The high performance luxury superyacht Pershing 108 was launched at Fano on the Adriatic coast of Italy earlier this year with three V-16 engines in the 2000 range of MTU’s high speed diesel engines installed as prime movers rather than two larger units in the same manufacturer’s 4000 series that would have yielded about 500 bhp more. On the face of it a strange choice, worth examining for its logic; but first more about this fast (load displacement service speed 35 kts) innovative sports yacht.
Pershing 108: Photo courtesy of Ferretti Group
The Pershing 108
‘Pershing’ indicates a brand name with an honourable pedigree in the Ferretti group of yacht builders, and the model identifier ‘108’ refers to the length of the boat in feet (about 33 m). Interestingly, the propulsion system is an Arneson Surface Drive coupled to each engine to turn six-bladed surface-piercing Rolla propellors; a system which the manufacturers claim, amongst other benefits, reduces underwater drag by 50% in comparison with conventional submerged propellors. Prominent in the picture above, the plume-like spray of water thrown up in the wake at speed is characteristic.
Arneson Surface Drives & Rolla Propellors: Photo courtesy of Ferretti Group
The Pershing 108 is fitted out for extended cruising as befits its breed, under charter if required, since construction and fitting out was in accordance with the widely recognised MCA (UK Maritime & Coastguard Agency) code of safety. In addition to the impressive top speed an operating range of over a thousand miles at 11 knots is within the bounds of single, central engine, operation.
Accommodation includes four finely finished and appointed cabins for guests and three less imposing ones for the crew below decks, which, it turns out are less cramped for space than they might have been.
Benefits of Choosing the Smaller Engines
The designers chose three new version MTU 16V 2000 series M94 marine diesels engines (presented by Tognum at last month’s Cannes Boat Show) rated at 2,600 bhp (1,939 kW) at 2,450 rpm in preference to two larger 4000 series engines; firstly in the knowledge that the additional 9 tonne weight of the two larger engines would cancel out their roughly 500 bhp performance advantage. Thus the playing field was levelled for the following two decisive factors in favour of the smaller engines:
• Huge cost saving: reportedly two 4000 series engines would cost nearly €500,000 more than three of the smaller 2000 series
• Space saving: installing the smaller engines would allow more room for the crew accommodation
The large price difference per unit is believed to be due to the fact that the smaller 2000 series engine is widely employed in a variety of uses on land and sea on a large scale, allowing mass production of major elements of the engine, and consequent savings in the cost of production; a benefit not shared by its larger stablemate.
MTU 16V 2000 M94 Engine: Photo credit MTU