What a Difference a J
Makes.
Now it's possible to sail fast with just a friend or
two as crew. After all, isn't this how we sail most of the time on a day's
sail or when cruising? Rarely is the gang aboard to hold the boat down or
fly a spinnaker.
The measure of a good sailboat is how well it sails upwind and downwind with only 2-3 people aboard. The goal is VMG,
Velocity-Made-Good, straight into the wind or away from the wind, considering both speed
and sailing angle. Many of the modern integrated instrumentation systems can display this
data, or you can use a set way-point to windward on a GPS to come up with the number.
Good short-handed VMGs are when a "50-something" husband & wife
jibe a J/105 (34.5 ft.) with asymmetrical through Woods Hole against the current, while
others motor. Or, if you can beat upwind in steep waves doing 6.8 knots with a VMG of 5
knots in 18 knots of wind!
Safe, Fast & Easy
Flying an asymmetrical spinnaker from a retractable, carbon-fiber bow sprit is
a one person job. By using a cockpit-operated snuffer, no one has to be on deck when the
spinnaker is flying, being jibed or doused. To jibe, simply let off one sheet and pull in
the other. Downwind VMG is doubled. Result? Less motoring and more sailing.
It's safer. One corner of the spinnaker (the "tack") is always secured
to the bowsprit, eliminating wild oscillations. The sail has more slope to its leading
edge with a center-of-effort located further forward and lower. Wind gusts lift the bow,
propelling the boat forward with finger-tip control. No more "white-knuckled"
round-up broaches.
Speed from the asymmetrical's greater power pushes the apparent wind 30-50
degrees forward of the true wind direction. In light air and lumpy seas, the sail's added
power steadies the boat. Deep sailing angles (160-170 degrees True Wind Angle) are
achieved in a breeze. The luff, which is 8% longer than the straight line distance from
tip of the sprit to halyard exit on the mast, rotates to windward as the sheet is eased -
projecting area to the wind like a conventional spinnaker when pulled back by a pole.
That Feel
The new Js instill a sense of confidence, freeing one from anxieties. Even when planing at
10+ knots, one feels in total control. There's less work. Guests aren't pressured into
unfamiliar tasks. Fewer orders are needed. It's more fun...like a good sports-car, turning
as if it were part of you. Not with sluggish delay. But with a smooth, even response -
around crests, down waves and through crowded harbors.
Mainsail Only
J's sail well flying any sail combination you feel comfortable with. For
harbor-cruising or heavy winds, an unreefed main is the answer. If the boat sails 6+ knots
under main alone, why bother with large overlapping jibs? Visibility is improved. The big
main is a bonus for "cruising canvas" races. And, it takes one person to sail
the boat. High wind mode is a flattened mainsail with open leech, achieved by tightening
backstay, cunningham, vang and outhaul. These adjustments are quicker and easier than
reefing. The jib can be rolled up and forgotten.
34% Upwind VMG Gain?
Hull design, rig, sailing length and weight location greatly affect VMG. You see many
cruising boats motoring upwind in both light and heavy air. Why? Not enough sailpower
for light air or stability for a breeze. For example, the J/109 (35 ft.), sailing upwind
at 7.2 knots, 38 degrees from the true wind (25 degrees apparent) will have a VMG
of 5.7 knots. This is 15% faster than boat X sailing 7 degrees further from
the wind at 7 knots with a VMG of 4.7 knots. And, it's 34% faster than a classic cruiser
doing 6 knots with an upwind VMG of only 4.2 knots. These differences are inescapably
locked in by design and construction.
Low Center of Gravity
Good upwind VMGs are only possible with a low, vertical center of gravity (VCG). Top-heavy
boats roll and pitch. This motion disturbs water flow around the boat and airflow past the
sails, not to mention equilibrium of the crew on deck. The lower the weight of the boat
relative to its waterplane, the greater the stability, the more sail that can be carried
and the smoother the motion. This explains a J's smooth, stable ride through waves. The
VCG is well below the waterplane.
Resin Infusion Process
You get what you pay for. Low VCG is achieved by
light, strong construction of what's above the water. Since 1994 most J
models benefit from the innovative SCRIMP resin-infusion process.
End-grained, aircraft-grade balsa-core laminates have structural GRP skins
with 65-70% glass content, or the equivalent of custom high-tech, oven-baked
pre-pregs.
High Performance Rigs
The best place to reduce weight is aloft. All spars are custom-designed for
J Boats, race-tested and abused to insure reliability with a good safety
margin built-in. Running backstays aren't required. For models like
the J/122 and J/133, a carbon-fiber mast is specified to further optimize
upwind stability and VMG for short-handed cruising. These custom-engineered,
one-piece, autoclaved spars by Hall Spars have a luff track designed for
low-profile and low-friction slides. The 120-130 pound weight saving aloft
is equivalent to having two invisible 200 pound genies sitting on the
weather rail to improve performance.
Ballast & Shoal Draft
The best place to add weight is in the keel. A lead keel, fixed under a
structural molded sump, having much of the weight in a bulb at the bottom,
serves to optimize a boat’s stability without adding excess draft. J’s
combine low VCG ballast with quality construction - especially important
when opting for a shoal draft keel. Cruising "J’s” with shoal draft keel
routinely outperform longer, deeper draft cruising boats. Before deciding on
this option, consider that the need for shoal draft may be a function of
speed. A fast boat, that easily sails 50 miles in a day, puts more deep
harbors in range than can be visited in a year.
Horsepower
Sails are the horses. A light boat with clean lines and good stability can carry the sail
power needed for lively performance. There's no need for tall, scary rigs with heavy sheet
loads and winches. Sail Area to displacement (SA/[DSPL/64]^.67) is a good indicator of how
much horsepower the design can handle and what its speed potential might be. Look for
ratios over 20. The J/122 is at 23%.
Low Resistance
Too much weight usually means too much wetted surface (WS). Like brake shoes. The more WS
there is relative to sail area, the quicker you stop. A good SA/WS ratio is critical for
performance in light air conditions. Among 40 footers, J/122's ratio of 3.1 is
FAST.
A boat with a 2.0 would be "glued." Then there's form drag. It's usually faster to be long and narrow. But only when
combined with greater stability and sail power. A length (LWL) to beam (BWL) ratio greater
than 3 is desirable for good directional tracking in waves. Then, oversized keel, skeg or
rudder surfaces aren't necessary. A long canoe tracks, a pram spins. J/122 has a healthy
3.6:1 ratio with flared topsides. Flare slaps waves down and keeps the crew dry.
Vertical-sided hulls bounce waves up on the crew.
Speed Rating
The rated speed of most sailboats is published. Order a copy of PHRF Handicaps from US
SAILING (401-683-0800). It's how we know the projected speed of a J/120 with genoa will be
30 seconds per mile faster than a Sabre 42 - more than the length a football field after 8
minutes of sailing! Or, that her all-round speed will equal boats which are nearly 20 feet
longer, such as a Swan 57, Hinckley 59 or Deerfoot 62. An often overlooked benefit of such
speed is the help it gives you in route-planning when dealing with weather systems.
Your Next Boat
Now more than ever before, differences between sailboats are greater than differences
between golf clubs, tennis rackets, skis or cars! Performance is the reason you don't see
wooden or solid fiberglass tennis rackets, skis or golf clubs anymore. A fast new
"J" can make a beginner look very good, leaving the experts far astern with
little solace that slow is easier or more comfortable. It could take years, owning and
sailing all types of boats, to learn that good design and high quality composite
construction makes so large a difference. Or, you can make the most of your time and
dollars by acquiring what we've learned and are designing into every new
"J."
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