Formula 47 Yacht: Modern Diplomacy

Keeping the peace.

July 1, 2003

I was standing on the swim platform of the Formula 47 Yacht with the engines idling and chatting with the crew. What was remarkable was that we were speaking at normal levels. My decibel meter read a serene 66 dB-A. When we moved to the helm, the number dropped to 62 dB-A.

Formula made the boat so quiet by improving EcoSound, an underwater exhaust system designed to be installed on the transom. It routes exhaust fumes into the propwash to release them well abaft the boat, eliminating the station wagon effect (in which carbon monoxide gets sucked back into the boat). Formula licensed the EcoSound technology and integrated it into the 47 Yacht, molding inserts for the exhaust expansion chamber into the hull.

When the engines run at idle, the EcoSound system routes exhaust through bypasses that exit out the hullsides. Formula developed exhaust gas accelerators that are plumbed into the bypasses. The accelerators send the exhaust through a Venturi that has screens at each end and water injectors at eight angular ports. This helps to saturate the exhaust, which reportedly reduces decibel output.


Both the Sunseeker Portofino 46 ($650,000 with twin 430-bhp TAMD 74s) and the Sealine S48 ($692,225 powered as our test boat) use through-hull exhaust; the fumes exit the hullsides on the Sunseeker and go through the transom on the Sealine. This produces more exhaust noise at idle.

QUIET POWER. There are also performance benefits resulting from tweaking EcoSound. Because fumes are released abaft the propellers, the wheels don’t ventilate under hard acceleration or in tight turns. When I hit the gas, the 47 Yacht’s bowrise was minimal, and it reached cruising speed quickly. In turns, the boat feels more like a Formula go-fast, leaning into tight arcs.

To give the 47 Yacht a strong backbone, Formula developed a one-piece molded fiberglass stringer grid linked by small transverses. The boat’s partial and full bulkheads are formed individually from Diab closed-cell foam and glassed in place.


In the engine compartment, steel plates bonded into the tops of the stringers double as the anchors for the motors. A day hatch forward of the aft bench seat provides access for quick checks, but primary entrance to the engine compartment is gained off the swim platform. The hatch is hinged at the front, and you push a button near the aft cockpit bench seat to raise it. The genset is forward, as are all the fuel separators, including redundant units in case one gets too full of water or debris. The water heater is outboard of the starboard motor, and to port, the larger engine-starting batteries are forward of the shorepower cable retractor, which would make replacing them difficult.

SPACE CRAFT. With the engine hatch closed, there’s room for a waterbike or tender on the swim platform. Our test model had the hydraulic platform ($21,015), an item that comes standard on the Sealine and the Sunseeker.

The 47 Yacht’s trunk is set up with stainless-steel fender racks, dockline hooks, and extra space. In the cockpit the seating arrangement features a lounge that almost encircles the aft area, hinged backrests to port and starboard that lift up, and two more bottom cushions that fold out to fill in the circle. Along the portside, house batteries are in the seat bases. A locker to starboard is lined with a canvas pouch, perfect for a PFD. In a locker to port, I noticed exposed sharp ends of the screws used to secure the upper-lounge backrest. This area is intended for canvas stowage. Formula says it normally covers screws with plastic tubes, so check for yourself.


Glare is not an issue for the driver thanks to tan gel coat on the console ahead of the helm. Our test model has Volvo Penta’s engine-monitoring screens, meaning there are few analog gauges. Between the two seats at the 47 Yacht’s helm, there’s a 1’8″-deep stowage area beneath an armrest. On the backside of the helm seat, the wetbar has a sink, a wastebasket, U-line icemaker, and 12-volt cooler.

A walkthrough center windshield is rare on a 47-footer, but it sure makes it easy to get on deck. The nonslip and 2’6″-high bowrail enhance security, but I’d rather see the lower rail made of stainless-steel instead of a plastic-covered cable. In the 47 Yacht’s anchor locker, the windlass is beneath a locker hatch that opens on a gas strut, the chain drops into a dedicated box, and there’s a quick disconnect for a washdown.

DIVERSITY RULES. Make your way back through the windshield and you can head belowdecks, where you’ll find the highlight of the 47 Yacht, the midcabin or “den.” What sets apart this area is its versatility. The kids can hang out and play a video game on the flat-screen TV, or you could plug in your laptop. Unfold a cushion that’s secured against the aft bulkhead, and you can sleep two in separate berths. Push a button to slide the forward cushion up against the aft one to form a queen-size berth. And if one of your guests is taller than 6′, flip up the backrests along the starboard side of the boat to gain more legroom. The den has its own head with a small separate washing area and a dedicated air-conditioning zone.


The Sunseeker’s midcabin comes with two single berths and a private head. Sealine calls the S48’s midcabin the master stateroom. It has twin singles that convert to a double with a filler cushion and a desk with a plug-in for your laptop.

Moving forward, the 47 Yacht’s salon has an open feel thanks to ample headroom and the use of lighter colors on the wood and vinyl upholstery. To starboard, the galley, sink, and three-burner stove are recessed beneath a hinged section countertop. But the cabinet beneath the sink has carpet right behind the pipes, which will inevitably invite mildew.

The salon’s convertible cockpit/dinette table work flawlessly. The electronic motor is the same one used to raise and lower operating tables. Directly across the salon, the flat-screen TV tilts toward you for a perfect viewing angle.

The slip-off ends of the cockpit table stow in slots beneath the innerspring queen-size mattress in the forward master stateroom. It rises on gas struts. The head of the master berth is split in two and each half rises electronically.

And because the 47 Yacht runs so quietly, you’ll be able to watch your favorite show or read a book in peace, even when the boat’s running.

The Highs: As quiet as a Rolls-Royce and you don’t get diesel soot on the transom. A tight turning radius for this style of boat. Hidden rollers and dovetail joinery on maple cabinets a study in craftsmanship. An anchor locker that other builders would do well to emulate.

The Lows: It’ll take a lot of your money. Tough to get the engine batteries out. Lower section of the bowrail is made up of a cable. Carpet in the cabinet beneath the galley sink. Exposed screw ends in cockpit canvas locker.

EXTRA POINT: If you’re hooked up to city water while at the docks, a bypass in the plumbing lets you fill the boat’s water tank, and when it’s topped off, an automatic shutoff closes the valve to return the system to normal operation.

LOA………………….50′ ** **

Beam………………..14′ ** **

Draft (max.)……..3’8″ ****

Displacement (lbs., approx.)……….31,500 ****

Transom deadrise…………..18° ****

Bridge clearance………….14′ ****

Minimum cockpit depth………………2’7″

Max. cabin headroom………..7’6″ ****

Fuel capacity (gal.)…..350 ****

Water capacity (gal.)…..100 ****

Price(w/standard power)…….$777,660 ****

Price (w/test power)…….$777,660

Standard power Twin 480-bhp Volvo Penta TAMD 75P EDC or 480-bhp Cummins 480C-E in-line-6 diesel inboards.

Optional power Twin diesel inboards to 1,320 bhp total.

Test boat power Twin 480-bhp Volvo Penta TAMD 75P EDC in-line-6 diesel inboards with 444 cid, 4.21″ bore x 5.31″ stroke, swinging 26″ x 30″ four-bladed Nibral props through 2.1:1 reductions.

Standard equipment (major items): Electronic windlass w/200′ of chain; windshield wipers/washers; radar arch; transom shower; 240v shorepower w/50a cord, Glendinning retractor; city water connection w/Glendinning retractor; Bennett trim tabs w/switches and indicators; Raymarine 520 chartplotter; VHF radio w/antenna; hydraulic steering w/Dino tilt wheel; auxiliary 12v outlet; in-dash AM/FM/CD stereo w/6-disc changer, 4 speakers; cockpit wetbar w/sink and refrigerator/icemaker; Bimini top and aft canopy w/front and side Strataglass enclosure, aft and side curtains; Panasonic 22″ flat-screen TV; Kenwood surround-sound stereo w/5-disc CD/DVD player; Bose home theater system; CO detector; 16,000-Btu reverse-cycle a/c; central vac.; U-shaped galley w/sink, 3-burner stove, microwave oven, refrigerator/freezer, coffeemaker; galley fire extinguisher; water heater; 2 heads w/Vacu-Flush commodes; circular shower stall w/rainwater head; power engine hatch; 12v oil exchange system; engine start and house batteries; 160a battery charger; 2 auto. bilge pumps; high-water alarm; 12.6kW diesel generator.


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