This
design will now be presented by Rainier Catamarans, LLC, and built to
the same exacting standards as our Rainier 500 sail cat. The design
team of this beautiful little trawler is from a naval
architecture firm known worldwide for cutting-edge catamaran design and
development.
We are proposing a line:
480, 550, 620, 680
etc., and larger projects are easily feasible.
The hull designs are already well -proven;
YOU ARE NOT A GUINEA PIG!
You are choosing a proven hull with
ONLY a trawler-style design on top, built by a LARGE, CAPABLE,
WELL KNOWN AND RESPECTED BUILDER.
Please contact C M I for more
details. EACH owner
will be able to choose a layout (we currently have only one drawn, but
this is just ideas put to paper), fit, and level of finish,
suitable to their needs.
The 480
If we assume that the 480 will be a
fairly heavy little ship - lets say she displaces around 23 tons in heavy ship
mode - i.e., full fuel, full water, full stores and
crew etc, then the fuel burn/power/speed figures should look
something like the following, if we use a pure displacement hull form.
|
Speed Knts
|
Installed
Power (Hp)
|
Litres per
nautical mile
|
Range
(nautical miles)
|
|
7.0
|
32
|
0.95
|
4221
|
|
7.7
|
45
|
1.20
|
3324
|
|
8.4
|
58
|
1.44
|
2779
|
|
9.0
|
74
|
1.71
|
2342
|
|
9.6
|
90
|
1.95
|
2051
|
|
10.4
|
128
|
2.56
|
1562
|
|
11.2
|
156
|
2.89
|
1384
|
|
12.4
|
189
|
3.19
|
1256
|
|
13.6
|
223
|
3.42
|
1171
|
|
14.7
|
254
|
3.60
|
1112
|
|
16.1
|
295
|
3.82
|
1048
|
|
17.3
|
333
|
4.01
|
997
|
|
18.5
|
370
|
4.17
|
959
|
|
19.7
|
416
|
4.40
|
908
|
|
21.0
|
479
|
4.76
|
841
|
|
21.8
|
553
|
5.28
|
757
|
DESIGNER's NOTES:
Some things to note:-
1) This is data scaled from
actual fuel trials on one
of our displacement cat designs – i.e., the ship has been scaled down
using
normal naval architectural scaling laws to determine resistance and
powering.
2) There may be some elements
that don’t scale
correctly. For instance, the propellers may be less efficient as they
get
smaller, or the trim of the boat may be more affected on a smaller
boat, which
could alter figures.
3) The range is from 4000 litres
(~1050 gallons) of
fuel, but does not include an allowance for rough sea conditions,
reserve on
arrival, genset fuel burn, etc.
4) We might use a
semi-displacement hull that is less trim and less immersion sensitive
than a
pure displacement hull, as well as offering more accommodation volume
in the demi-hulls.
This will offer similar fuel burn/power data at 7 – 9 knots and 17 –
22 knots, but will be not so good in the middle of the speed range.
Even then, it looks like our 23
tonne hull is probably
more efficient than a Fontaine Pajot 14 tonne hull – which seems to
have
a range of around 1000 miles at 7 knots from 1600 litres (420 gallons)
of fuel.
With our hulls at 23 tonnes I predict a range of over 1600 miles at 7
knots.
858.459.9114
C M I
Rand Hogen
