Greater efficiency, Smaller footprint
It’s counterintuitive that three engines can be lighter and more fuel efficient than two. It’s often true, however, and triple pod-drive installations are becoming increasingly common. The Amer 94 is the largest vessel in the world to be fitted with Volvo IPS.
Using the 94’s predecessor, the 92, as a yardstick, Amer’s engineers compared their new yacht’s triple-IPS, 2,700-horsepower installation with the 92’s twin MAN shaft-drive setup, which produces 3,600 horsepower. Less powerful and slightly heavier than the 92, Baccarat achieved 30.4 knots in their trial ( presumably less heavily laden than she was during ours) against the MAN yacht’s 32.4 knots. At their respective maximum speeds, the MANs consumed nearly 50 gallons per hour more than the Volvo Pentas.
Beyond the top line, the numbers get more interesting. The MAN V12 not only produces nearly twice as much torque as the six-cylinder Volvo (4,425 foot-pounds against 2,433), but delivers it right through the rev range, from 1200 rpm to 2100 rpm. The Volvo Penta’s torque peaks at 1300 rpm to 1500 rpm.
Torque is key to fuel economy. If you want to slow down to save fuel, you need torque to keep the yacht on plane. According to Amer’s trial, the fuel consumption curves for the two yachts cross at around 23.5 knots, when both the Volvos and the MANs are burning just less than 92 gallons per hour. Above that speed, the triple Volvo IPS installation is clearly the more fuel-efficient. Below that speed it’s MAN all the way.
There are advantages to a triple-IPS installation, but unless you spend the whole time at high speed, fuel economy isn’t necessarily one of them. — A.H.
LOA: 94ft. (28.65m) BEAM: 20ft. 8in. (6.3m) DRAFT: 6ft. 1in. (1.85m) CONSTRUCTION: fiberglass DISPLACEMENT: 64 tons (half load) ENGINES: 3 x 900-hp Volvo Penta IPS1200 SPEED (max./cruising): 30/26 knots FUEL: 1,849 gal. (7,000L) WATER: 475 gal. (1,800L) BASE PRICE: about $6,390,000 although the builder’s specs tout a top speed closer to 30 knots—she handles well. She provided a rewarding ride, even loaded down with nearly 6 tons of fuel and water, not to mention a 1,300-pound tender.
Much of the fun of driving Baccarat comes from the Volvo Penta electronics. Twin throttle levers are used in the usual way for the port and starboard engines, with the computer taking care of the center engine. Trim tabs are controlled from a single rocker switch on the lefthand lever, and we found that applying a reasonable angle of downward tab at all planing speeds added an extra knot or so, for free. The captain confirmed that the Amer 94 cruises comfortably and economically at speeds as low as 15 to 18 knots. At harbor speeds, the Volvo joystick controls the IPS drives. No thrusters are fitted, or needed.
Amer is a custom shipyard in Sanremo, Italy, that builds yachts pretty much any way the customer wants. Baccarat’s French owner wanted practical, conventional accommodations combined with a conservative, finely detailed interior by Stefano Tini. The fit-out is solid and well finished. She’s also quiet: A sound reading of just 62 decibels in the master suite at full speed is impressive. Big windows admit plenty of light, especially on the main deck, which is designed for relatively formal entertaining with a sliding door concealing the galley and wheelhouse. A cool glass balustrade encases the companionway on the starboard side without impeding sightlines in a notably spacious salon.
The tender choice is another unusual, but sensible solution aboard an unusual, yet sensible yacht. A triple IPS installation in a vessel of Baccarat’s size might be newsworthy, but the reality is not exotic at all. Like her captain calmly sorting out the anchor problem at a challenging moment in the channel, the result is resolutely practical.