The Powerboat P1 World Championship last year presented many interesting and remarkable technical innovations that could provide new solutions for pleasure boats. Engine tests allowed the participating manufacturers - FPT Iveco (debut appearance), Isotta Fraschini, Lamborghini, Yanmar, Seatek, Mercruiser, Mercury Racing and Cummins - to test the strength and reliability of their products under critical conditions. However, some of the most interesting developments were to be found in the waterlines of some of the boats and above all in the transmission systems.

There were no real surprises or obvious innovations in the hull designs, however, some boatyards were clearly trying out alternative solutions to increase the performance of so-called 'step' hulls. Several experiments were used to test performance, modifying the inclination or longitudinal position of the steps on the hull surface as well as increasing and decreasing their depth. All of this harks back to the philosophy that Powerboat P1 is a useful arena for studying and developing alternative solutions using prototypes, without the need to invest large amounts of capital. The most important developments were to be found in the surface drives, whose different versions captured the attention and interest of many experts. Let's take a closer look - from the boatyards to the surface drive manufacturing companies - at how several Italian products were launched. We'll also examine the design philosophies behind these products and how the experience and brand image gained by taking part in the Powerboat P1 World Championships was used to increase visibility and aid marketing.
 
Experimenting new waterlines: Italian boatyards are consolidated in P1 and three new boats are launched

FB Design

Even though this boat already took part in the 2005 Championships, it is worth mentioning here because of the distinctive hull model, known as the STAB, which has also been widely tested for military use.  Only engineering genius Fabio Buzzi could have designed such a high performance hull that is so steady at high speeds: the three-step hull, tested in all kinds of competition, is very narrow. The real distinctiveness of the system, however, lies in the two small streamlined tubular networks fitted on the aft sides. Because they are positioned above the waterline, they don't create hydrodynamic resistance during navigation. When turning however, with the craft on its side, they become real 'buoyancy reserves' and act as stabilisers. The air reserve in the tubular networks pushes the veering boat upwards allowing for extremely tight curves at high speed and efficiently limiting the risk of capsizing.  The STAB is made from composite material, carbon fibre and Kevlar, and is equipped with technologically advanced accessories such as, for example, hydraulic shock-mitigating seats to cushion wave impact. When combined with ZF Trimax transmission this craft was almost unbeatable throughout the championships, coming up as one of the best performers in the P1 circus in terms of performance, reliability and safety.

 
Italcraft
 
Evolution and research were what drove Gianfranco Rizzardi, the driving force behind the Group that bears his name, to participate (as an entrepreneur this time, rather than a pilot) in the P1 Championship. Taking advantage of his acquisition of the Italcraft yard, a historic brand synonymous with high performance, his aim was to experiment and gain experience to use in standard production. This reasoning saw the new Sarima P1 (a wild card that only took part in one or two championship events), and the XT (based on the boat that won the 2005 World Championships with Andrea Bergamini, Maurizio Bulleri and Riccardo Fatarella), taking part in the Championships. These two boats were designed around their waterlines. The Sarima 38's mould was modified to include a slight step in the aft section of the hull, with smooth surfaces to increase water slide. The work carried out on the XT was more complex however. As we said at the beginning this design is based on the 2005 model that was modified several times in order to find the correct equilibrium and trim. After the winning results it was decided to use hull planes with several further slight modifications to the hydrodynamic support skids between the first and second steps on the hull surface. The boat will be mass-produced and sold as a high-speed pleasure boat. FPT Iveco were also involved in this interesting research and development project, via the collaboration of concessionary Emmecidue and RT Marine who provide the Top System surface drives.

Metamarine
 
Metamarine made its debut at the 2005 P1 World Championships. In 2006 the boatyard got its feet wet with two boats made from vacuum cured aramid fibre and epoxy resin. This assemblage of technology is now being used as a development model for a sporting pleasure boat. Mother company Metameccanica's mechanical part design and production capabilities led the yard to develop the boat's technical components as well: shock-mitigating seats, flaps, rudders, propellers and new 'Variante' surface drives.  With regards to the hull, the technicians at Metamarine chose to increase the quantity of channelled air, thereby increasing the aerodynamic pressure under the hull by creating a 'plate' that extends the hull plane below the step. The aim is to increase the amount of air drawn underneath the hull by creating a vacuum. This work on the hydrodynamic skid is not easy; because of the speed involved, the system should be able to increase the airflow under the step without modifying the depth of the step. The most interesting new development from Metamarine is however the 'Variante' transmission system. This allows the reduction ratio (i.e. the gears) to be replaced in just a few minutes before each competition according to marine forecast conditions. The system's protective casing is located on exterior part of the aft section and is made up of easily changeable gears.  In rough conditions you can therefore choose to fit a short ratio and vice versa in calm conditions a long one may be more suitable. This makes it possible to take full advantage of engine power and torque, changing not just the propeller's pitch, but also its rotational speed. The faster the propeller turns, the faster the boat goes.

Transmission systems: four systems in pursuit of ZF Trimax performance are tested at P1
 
The transition of technology from the sporting world to the mass market takes place with ever increasing rapidity, above all when it comes to propulsion systems. Boat designers and the market alike are constantly looking for power and efficiency. These two parameters are the essence of a racing boat. It is therefore only logical that the teams taking part in a world championship and the companies producing pleasure boat components can find the key to growth and success through collaboration with each other. The case of the Jolly Drive team that won the 2005 title thanks to the technical support of the transmission manufacturers the team was named after is an emblematic example of this kind of collaboration. The sporting results they achieved aroused the interest of German multinational ZF Marine, who have been selling the evolution of that product all over the world since 2006 under the name of Minirex. But what new insights did the last season bring, what new products are on offer from the companies that took part in Powerboat P1 2006 and which new products will soon be available from the pleasure boating yards? Here we'll take a look at four transmission systems that made their debut in competition this year.  At the same time, another great surface drive brand, ZF Trimax, has consolidated (if they ever needed to), the power, strength and reliability, as well as the efficiency of their systems, providing great performance in competition on the Kerakoll and Sunseeker XS boats.
 

ZF Trimax

Created by engineer Fabio Buzzi, this is the universally recognised surface drive. Designed several years ago, the Trimax was the progenitor in the development of this kind of propulsion system.
 

During the last twenty years of motorboating competitions, Trimax transmission systems have contributed to bringing the boats on which they were installed to victory, conquering 25 world titles and 51 speed records. Also widely tested on military vessels, they are very well suited to high-speed pleasure boats. Their distinctiveness is based on an extremely simple and efficient design that is therefore very light. Precisely thanks to their essentiality, they are extremely reliable and easy to install and maintain. High speed performance is not their only strong point, they are very efficient even at low engine speeds, allowing the boat to stay on plane at very low speeds (around 10-12 knots).

They therefore require little power from the engine. The propeller is 'ventilated' by air that comes out of an intake duct placed extremely close (only a few millimetres away) to the propeller blades.  The ZF Trimax is made entirely out of AISI 316 stainless steel and is formed of a shaft whose inclination can be adjusted (between 2 and 6 degrees) allowing the propeller to operate in the semi-surface and achieve the greatest efficiency (minimal slip) and performance. Propeller thrust is absorbed and 'dampened' by two special conical bearings which are in turn housed within an adjustable spherical bearing housing; the mechanical parts are lubricated by oil from a reservoir located in the engine housing. The fixed drive shaft provides elevated boat stability, whilst the rudder positioned behind the propeller provides precision when turning.

 
Flexitab
 
This company turned its attention to pleasure boating several years ago, joining Brunello Acampora's Victory Design, a company known for designing high-speed hulls. The team of experts that created the new Flexidrive transmission systems has a great deal of experience in high level offshore racing and counts on the scientific collaboration of the legendary Renato Sonny Levi, among others. Thanks to a research program developed with the Universities of Genoa and Naples, three different kinds of surface propulsion systems were developed under the common name of Flexidrive: Energy, Power and Speed. This last model was used in the P1 World Championships aboard the OSG Donzi craft at speeds of over 110 mph.

This propulsion system can be adapted to any kind of boat because it includes a mount that houses the hydraulic cylinder, which supports and trims the propeller shaft, and all the control elements (rudder and related hydraulic and mechanical circuits). The Powerboat P1 World Championships are surely the severest quality test for this product. There is no doubt that the levels of performance reached by racing boats are the sign of considerable propulsive efficiency and that the final results of the Championships are decided by high levels of reliability. But this is not enough. The OSG Donzi has an enviable trim in any sea condition and this brings to light the other important characteristic of this transmission system: it can adjust the boat's angle of travel along with its trim and give the boat direction thanks to the tunnels created near the propellers.

Top System

Top System is one of the new surface systems aimed at optimising the performance of super-cavitating propellers. The main innovative function of the joint system is that it allows the transmission to move to operate the trim and rudder. The joint system is made from steel and uses 4 hardened steel spheres to allow the joints to move, thus providing maximum mechanical reliability and a complete lack of vibration. One highly innovative feature is the total lack of torsion on the transmission casing; the shape of the joint acts as fastening point (as well as a joint fulcrum) for the transmission casing. All the thru-hull plates are completely watertight and fitted using steel double couplings (both on the bilge side and the exterior), for any kind of bilge operation even with the hull in the water. The swivel heads that connect the cylinders to the plates are made entirely from stainless steel and are completely corrosion resistant. The couplings are all made from flame retardant 316L steel and have double internal sealing rims to prevent water infiltration.

All components such as bearings, shafts and joints are made from specific use materials. The hydraulic cylinders, fitted with protective bellows on the rods, are also made from stainless steel whilst the protective bellows for the joint are designed to not create interference with the waterline. The sealing cover near the propeller is now made from a material that is inert to water currents in order to improve sealing. The rudder, with a 30degree travel angle, facilitates control of the boat both when manoeuvring and at the highest speeds. The hydraulic system allows the pilot to use the system with absolute simplicity thus providing maximum safety and precision. The size of the removable, directional fin can be adjusted according to use or boat behaviour.

Metamarine
 
This company, based in San Benedetto del Tronto, is continuing its expansion into boating via the launch of a new range of superb quality propulsion and steering systems, designed, patented and built by Metamarine.   The Variante surface drives have two exclusive characteristics: the traverse of the propeller shafts is correlated with the rudder angle and the built-in reduction unit is seawater-cooled. Let's take a look at the details. Being able to steer the transmission improves turning and craft control, increasing safety and precision also thanks to an electronic control system extensively tested in competition at over 100 mph. The built-in reduction unit, fitted on the transom, allows the reduction ratio to be adjusted very quickly. This means that the rotational speed of the propeller shaft can be adjusted according to engine rpm in order to find the most suitable 'gear' in any situation. It is this characteristic that gave rise to the name 'Variante'.   This product distinguishes itself for its exceptional strength and for the lack of pipes and systems outside the boat, which serves to protect the system from damage and fouling.   The trim angle is controlled by a hydraulic piston inside the hull extension structure; this is supported by a large mount that ensures the reliability of the assembly. The transmission shaft uses a ball joint, which allows it to move in all directions in complete operational safety ensuring maximum durability. The shafts can traverse by an angle of 12degrees to facilitate turning. An electronic control unit then regulates the steering angle of the transmission in relation to that of the rudder, following a precise programming logic, to make controlling the craft safe and easy even in the most difficult situations and at the highest speeds. In the event of a power failure or fault, the automatic system is excluded without causing any problems in control.

This system is used in competition to optimise propulsion according to sea conditions, whilst in pleasure craft it saves the boatyard time and money during the final tuning up stage. With this transmission the inverter gears can be changed in just a few minutes to gain the best possible performance. Another of this product's most important features is its extremely low power absorption and thereby increased efficiency for increasing the speed of the craft. During the design stage, Metamarine concentrated its efforts on reducing hydrodynamic resistance and mechanical friction. The new Variante system was successfully tested at the Powerboat P1 World Championships on two 43' TNT 46 craft, built by the same company and powered by 1700 hp engines: 'Fainplast' won three races and 'Kiton' came second place in the final results. The results of tests carried out at over 100 mph are the best quality guarantee for this innovative product, which is now available for all kinds of pleasure craft.

by Andrea Bergamini / Article courtesy of Powerboat P1