| Boat Specifications |
| Parameter |
Value |
Description |
| |
|
|
|
Loa |
27 ft., 8.23 m |
Length overall |
|
Lwl |
25.5 ft., 7.77 m |
Length at waterline |
|
SA |
400 sq. ft., 37.16 sq. m |
Total sail area of the Main and
Jib - 100% fore-triangle area only |
|
Boa |
13.67 ft., 4.17 m |
Beam overall |
|
Bcl |
10.41 ft., 3.17 m |
Distance between hull centerlines of a catamarn or the distance between
outrigger centerlines for a trimaran. Unless provided by the Designer
it will be approximated by the formulas: Catamaran (Bcl = Boa-Bh)
for a trimaran (Bcl = 0.95*Boa). |
|
Bh |
3.26 ft., .99 m |
Distance between hull centerlines
of a catamarn or the distance between outrigger centerlines for a trimaran.
Unless provided by the Designer it will be approximated by the formulas:
Catamaran (Bcl = Boa-Bh) for a trimaran (Bcl = 0.95*Boa). |
| Disp |
2.8 LT |
Displacement -- Designer's
target weight for a boat expressed in tons or, lacking that information,
the actual weight divided by 2240 lbs. |
| 6272.00 lb |
| 2844.93 kg |
|
Bcl/Lwl |
0.41 |
Ratio of Beam at the hull centerlines
(Bcl) to the waterline length (LWL). For catamarans, this should be
40% or greater to avoid wave interference between the hulls and subsequent
drag rise at speeds approaching hull speed. |
|
Lwl/Bh |
7.82 |
Waterline length to the beam ratio
of a single hull of a catamaran or the center hull of a trimaran. 16:1
High Performance Racer; 12:1 Racer; 10:1 Racer/Cruiser; 8:1 Cruiser.
The narrower hull will be faster, . The fuller hull will be slower,
but carry more payload for a given boat length. |
|
PI-C |
0.64 |
PI-C : A Classic indicator of
a measure of relative speed potential of a boat. It takes into consideration
Sail Area, Displacement and boat Length at Waterline. The higher the
number, the faster speed potential for the boat. PI-C = 0.5*SQRT( (Lwl*SA)/(Disp*2240)
) |
|
BSpd |
7.74 Knots |
Base Speed is an empirically-derived
indicator of the speed a given boat could average over a 24 hour period
under a variety of conditions. It can be used to compare speed potential
of one or more boats and has been used for handicapping boat races involving
a variety of boat types. "Base Speed: A Simple Measure for Estimating
Multihull Performance", Multihull International,No. 225,(APR'89) pp.108-110.
Base Speed=1.7*(Lwl^0.5)*(SA^0.352)/((Displacement*2240)^.253) |
|
BN |
1.09 |
The Bruce Number is a power-to-weight
indicator for relative speed potential for comparing two or more boats.
It takes into consideration the sail area of the main and jib, no overlapping
sails, and the displacement. Chris White, "The Cruising Multihull";
1997 International Marine, Camden, Maine, states that a boat with a
BN of less than 1.3 will be slow in light winds, and a boat with a BN
of 1.6 is a boat that will be reefed often in offshore cruising. Derek
Harvey, "Multihulls for Cruising and Racing, 1991, International Marine,
Camden, Maine, states that a BN of 1 is generally accepted as the dividing
line between so-called slow and fast boats. Bruce No. = SA^0.5/(Displacement*2240)^.333 |
|
SA/D |
18.82 |
The SA/D ratio is similar to the
Bruce Number, giving a power-to-weight ratio type figure for comparing
two or more boats. Higher numbers indicate faster boats for a given
length. However in this ratio, unlike the Bruce Number, main and genoa
or any combination of sail area can be used. When comparing any two
boats one should ensure that both the SA and displacement, including
planned payload, are equivalent, to get a realistic comparison. SA/D
= SA/(Displacement*2240/64)^.666666667 |
|
Texel |
146 |
The Texel Rating provides handicap
numbers for widely varying boats sailing together in a race. The formula
is essentially the inverse of the Base Speed formula with constants
applied to make the numbers useful. The Texel Rating permits the calculation
of time to sail a given distance. Thus, a boat with a higher Texel Rating
can be expected to take longer from start to finish of a race than one
with a lower TR. TR = 100/(0.99*(Lwl)^0.3*(SA)^0.4/(D)^0.3)*K in which
K is a correction for catamarans vs. trimarans, based on the equation,
K = 1/(0.19*SA^0.4/D^0.36+0.91). If K is greater than 1, use the calculated
value. If K is less than one, use the value 1. K is always one for trimarans. |
|
SI-CM |
2.44 |
This figure is an indicator of
the resistance of a boat to sideways capsize for comparison with other
boats. This formula only considers static Forces, not dynamic forces
such as hull shape, wind, and waves. Therefore it should be considered
a "Figure of Merit". "Theory and Statistics for Cruising Multihulls"
by Calvin Markwood, Multihulls Magazine, Vol. 23, No. 2, (MAR/APR 1997),
pp. 51-59 Article. The higher the number, the more resistance to sideways
capsize. SI-CM = 1000*((Displacement*Loa*Bcl)/((SA)*(SA+15*Loa)) |
|
SSpd |
22.34 Knots |
The Stability Speed figure
is an indicator of the wind speed at which the windward hull of a catamaran,
or the main hull of a trimaran, will begin to lift. This formula only
considers static Forces, not dynamic forces such as hull shape, wind,
and waves. SSpd = 8.23805*((0.5*Bcl*Disp*2240)/(SA*Hce))^0.5 Multihull
Designs" by John Shuttleworth Yacht Designs, 1998, p. 37. |
| |
|
|
