Superyacht.eu Nautica Digitale
Share this page
Tell a friend


SUPERYACHT #9
Summer 2006

Article selected from our quarterly magazine dedicated to the largest and most luxurious boats with information, interviews, technical articles, images and yachting news


Summary

Subscription

Yachting catalogue

Navigation tests

Used boats

Boatshow

Video Nautica

Article by
Alfredo Gennaro


SUPERYACHTS AND ENGINES
A COMPLEX COUPLE

PART TWO

In the first part of the analysis we began to analyse selection criteria and discussed "trials" and "numerical presence". In this second and last part, before drawing the final conclusions, we shall examine another three aspects which might condition choice.

The Manufacturer

Financial solidity is a symptom of good quality: or at least it used to be when customers didn't even know the shareholders or owners of the company they bought the product from. And maybe it wasn't such a bad habit, since shareholders tend to seek profit while managers have to employ the good business sense that will ensure its achievement.

Whereas management today exploits financial alchemies that have nothing to do with fineness of the product, experience and skill of the workforce or evaluations of the customer. The latter, who was once considered a company's main asset, is now erroneously considered as a marginal advantage drawn along by company strategies or by missions defined by boards of directors who read statistics or consultants' reports.

So though it may be true that the bigger the group the greater the guarantees offered by the product, we would not advise a choice based on this parameter, preferring concerns that are smaller and therefore more reactive to market variations and more attentive to the asset represented by their clientele.

With dismay we followed the disappearance of OMC, considered the most important outboard manufacturing group, and breathed a sigh of relief when its operational companies returned from the world of finance to become the production company Bombardier.

In January came the news that MTU had been sold to a Swedish financial company by the Daimler Chrysler Group. The official reason for the sale sounds pretty dumb: Daimler Chrysler wants to concentrate on the mission it believes to be strategic, the vehicle sector, and needs to get rid of marginal activities. We should like to understand something more, and we continue to wonder.

The reason could be one of two:

The whole group is in difficulty and has sold the family jewels to regain liquidity, like soccer teams that train players and support themselves by selling off when the players have achieved a certain market value;

MTU is in difficulty and the group decided, erroneously in our opinion, not to rescue it but to get rid of it while there was still time.

Two considerations must be made: transfer of a marginal company to a financial group is not a good sign. If you remember the plot of "Pretty Woman", and for a moment set aside Julia Roberts' beauties and "services", you'll recall that the male lead's job was the financial dissection of companies, and that it was precisely a shipyard that gave him back his taste for building up, for doing something positive.

It's precisely the pleasure craft sector that gets fond of engine suppliers, and it can't bear betrayal: we think that whatever the reasons for the MTU sale, whatever the marginality of yachting related companies, it should be kept in mind that their customers are very attached to them, so there is an asset that ought to be added to purely financial estimates and evaluations. To back up a marginal company or activity when it isn't doing so well is certainly no pleasure: but it is extremely reductive, with regard to company management's sensitivity and abilities, not to recognise relationships and fidelity as asset and human related aspects.

Production Technology

We've often been invited to visit production premises or research laboratories and we've always reported to Nautica readers not only what we saw but also the sensations we felt and how much these sensations might be linked to passing judgement on a product. Our experience as technicians and our culture of quality mean that we recognise when things have been organised for the occasion and when, contrarily, we have been invited to bear witness to a routine which, with or without our presence, would have been carried on in exactly the same way on the same day.

Of course the fact that everything is organised, clean and perfect cannot take anything away from the technical content of what we are shown, but in our opinion it's far more important to see normal life on the premises or in the laboratories we're invited to visit. We could say that there's a fundamental difference between "being invited for a visit" and "being admitted for a visit". We far prefer the latter: maybe there won't be a guide to explain things in accordance with a programme, but there will be the spontaneity and pride of individual responses - stimulated by an outsider's curiosity - on the work they do and the results they achieve. Rather than the printed matter set out on the meeting room table, with production or test reports, we prefer a photocopy of something we have come across there and then by chance. Rather than video illustrations or computer presentations followed by guided tours, we prefer an informal stroll through the premises, accompanied by someone who can elicit direct responses from the people involved.

We've had these informal experiences on several Volvo Penta premises in Sweden where, as we said, we are invited almost every year.

We had an even pleasanter and more indicative experience at the Charleston premises of Cummins Marine where we were left free not only to circulate but also to ask for and receive confidential documents dealing with defects or with engine trial rooms.

Yes, because apart from the modernity and perfection of the production apparatus, it is in the trial rooms that engines are put to the test, and free access to engine room trial reports gives a competent observer the chance to judge how work is carried out, and this puts the company on a level of confidence and routine which does not fear negative judgements.

In second place, regarding possibilities of judgement, we have programmed visits, more suited to non-technicians and demonstrating more organisational than technical abilities. Under this heading comes the visit to the IVECO research laboratory where we cast an eye to the future; or the Caterpillar premises at Charleroi in Belgium to inaugurate a European scanning of measurements and components.

Before concluding this aspect of things it should be pointed out that while the visits to Cummins and Volvo Penta concerned premises that manufacture marine engines, the other visits, which were interesting and instructive, had to do with diesels in general. On the one hand this is more significant because it involves overall aspects, while on the other hand we must confess that when one speaks about marine engines one finds less formal behaviour, which is associated with awareness of marginality but also of the importance of the personal relationship, which becomes confidential and direct and therefore more complete and explicit.

Engine Technology

And here we come at last to engine technology. The identikit of a big marine engine is easily drawn: they are usually four stroke diesels which may have two or four valves per cylinder and indirect cooling with exchangers or plates. The turbocompressed version flanks or replaces the aspirated one. Cooling systems can involve either gases compressed before supply to the cylinders (intercooling) or exhaust gases that supply the turbine (aftercooling). The classic configuration is the modular one of six inline cylinders with cranks at 120°, in one, two or three banks of a differently angled V. As is well known, and as we have explained exhaustively on various occasions, the six cylinder configuration is the best balanced from a dynamic viewpoint with view to the inertias of alternative masses and their moments with regard to both the engine axis (first order moments) and to the engine transversal symmetry plane (second order moments) such as to theoretically render functioning possible without a flywheel.

But the important newcomer in recent years is electronic management which is increasingly gaining ground even in the most traditional circles: the computer comes aboard with the engine and controls its main functions through injection piloted in such a way as to be the most suitable for quantity and timing. The only manufacturer to continue with traditional mechanical injection is Deutz: all the others, some more extensively and in a more integrated manner than others, have studied management logics that improve performance and save fuel but above all make it possible and easy to remain within the increasingly strict limits to safeguard the environment from exhaust fumes and noise. In the November 2005 number of Nautica we explained the meaning and advantages of common rail, pointing out that it can function only because the electronic control unit handles delivery and imposes functioning maps adapted to the conditions picked up in real time by the sensors.

Is all this a good or a bad thing?

For a long time we have been against on-board electronics, convinced that it would mark the passage from a "manual" to an "instrumental" epoch. With handling of phenomena and adjustment passing from our senses, with non- specific instruments, to the knowledge of complex logics outside our generalised culture and current practice, with specific equipment. Which in fact is what has happened.

Engine timing, an operation that even a mediocre mechanic can carry out with the appropriate manual, becomes complicated when you have to set it in a complex mapping that envisages variability in function of signals that come in real time from sensors.

On the other hand, the widespread use of portable computers and internet connections makes both management and adjustment possible - even breakdown repair - through online contact with the manufacturer's specialised technicians, so a capillary service network is superfluous apart from good availability of spares.

There is therefore a substantial difference between the professional use of engines for work such as fishing or transport and the use of engines on pleasure craft. The former, by tradition and culture, prefer the manual aspect of intervention while the latter expect and also hope that everything can be carried out without anything being done by skipper or crew: if there is a computer on board, as well as radar, SATNAV and control integration, why should there not be engine management, not only with regard to its functioning but also its integration in the complex grouping of required performances (suspension of torque when the inverter is activated, reduction to the minimum of active cylinders etc.).

The two possibilities described apply to two schools of pleasure craft sailing:

on the one hand those who want to be relieved of anything that might impede their full enjoyment of time spent at sea;

on the other hand those who think that taking away the skipper's responsibilities and challenges, the merits and difficulties of running the ship, will also take away his love of going to sea

As things stand, both schools will be able to find the engine that meets their needs.

Conclusions

It would appear that what we have said does not and could not give precise indications to a skipper who wants to buy a superyacht: and in fact our aim was not to give recipes but to stimulate reflection before arriving at decisions or assumptions which, for better or worse, may have an antithesis which, arising from enthusiasm or advice that is rarely disinterested - especially if not asked for - should generally not be given much weight.

A pair of superyacht engines is no small matter: the decision calls for careful evaluation of the pros and cons, a series of meetings with manufacturers, a raising of your guard, a professional type choice. You must replace the engine brochures by dialogue with the designers and users, if they are available. Data regarding power, torque and consumption must be replaced by or added to more complex formulations such as rating, continuative power, the average time the maker guarantees between one breakdown and another, whether the repair can be carried out on board or if the engine has to be unshipped: these are called MTBF (mean time between failures) and MTBO (mean time between overhauls), and the latter must be much greater than the former and must satisfy the user's requirements in function of the use he intends to make of his yacht, keeping in mind that unshipping engines is not a simple matter but may on the contrary be envisaged as routine in reconditioning.

The skipper should furthermore draw up a scheme of how he intends to use his yacht, envisaging range and time of use: these forecasts may orient choice towards manufacturers that are strongest and best established in the relevant area. Because though it is true that on the one hand most engines are of high quality as long as all goes well, it is when something goes wrong - which can always happen - that you see the manufacturer's reaction and his ability to handle the problem: it is always preferable that he be nearby.

Don't neglect looking at the duration or response tests that your chosen engine has passed at sea (there are murderous tests which an engine is unlikely to pass with flying colours if it has design or duration defects): ask for cycles and results and study them carefully, keeping in mind that there is a classification of companies, which is important but not enough to guarantee product quality. Two healthy and robust parents generally produce a healthy child, but the child might also turn out to be weak and sickly: certification has to concern the child and not merely the parents who have given birth to it.

Lastly, but with great caution, trust the shipyard's choices. Usually they have no personal interests in suggesting something they don't believe in, especially if it is a serious shipyard that above all is fully responsible for everything installed on the vessel you have bought.

Full steam ahead!