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Subject: TWL: Motorsailers?
LRZeitlin@XXX.XXX
Date: Tue Nov 13 2001 - 13:17:46 EST
All this discussion about motorsailers and trawlers with sails may be
unfamiliar territory to confirmed powerboat owners. I offer this melange of
opinion and fact to help confuse the issue.
It is hard to be precise about the characteristics of a motorsailer. Francis
Kinney, who revised "Skene's Elements of Yacht Design", gives a general
insurance company rule that says a motorsailer is a yacht with enough engine
power to achieve hull speed AND enough sail power to claw off a lee shore if
the power fails. He states that insurance companies conclude that this
requires at least a sail area equal to the LWL squared, divided by two. Thus
an adequately powered sailboat with a 40 ft. LWL should, for insurance
purposes, have at least 800 sq. ft. of sail area to be classed a motorsailer.
Less than that and it is basically a powerboat with steadying sails. Juan
Baader, in "The Sailing Yacht" has a much more pragmatic rule. He says that
if a yacht is faster under sail than under power it is an auxiliary powered
sailboat. On the other hand, if it is faster under power than under sail, it
is a motorsailer.
Current useage categorizes motorsailers by hull type and deck configuration
since most modern yachts are fully powered. There are basically two types of
motor sailers available. The first is a full powered sailing hull with an
enlarged deck house that retains most of the virtues and some of the vices of
a pure sailing hull. The power is usually much more than enough to push the
boat to hull speed and to slog to windward in a gale. This usually means at
least 5 hp per 500 lbs of displacement. The Jensen Cal/Cruising 46 might be
considered an older representative of this class. The second type is a
displacement trawler or fishing hull with a sail rig. The Fisher line of
boats from GB are of this class. They are powered to cruise on engine alone
and usually turn a big three bladed prop through a reduction gear. Basically
they can be considered motor trawlers with sailing assist. They have moderate
to heavy displacement hulls with full keels and relatively shallow draft.
Pointing ability and clawing to windward are not their strong points. All
current motorsailers feature a pilothouse with full headroom and an internal
helm. In fact this feature almost defines the class. Several manufacturers,
including Pacific Seacraft, build boats with identical hulls and differing
deck moldings. Those with a pilot house are called motorsailers, those
without are called auxiliary powered sailboats. Willard has, in the past,
offered the Willard 30 trawler in motorsailing configuration and once built a
Willard 40 with a mast. The type is much more popular in Northern Europe
where typical boating conditions are such that most American yachtsmen would
be heading for the nearest bar in search of a hot toddy.
As the (sailing) population ages, it is likely that the proportion of
motorsailers to cruising sailboats will increase. To quote Baader, "A well
balanced motorsailer combines excellent seaworthiness with good sailing
qualities. Older yachtsman tend to turn toward motorsailers, since, although
they have not lost their enthusiasm for sailing, they are more exacting with
regard to comfort below decks and like to have more auxiliary power which
makes them independent of the sails for difficult maneuvers or in bad
weather." Many TWL members have already gone one step further and have opted
to dispense with the rags entirely in favor of trawlers.
Now for the facts:
We have owned a Willard Horizon motorsailer for nearly a decade. The Horizon
is essentially the Willard 30 trawler hull with a moderate sailing rig, the
ultimate in get home emergency power. It appeals to the aging sailor, like
myself, who doesn't want to give up rags and lines entirely.
The Willard Horizon has a full displacement hull, powered by a Perkins 4-107,
driving a three blade 18" x 14" prop through a 2.57 reduction gear.
Displacement is 15,000 lbs, including 4000 lbs of stabilizing keel ballast.
Hull speed is almost exactly 7 knots although the boat will probably squeeze
out another knot when racing for a bridge. Comfortable cruising under power
alone is 6 knots at a shade under 2100 rpm engine speed. Continuous rated
power of the Perkins is obtained at 3000 rpm so a good deal of reserve is
left in hand and the engine is lightly stressed. Based on our experience, at
a 6 knot cruising speed fuel consumption is .82 gal/hr. If the speed is
dropped to 5 knots, the onboard 120 gallon fuel supply permits a 1000+ nm.
range under power. This motorsailing tactic may be bad for diesel longevity
but a few minutes of high power every day tends to blow out the carbon. The
boat still has its original engine, a tribute to the durability of the
Perkins design.
The hull shape is vaguely similar to a Colin Archer turn-of-the-century
lifeboat with a high bow and a canoe stern. Like the Colin Archer designs,
the Willard has a very good sea keeping characteristics, a necessity since it
cannot outrun any storm. It is certainly seaworthy but not altogether
comfortable in bad weather.
I was originally attracted to the Horizon model because it appeared offer an
easy transition to the trawler world. I was certainly too optimistic. The
installed sailing accomodations are rudimentary and the sailing performance
is roughly on a par with Columbus' caravels. Still, with the sails up and the
boat heeling in a brisk wind, my Horizon looks very "yar" and I often get
compliments on its appearance. The sails also minimize rolling in beam seas,
another problem oft cited by trawler owners.
The practice of sailing takes some relearning. First, the drag of the prop is
so great that sails alone move the boat at only 4 to 5 knots in 15 kt.
reaching winds. Pointing is similarly poor. Sailing closer than 60 degrees to
the wind is a chore. Running the engine at moderate speed when sailing makes
all the difference. This fully compensates for prop drag and provides enough
power for easy maneuvering in gusty winds. The sails keep the boat stable and
the reaching speed increases to 6 kts. Fuel consumption is less than 70% of th
at required to maintain 6 kts on power alone. I am not a fan of CPPs on most
trawlers but I would like one for this boat. Certainly it would sail a lot
better.
Despite the marginal sailing performance, we have found the sails are useful
for emergencies and for dramatically extending cruising range. Under both
sail and power in favorable winds, fuel consumption drops to only .3 gal/hr
at 5 kt and theoretical cruising range is extended to 2000 miles. The
prevailing westerlies on the East Coast permit long coastal motorsailing
cruises with the wind abeam. Using this motor sailing technique we made it up
the ICW, inside and outside, averaging better than 6 kt on 120 gallons of
fuel.
I understand long range was the original idea of Willard's sail rig. The
Horizon was intended for brave souls wanting to take the inner passage to
Alaska where diesel stops are few and far between. The motorsailer's forte is
extended cruises to remote anchorages for a reasonably adventurous crew. Here
the seaworthiness and self contained nature of the boat pay off. The
conservative nature of the mechanical plant of most motorsailers permit
substantial maintenance to be carried out by the owner. The downside is, of
course, that rigging and sails must be maintained as well.
I must confess that were I to attempt the circumnavigation that the Nordhavn
40 is undertaking, I would rather be in a well equipped motorsailer, not
necessarily my own. Sail assistance makes for economical operation, long
range, and ultimate peace of mind. The wind may be uncertain but it will
eventually blow in the right direction. Fuel depots and mechanical spares may
be hard to find in mid-Pacific. Many TWL listees have reported inconvenient
cruise delays waiting for that vital part to arrive. You may well remember
that the Savannah, the first steamship to cross an ocean, had a full sailing
rig. Tradition is not to be entirely ignored.
The basic problem of the motorsailer is that it requires a psychological
straddle on the part of the owner. A motorsailer requires that the skipper
possess the attitudes and skills of the power community some of the time and
those of the sailng community some of the time and mix the two the rest of
the time. Most owners lean one way or the other. Comparatively few owners
seek the middle ground.
Larry Zeitlin
PUFFIN
Cortlandt Manor, NY
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