Denis has never designed an ordinary boat in his life. And MV Focus is no exception. These pictures were taken on the day she was launched in March 2007 - so certain necessities like safety rails etc are missing....but you get the general drift! Denis describes MV Focus as a "yachty's powerboat". By that he means she has a low profile (safety and low windage), and an easily driven displacement hull (economy).
MV Focus also has a 130 hp John Deere diesel and carries 7,000 litres of fuel. As she uses under 1 litre per nautical mile, Denis reckons after an initial fill-up, he'd only need to re-fuel 3 times to go around the world.
Among other innovative features on MV Focus is the way water ballast can be used to replace up to 3 tonnes of the weight of fuel used.
Inside, MV Focus is a blend of modern and traditional - hugely spacious as the accommodation is built using the full width of the beam, like most yachts. Another innovation is the accessible "utility room" in the space aft of the main saloon, which houses the generator-cum-wing-engine, laundry and air conditioning unit.
22 October 2007. But I've just received Denis' description of MV Focus (below) so I'll let him tell you more about it:
FOCUS
Length – Overall 56 feet
Length – Waterline 51.14 feet
Beam - Overall 14.5 feet
Draft 5 feet
Maximum displacement 28.64 tonnes to designed waterline
Immersion rate 3000 lbs (1364 kg) per inch
Maximum hull speed (speed/Length ratio 1.34) 9.58 knots
Economy cruising speed (S L 1.0) 7.15 knots = 171 miles/day
Hull construction is three skin diagonal cold molded over a male mold and heavily glassed both sides to become an epoxy/GRP/timber composite. There are no stringers, all interior components being glassed to the hull to form the divided structure. The 28 inch propeller is protected in an aperture behind a full length keel/deadwood. Substantial rub rails protect the topsides, and raised bulwarks provide security on the foredeck.
The owners cabin is forward with an island double berth and ensuite bathroom. Aft of this is the double guest cabin with the main bathroom opposite. This bathroom incorporates a combined shower/bathtub.
Routine access to the engine room – situated under the wheelhouse – is via this bathroom, so that entry into the engine room when on passage does not release engine heat, noise or smell into the accomodation. The engine room is kept basic and spacious with the main engine and fuel management system being pretty much the only occupants. The battery banks are housed outside of the engine room in blower ventilated compartments. The effect is one of conspicuous simplicity and ease of access for service and maintenance. Other services that could have been in the engine room are combined into a separate services room aft This services room houses the auxiliary engine with refrigeration compressor, hot water service, the steering gear, air conditioner, inverter, and backup 240 volt freezer. A benefit of this aft position for the auxiliary is that in the event of fire or flooding in the main engine room (where auxiliaries are commonly situated) use of the auxiliary is not also lost.
Above the main engine room is the wheelhouse incorporating all the normal steering and navigational functions. Though electronic charting is mostly used there is also a chart table large enough for a fully spread paper chart. A comfortable helm seat with good visibility is provided, and two settees which double as sea berths are close to the pitch centre of the vessel. The wheelhouse is the most in use area at sea. Aft of the wheelhouse, stairs lead up to the flybridge which incorporates steering, autopilot and engine controls, and bowthruster and anchor winch controls. Good all round visibility is enjoyed from here – both for at sea and for berthing the vessel. An outdoor dining/lounging area is aft of the flybridge steering position. Good visibility is maintained down into the wheelhouse to monitor all switch panels, alarms, engine instruments, autopilot, GPS, radios and the electronic charting screen, so no repeaters are needed.
Aft of the wheelhouse the full width saloon/galley is 4.4 metres x 4.4 metres which gives a feeling of considerable spaciousness. Aft again is the services room, aft covered cockpit and the boarding platform.
Much of the sub sole area forward and aft of the engine room is occupied by the fuel tanks, water ballast tanks, and fresh water tanks, all of which contribute to a low centre of gravity and offer the opportunity to vary the fore and aft trim.
FOCUS has recently completed 2000 miles of coastal sea trials in preparation for heading off on planned blue water cruises.
FUEL COSTS AND THE OCEAN CRUISING POWER BOAT
A primary design objective for FOCUS was to create an ocean capable power boat of simple, inexpensive construction suitable for the home builder, with accommodation primarily aimed at full time liveaboard cruising for a couple, though a family of four or 2 couples are provided for, and up to 8 people for short periods is no problem.With lengthy passages envisaged, fuel economy was of great importance and a target of one mile per litre was set. It was calculated that this could be achieved at 6.5 knots, and in fact that level of economy has been exceeded – with one litre per mile being maintained at the speed length ratio of 1.0 ( 7.15 knots) or a little more – up to 7.5 knots depending on load at the time.
Fuel economy is not just an issue of consumption, but also purchase economy, and is maximised by buying as much as possible at the best price. Factors influencing this include large fuel capacity, which is often sufficient enticement for getting a bulk tanker to deliver fuel, usually at a considerably better price than the dockside refuelling facility. Also, when departing for overseas, fuel in some countries is purchased excise free, which is a worthwhile saving if getting a good amount of it. And last, but not least, there are still some countries where diesel can be bought very cheaply, and on a lengthy, international cruise this could be a huge saving if the vessel can make it from one favourable refueling country to another, rather than having to refuel at the conclusion of each long passage.
This became a prime factor in the design of FOCUS. Clearly a large fuel capacity was essential, hence a hull that could carry a large fuel weight. This eliminated a power cat from consideration despite other attractive features, and in the final design 7000 litres of diesel tankage was allowed for. This fuel weighs 6 tonne so empty fuel to full fuel is 4.4 inches (110mm) immersion, which is well within the load limits for this design.
To put some perspective on the fuel capacity issue FOCUS could circumnavigate the globe on an initial full fuel load and just 3 refuels. Much of the refuelling could bespaced to include countries that do have very cheap diesel prices. A Pacific cruise could be completed with no refueling en route.
The fuel economy on FOCUS is delivered through a John Deere 6068, a 130 horsepower naturally aspirated 6 cyclinder diesel. Full power is at 2400 rpm but the targeted cruise speed is delivered at 1500 to 1550 rpm, which the power curve for the engine suggests is utilising about 32 horsepower and requires 7.1 litres per hour, which equates pretty well with the measured performance. This was the big surprise when we initially investigated the economy of low speed, easily driven displacement hulls – just how economical it is if we are willing to travel slowly. The targeted speed range is at the upper end of what most cruising yachts are achieving anyway, so, with a sailing boat background, we have not found it difficult to get used to. The consistency with which it can be achieved over a large range of normal weather conditions makes planning a passage very predictable.
Confirming the easily driven hull shape is the performance with the 27 hp Yanmar 3 GM auxiliary engine. We hadn’t been expecting too much with this back up unit which is primarily used for refrigeration and hot water services, and for charging batteries when not under way. But for back up propulsion it is provided with a V drive transmission and a two blade folding propeller. In flat water this engine drives the vessel as follows–
4 knots at 2000 rpm 5 knots at 2900 rpm 5.6 knots at 3600 rpm (27 horsepower)
Our conclusion is that powerboat voyaging is decidedly more affordable than many people realise as long as very moderate cruising speeds are targeted, and in the case of a vessel the size of FOCUS we could cruise for many years under power and still have outlayed less money than a sailing rig would have cost initially, even without factoring in all the ongoing sail and rig costs. The ongoing costs of powerboat cruising other than the fuel should, by comparison, be much lower, given that a heavy duty diesel engine such as the John Deere 6068 can be expected to give up to 25,000 hours trouble free (175,000 miles) before needing major maintenance if properly and regularly serviced. Such ongoing costs as might be experienced are likely to only be similar to those that a yacht auxiliary might require anyway.
Email Denis on denmofocus@dodo.com.au As of January 2011 MV Focus is for sale. Click here to see more about this boat.
