The Importance Of Choice: A Motorsailer Offers The Best Of Both Worlds

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There’s a major difference in passagemaking between motor and sail: it’s all about options. Namely, when you can go or when you would be better off waiting for a calmer patch of weather and waves before venturing out of a nice, comfortable anchorage to travel to another.

I have no prejudice against motoryachts. They’re very comfortable and can be configured inside as much as a land-based home can be, and given appropriate weather, they can be taken offshore between ports or other anchorages as fast as an owner’s wallet and the boat’s fuel tanks and rate of consumption will allow. In doing so, they will generally sit flat in the water with minimal rolling (given adequate bilge keels or gyro-driven stabilizers), so the amount of packing up and strapping down of decorations and personal kit is quite limited.
A motorsailer like the Mandarin 52, which is the focus of this story, has the advantage of being capable of tackling a far wider range of weather and sea conditions without damage or even discomfort, and so it offers more options for moving from one place to another. The disadvantage, of course, is heeling angle. Please note: that’s heeling angle, not roll. Sailing boats don’t roll a lot; they reach an angle of heel and stay there. How much heel depends on how much wind and how much sail, and the latter depends on how hard the owner wants to push the boat to get somewhere.
There’s some packing up necessary, of course, and it is more than what’s involved in getting a motoryacht ready for sea—but not much, and possibly no greater amount, as long as the boat has been configured properly in the first place. Huge double beds, as seen in a good many motoryachts, become unusable in a fairly small seaway anyway, unless they’ve been fitted with the lee cloths or leeboards commonly found on sailboats. Galley kit such as stoves need to be gimbaled for use in a seaway, and refrigerators and freezers need fiddles on shelves or access from the top to prevent everything from falling out when the door is opened.
TIME TO GO FARTHER

These are very minor compromises compared to the advantage of so much more time becoming available for the passagemaking itself, and hence for the opportunities of traveling farther and seeing more and farther-flung places.
It’s for these reasons that the Mandarin 52 stands out. Yes, it’s a sailboat, but it’s a motorsailer, meaning that it can keep up a reasonable speed even when the wind is light or has vanished altogether. Given a reasonable breeze, it’s nimble when under sail alone. It’s also very comfortable.
To prove the point about distance and time options, let me describe a passage made by the Mandarin 52, Witchway, which in 2007 was motor-sailed from Ensenada in Mexico’s Baja California (about 90 minutes’ drive south of San Diego) to MacKay in Australia, just south of Queensland’s Airlie Beach—a total of almost 7,000 nautical miles covered in five stages, taking the best part of 43 days at sea.
First, some details about the boat: Witchway was built in 1999 in Zhuhai, China, by Seahorse Marine for airline pilot Chris Hancock. Chris, being both a pilot and a fair dinkum Australian, looked after the boat meticulously until selling it in 2007. He added items such as solar panels and a wind-powered generator, an extra air conditioner, a dehumidifier, a watermaker, a fuel-polishing system, and a scuba-related air-compressor, plus a barbecue, a HF radio, and a weather fax. The total—the list of add-ons is far longer than the sample I’ve mentioned— was about 10 percent added to the basic boat’s cost of U.S.$499,000.
The hull has a waterline length of 46 feet 2 inches, giving a hull speed of a fraction over 9 knots. The boat is fiberglass, with extra layers and extra resin in appropriate areas for sealing and for load-bearing. The bottom has four fore-and-aft stringers instead of the usual two, permitting a honeycomb-lined structure for superior strength. The engine is a Cummins 220hp six-cylinder turbocharged diesel with soft mounts to separate it from the hull and to cut vibration. The feathering prop (one of the extras) has four blades. Fuel tanks are fiberglass with thick sides and baffles; two side tanks each hold 250 gallons (about 945 liters), and there’s a 100-gallon (375 liters) operations tank in the keel, for a total of 600 gallons, or about 2,200 liters.
CONSTANT COMFORT

Electronics are well thought out, with lots of indirect lighting to cut down the “workshop” effect found in many cruising boats, and the wiring runs are contained in conduits that are easily accessible and are above the waterline, except for wiring to bilge pumps. The system is designed to have the refrigerator, freezer, galley, lights, and entertainment center available all the time, sailing or moored—the builder says this is the difference between living aboard and just riding aboard.
The cabin layout has a couple of options for forward accommodation: a V-berth cabin forward plus a double bunk side cabin to starboard, or a large forward stateroom with a regular double bed. Either way, there’s also a massive aft cabin with a double bed. There are two electric heads. The saloon has 7 feet of headroom over most of its full-beam, a 15-by-10-foot fore-and-aft area with an open layout that emphasizes its spaciousness. The dinette to port can easily seat six, with its seat able to be used as a single berth, while the saloon settee can become another double berth.
The galley is 10 feet long and has a twin sink, a gimbaled electric stove with an oven, and a large fridge and freezer all as standard. There’s space for a dishwasher or an optional trash compactor. There’s loads of storage space throughout the boat, with a walk-in storage locker forward, bins under the saloon, and spaces under the furniture.
BELT AND SUSPENDERS

Unusual for a cruising sailboat these days, the Mandarin 52 has a pilothouse, with a raised U-shaped dinette on the port side that can become a boxed-in sea berth. To starboard is the helm, with seating for two. Instrumentation is a matter of choice and wallet, though the basic fit has a navigation compass and many electronic alarms for all systems, as well as a VHF radio, autopilots, radar, GPS, chart plotter, and so on.
The pilothouse is a guardian in disguise. Yes, it has a large chart table and storage for charts, plus a space for a fridge or ice maker, and it can serve as a great area for socializing. But it is also fully scuppered in case a powerful sea breaks through the big windows—the forward panels are sloping and are 0.4 of an inch (10 millimeters) safety glass anyway—and the side windows have wooden storm boards available. The companionway to the saloon also has a hatch and storm board just as if there was no pilothouse roof, so the effect is a “belt-and-suspenders” approach to keep the water out.
The rig is 62 feet high off the waterline, 56 feet measured from the deck. Sail area is 1,200 square feet, counting only the main and a working (i.e., small) jib. There’s no boom, but a spreader bar between the double backstays, so there’s no need to duck and weave to avoid head injuries, or worse, when tacking or jibing. The main furls into the mast, and the winches are electric. Witchway has added a spinnaker—well, it’s a cruising chute actually, which attaches to the bow instead of a guy or brace—so running it is simplicity itself. It has a sock to make getting it down equally simple.
Other points to note on the tech side: the keel is full length and the boat’s draft is only 5 feet 6 inches, so the vessel is one of the few bluewater yachts shallow enough to be taken through most of the European and U.S. canal systems. Displacement is 44,000 pounds, which includes 7,000 pounds of ballast. Freshwater tanks can hold 400 gallons. The two heads have holding tanks. There’s a workshop next to the engine room. Bow thrusters make docking and undocking very simple. Everything has been set up for ease of operation and comfort, BUT, and it’s a big BUT, combined with safety.
FUEL FOR FLEXIBILITY

And so to sea. In case of heavy weather requiring a run at speed, the crew decided to take four extra flexible fuel bladders, each with 52.8 gallons (200 liters). They were lashed to the deck and decanted into the tanks every few days, siphoning via a plastic valve and a hose for about 15 minutes each time—no spillage.
Because Witchway’s journey took place in late June and the Pacific hurricane season was approaching, the first leg was chosen almost due west from Ensenada to Hilo in Hawaii, instead of southwest to Tahiti. This took almost 14 days at sea, over a total of 2,202 nautical miles. Average speed was 6.55 knots over the leg, with the boat being motor-sailed to maintain the target daily distance of 160 nautical miles. Refueling and reprovisioning in Hilo took two days.
Leg two was Hilo to Apia in Western Samoa, again about 14 days at sea covering 2,279 nautical miles at an average of 6.78 knots. Three days later, Leg three took the boat from Apia to Suva in Fiji, covering 666 nautical miles in four days at sea at an average of 6.93 knots. After two days in port, Leg four took less than five days at sea from Suva to Noumea in New Caledonia, 801 nautical miles at an average of 160 miles a day. Two more days in port and Leg five began from Noumea to MacKay, Australia, 983 nautical miles in about six days, achieving 164 miles a day.
Some interesting points about performance: the trip took a total of almost 1,850 gallons (7,000 liters) of fuel to cover 6,931 nautical miles, or about .26 gallons (1 liter) per mile. Motor sailing was aimed at covering 160 miles a day, with the engine running at 1200 rpm to maintain this. Only on a few occasions was it necessary to speed up to escape weather, when the boat was pushed up to 8 knots and a bit more. Fuel consumption seems to reach an “economical cruise” optimum of about 7 knots at 1500 rpm (see table). This was below the turbocharger speed, so about once a day the engine would be run at sufficient speed to use the turbocharger, and thus burn away any carbon deposits resulting from incomplete combustion. Not much of a chore. Also on performance: everything worked for the entire trip. And when sailing, the boat would point to about 50 degrees off the apparent wind and hold a good speed.
So the world is available at a reasonable speed and a high degree of comfort, with a wide range of options available in terms of weather and seaway windows. Instead of running up and down coastlines, there are ocean passages that can be made, opening up a vast range of interesting times. Spoiled for choice, really. But that’s the virtue of the Mandarin 52 motorsailer.

TABLE

This is not a boatyard or engine manufacturer’s table; Witchway’s current owner supplied it after test runs conducted at the request of the author. The conditions under which the runs were made were:
1. No sails up 2. Weight: fairly light—fuel tanks 100-percent full, water tanks 50 percent, negligible stores 3. Winds variable SE 6 to 10 knots 4. Sea state 1 5. Prop: Fixed four-blade Michigan Wheel 28-inch diameter, 20-inch pitch (2-inch prop shaft) 6. Engine: Cummins Model 6BT5.9M rated at 220bhp at 2500 rpm

The boat was steered on a constant course of 279 T and the engine was run up to working temperature (82 degrees C). Then the engine was set at an initial 1000 rpm increasing by 100 rpm every four minutes.
TABULATION

RPM

Fuel Flow
U.S. gal/hr

Exhaust
temp deg C

Eng Room
temp deg F

GPS Speed
Knots

1000

.8
100
100
4.7

1100

1.0
125
102
5.3

1220

1.25
150
105
5.8

1280

1.3
190
108
5.9

1400

1.75
200
111
6.6

1500

1.85
220
113
7.0

1600

2.20
240
114
7.3

1700

2.5
250
115
7.4

1800

3.0
280
116
8.1

1900

3.3
300
117
8.4

2000

4.0
310
118
8.6

2100

4.75
340
119
9.0

2200

5.25
350
119
9.2

2300

6.10
350
120
9.4

There are some anomalies at various rpm that the owner put down to errors in the rev counter; some changes are insignificant compared to others. Two people recorded the readings, so there was no error in taking the readings.
CONCLUSION
1. Prop was matched well to this hull and engine, as no engine straining nor exhaust smoke nor excess exhaust temps were recorded. Slight prop “sing” noted, which is fairly normal at some harmonic revs—in this case between 1400 and 1700 rpm. 2. Clearly the most economical fuel consumption is between 1400 and 1600 rpm for about 7 knots, which would increase with sails up. This fairly well confirms Witchway’s consumption across the Pacific.
3. Increasing speed to 9 knots at about 2100 rpm doubles fuel consumption. 4. Increasing speed to 10 knots at about 2500 rpm triples fuel consumption. 5. Cummins’ quoted power output is at 2500 rpm. The rev counter showed a max of 2600 before reaching stops; hence the earlier comment that the rev counter may not have been precisely accurate.]]>

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