the stern. The entrapped air also provides a cushioning effect in choppy seas, giving greater comfort for passengers and crew. The design is capable of operating in relatively rough conditions, up to Force 4 or 5.