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Jon Ames
ProBoat/WoodenBoat
entry
competed with 58 entries from profes-
sionals, students, and amateurs from
all over the world. The
ProBoat/
WoodenBoat
panel of judges for
De-
sign Challenge II: More pleasure at 2
Gallons Per Hour
was aimed at inspir-
ing less-expensive, more fuel efficient,
and seaworthy designs. The entered
designs were to be capable of carrying
a family on overnight excursions. En-
tries were to meet the following crite-
ria:
■ Must be trailerable for afford-
able launching, over-the-road
transportation, and storage.
■ Max beam 8′; max length 40′
■ Minimum length 24′, stem to transom
■ Trailerable weight (with engine) should not exceed
3,500 pounds
■ Must burn less than 2 gallons per hour (7.6 l/hr),
maintaining a 10-knot cruising speed in a 2′ (0.6m)
chop and 15-knot breeze while carrying 800
lbs/362 kg (family of four). Favorable consideration
will be given for continued efficient fuel consump-
tion and good seakeeping abilities at speeds in ex-
cess of 10 knots
■ Must include at least spartan overnight accommo-
dations (berths, head, galley) for two adults and two
children
■ Must be a new design
■ Submissions should be the designer’s original, pre-
viously unpublished work, and include lines, pro-
files, sections, table of offsets, accurate weight
study, cost calculations, and performance predic-
tions.
Winners were selected in three
categories based on construc-
tion material: composite,
metal, and wood. Jon Ames’
30-foot
St. Joseph Sound
Launch
won the wood cate-
gory.
Jon Ames describes his win-
ning entry as follows:
On the west coast of
Florida there is a nice
little piece of water
called St Joseph Sound.
It has numerous spoil
islands, shallows,
beaches, parks, wildlife, all within a short cruise
from Clearwater or Tarpon Springs. A fuel-effici
weekend boat is just what is called for to enjoy
some wonderful family time exploring the sound
a leisurely pace. This boat was inspired by the c
lenge and the sound.
Of primary importance in this challenge was the
fuel consumption, so close attention had to be p
to hull shape and weight. I chose a semi-
displacement hull form optimized to operate at
speed/length ratio of 2. This in turn determined
other critical aspects of the design. Quarter-bea
buttock angle, prismatic coefficient, and center
buoyancy are carefully matched to the S/L ratio.
The D/L is very low, a result of limited fuel store
and simple outfitting. At this S/L ratio a round bi
reduces wetted surface and gives a softer ride.
Deadrise forward is high for easy entrance into
waves, but flattens out af
to reduce displacement.
This is not an offshore bo
but should serve comfort
bly in the bays and sound
of western Florida and th
Keys.
Interior accommodations
are sparse but sufficient
a small family. V berth fo
ward with porta-potti und
galley with sitting headro
and access to stove, iceb
and sink. Two small bert
under the bridge deck sui
Continued on Pg.