Following the success of the M15 Twin Sterndrive Interceptor launched last year at DSEI Defense and Security Equipment International show in London, Marell Boats of Sweden has now taken an additional step in the high-speed interceptor market.
Marell is launching the M15 Quad outboard open high-speed interceptor that includes fine tuning of the M15 hull, adding four Mercury 450HP Outboard engines on an extended platform, and support by dynamically operating jack plates. This vessel shows outstanding performance and manoeuvrability compared to other crafts in this highly competitive market segment.
High speed interception
The M15 is in particular designed for high-speed interception and boarding, with centre steering position for helmsman to optimise control and allow for full view of the surroundings during boarding manoeuvres and high speed turns. The crew and the officers are all safely and comfortable seated in Ullman shock absorbing seats which levels out the impact from the sea at high speeds up to 70 knots.
The crew and the officers are all safely and comfortable seated in Ullman shock absorbing seats
The raised fore deck creates a stable platform for the officers when approaching other vessels whilst the lower aft deck can be used when boarding smaller vessels and launching water crafts and rescue runners carried on deck.
The aft deck is a very flexible and stable multi-purpose platform from where users even can launch crew members to a helicopter and successfully carries out complex SAR operations in high seas.
Shipyard engineering team
The M15 has been extensively tested by the shipyard engineering team, with experience from high speed offshore racing, by the engine manufacturer following strict performance and durability test procedures, and also by the Swedish police in the Stockholm archipelago, with nearly 30.000 islands to navigate around.
All parties are very satisfied with the safe and stable platform and the performance results achieved with the strong moderate V-shaped bottom with hard chines, and longitudinal strakes, that shows no tendencies of chine tripping at full high-speed turns over 50 knots.
Other tests, like avoidance tests, U-turn tests and straight-line tests have all confirmed exceptionally high vessel performance, with results in excess of customer expectations. As one example, the vessel accelerates from 0 to 50 knots in less than 12 seconds without losing the sight-line to the horizon.
Meeting classification requirements
The vessel is designed to operate in very rough sea conditions, up to Sea State 6
The vessel is designed to operate in very rough sea conditions, up to Sea State 6. With the full body fore end, the vessel runs extremely dry with no green water on fore deck or spray on windscreens.
The hull plate of 8 mm and the special pattern of longitudinal and transversal framing allows the vessel to handle impact from the sea in speeds up to 70 knots without any damages or buckling tendencies of the hull.
Moreover, all Marell interceptors have a very competitive Total Cost of Ownership (TCO), as they are equipped with fuel-efficient solutions, designed to minimise maintenance and service costs combined with an engineering and quality approach to extend the life cycle. The vessel is built to meet classification requirements from Lloyds Register Grey boat code and with design assessment in accordance to Lloyds Register + 100A1 SSC Patrol HSC G2.
Tight building tolerances
The main vessel dimensions include the following:
- LOA (incl. engines and fender) 15.46 m.
- BOA (incl. fender) 4.18 m.
- Depth deck to keel at midship 1.50 m.
- Depth deck at foredeck 2.43 m.
- Draught max. (approximately) 1.00 m.
All Marell vessels are fabricated in jigs for the best quality and straightness. The jig frames forming the hull shape are precision cut with the same water jet cutting method as for the hull material. This precision work is thoroughly measured to be within the tight building tolerances.
Precision cutting machine
The deck girder structure of the Marell crafts are designed to carry sandwich composite deck panels
Also, cut outs for the lifting strakes are made in the jig frames with the precision cutting machine, making the jig a base for a very accurate hull production of the bottom and sides of the craft with possibility to build a number of hulls in same jig to identical dimensions and kept within very small tolerances.
The deck girder structure of the Marell crafts are designed to carry sandwich composite deck panels, which are glued to the girder structure. This forms a strong and watertight bonding and the deck panels themselves are acting as insulation against excess heat (from sun) and reduces the deformation of the hull in really hot deck temperature as the panels will absorb any elongation of the aluminium plating. By this method the M15 will be very suitable to work across all climate zones with great variations in air temperature and solar radiation.
Standard hull specification
The canopy is made of vacuum moulded GRP, to reduce weight and noise and isolate the crew area from the effects from both cold spells and burning sun. The novelty of this design approach makes the M15 craft suitable for both arctic and tropical conditions within the standard hull specification.
At present a third Marell M15 Closed Cabin Interceptor is being built and tested, for speeds above 50 knots and with a walk-around closed cabin. More information about this unique vessel with state-of-the-art stern drive propulsion systems and Humphree interceptors will come later this year.
