Donzi R-80By Capt. Grant Rafter
If you plan on building an 80-foot sportfisherman that's capable of more than 40 mph, you'd better build her strong. Donzi Yachts believes it's done just that. Bob Roscioli founded the company 22 years ago, purchasing the rights to the Donzi name from the legendary Dick Genth. Although Donzi Yachts by Roscioli remains a separate company from Donzi Marine—its boats are all over 50 feet, while Donzi Marine's are considerably smaller—and its strength is its traditional way of building. According to Roscioli, the construction process for the R-80 is similar to the boats he originally built. Although some of the methods may seem like overkill nowadays, Roscioli's simple declaration can't be argued with: "It's tough," he says.
The boats are laid up on the west coast of Florida in Bradenton—next door to Sarasota where Donzi Marine is located, just to add to the confusion. From the beginning, Roscioli's boats are designed to take a beating. The hand-laid fiberglass hull is more than an inch thick. Four foam-cored stringers, which run the length of the vessel, are then lowered in and reinforced with uncut lengths of fiberglass and resin, a process the builder believes makes a stronger end product, since there are no seams or overlapping fabric. Transversals, bulkheads, and soles are then added, and tabbed in. Soles are cored with a foam that's more than two inches thick, providing acoustical insulation. More soundproofing comes courtesy of Soundown isolation mounts between the saloon sole and engine-room overhead. But unlike many boats, these soles are structural to increase the rigidity of the hull. Finally the superstructure is lowered into place and attached to the hull via a shoebox joint that's fixed with 3M 5200 adhesive, 'glassed on the inside, and then mechanically fastened. In other words, it's no meek boat.
And the components aren't wimpy, either. A pair of 2,400-hp MTU 16V 2000 M93 diesels allow the 80 to almost top 45 mph. Sea Torque shaft couplings are another oversize element, constructed of brass and lubricated with oil instead of sea water. Two of the four fuel tanks are outboard, but the Separ fuel-water separators are on centerline and aft of the engines for easy access. If any contaminant were to get through the filters, Airquip stripping hoses allow the operator to remove all the fuel from a tank, clean it in an inline centrifuge, and then send it to another tank, all while the engines continue to run. It's ship-scale technology shrunken for the 80.
There's other big-boy stuff onboard as well. Instead of a typical cockpit mezzanine, the 80 has a lanai—basically a sheltered porch. Its additional lounging space allows a veritable crowd to watch anyone fighting a fish without intruding on the 144-square-foot cockpit. An Eskimo ice maker, under the lanai's port tier, spews out a steady stream of slush for the prep table and cooler boxes. It seems almost intemperate, given the twin 18"x14"x20" freezers beneath the prep table (the same area to starboard is designated for tackle stowage), but the 80 is all about indulgences. An extra livewell is in the transom bulwark, beneath a teak caprail that has no gate above the tuna door; this prevents line snags.
If the captain wants to get closer to the fray, he can use a control station here just to starboard of the steps. It has MTU electronic controls with clearly marked detents, engine shut-offs, and steering control using both the Anschtz autopilot and the bow thruster. It's a setup similar to that in the tuna-tower helm except there the autopilot is supplanted with an Edson wheel and there's a VHF and 15-inch Furuno display.
On the bridge the main helm is, as you'd expect on this boat, also oversize and tricked out. There are three NavNet-3D-capable, 17-inch Furuno monitors, MTU engine readouts, oil-pressure indicators, a Palm Beach-style helm, and a panoply of other instruments. However, two features that I would have liked to have seen were missing: a rudder-position indicator and trim-tab indicators. The position of the rudders and the tabs can be intuited, but indicators are handy for quick reference. Donzi says they're aftermarket options (the rudder-position indicator should be on my test boat when she debuts at the Fort Lauderdale International Boat Show).
The weather was clear and the seas outside Port Everglades inlet were as calm as I've ever seen them, almost mirror-like. I eased back into one of three BlueWater helm chairs, all elevated on a five-inch-tall, teak-adorned step, and took the wheel. As the first of the MTUs' three turbos spooled up, she accelerated smoothly with a negligible increase in trim angle. At around 1500 rpm, the second turbos kicked in, and although the boost showed up on my acceleration data, I only noticed it because of a change in pitch in the sound of the engines. Around 30 seconds into her acsent toward WOT, the boat passed between 1750 and 2000 rpm and there was a slight vibration in the bridge sole, but the rest of the 60-second acceleration was steady and smooth.
Soon my test boat was screaming along at 45 mph, with decibel ratings not passing 84 dB-A (65 dB is the level of normal conversation), and I was having a blast. The boat was highly responsive at top speed, truly impressive for 70'6" of waterline. A large factor in her agility was the steering's four turns lock to lock (five turns at idle). Keeping the throttles pegged I banked the R-80 hard over, and she leaned gently into three to four boat-length circles without even getting the caprails damp. Easing back on the throttles, I took off all her headway to see how she maneuvered. She walked sideways easily, helped by her 38-hp Naiad bow thruster, so parallel parking her on a side dock should be simple enough.
Of course, getting an 80-footer into a tight slip would be a different story, and I wondered how this boat would handle the maneuver. With her throttles set one click forward and the other aft, she pulled slightly forward as she pirouetted, but that was simply compensated for with a little nudge astern. Sightlines from the flying bridge were fine: You could see the bow pulpit and both stern quarters while standing at the helm. Of course you can always climb up to the tuna tower, where every bit of rubrail is visible. But for most helmsmen, including our captain, John Huard, who had to maneuver her around the slip four times throughout the day as we shuffled people on and off the boat, the flying-bridge helm was just right.
As we took her upriver, making 7.5 mph with only one engine in gear, I climbed up to the bow pulpit and looked back, trying to get some perspective on this 80-footer. The glowing white expanse of her foredeck was reminiscent of any big sportfisherman, except that Capt. Huard looked much smaller—I could hardly identify him from this distance. And perhaps that was it. Everything onboard, from the build process to the cockpit to the engines to the controls, had been done on such a grand scale without sacrificing performance—and, in most cases, adding to it. She's a big, American-built boat meant to top the scales in speed and comfort. And with a 450-mile cruising range at top speed, this boat can get you anywhere you want to go. Fast.
For more information on Donzi Yachts, including contact information, click here.
Sea Torque is a small company from Stuart, Florida, that is making it big with its bolt-on shaft (B.O.S.) system. According to the company, the first benefit of installing its all-in-one shaft system is that it only takes about two hours for two technicians to fully assemble and install it. The next plus is the potential for as much as a five-percent reduction in fuel consumption and up to an eight-percent increase in horsepower due to the reduction of frictional losses in components such as the stuffing boxes, cutlass bearings, and water-lubricated seals. The entire system is enclosed in a non-rotating casing. Inside the unit there is, running from forward to aft, a transmission adapter, input shaft, double universal joint, thrust bearing assembly, output shaft and propeller bearing housing.—G.R.
This article originally appeared in the October 2008 issue of Power & Motoryacht magazine.