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Multihull Dynamics, Inc
First Order Trend-Line Analysis Comparison: BROADBLUE 38 FOUNTAINE PAJOT ATHENA 38 LAGOON 380 MAXIM 380 MKII - VOYAGE 380 Compiled by MDI Staff 03/12/2011
Basic Specifications:
Length Over All Length at Waterline
BROADBLUE 38 38.00ft, 11.58m 34.50ft, 10.51m
FP ATHENA 38 38.45ft, 11.72m 38.00ft, 11.58m LAGOON 380 38.08ft, 11.61m 36.08ft, 11.00m
MAXIM 380 38.70ft, 11.80m 37.60ft, 11.46m
MAXIM 380 MKII 39.00ft, 11.89m 38.32ft, 11.68m
Beam Over All Beam Centerline Beam Hull BROADBLUE 38 17.42ft, 5.30m 14.32ft, 4.36m 3.09ft, .94m
FP ATHENA 38 20.70ft, 6.31m 16.95ft, 5.17m 3.71ft, 1.13m
LAGOON 380 21.75ft, 6.63m 17.41ft, 5.31m 4.34ft, 1.32m
MAXIM 380 20.60ft, 6.28m 16.73ft, 5.10m 3.87ft, 1.18m
MAXIM 380 MKII 20.57ft, 6.27m 16.00ft, 4.88m 3.72ft, 1.13m
Displacement Sail Area (main & jib only)
BROADBLUE 38 3.40LT, 7617lbs, 3455kg 748sqft, 69.49m2
FP ATHENA 38 5.4LT, 12096lbs, 5487kg 789sqft, 73.30m2
LAGOON 380 7.0LT, 15725lbs, 7133kg 740sqft, 68.75m2
MAXIM 380 5.8LT, 12992lbs, 5893kg 915sqft, 85.01m2
MAXIM 380 MKII 5.9LT, 13216lbs, 5995kg 915sqft, 85.01m2
Beam Centerline/Length WL (ratio) Length WL/Beam Hull (ratio)
BROADBLUE 38 .42 11.16
FP ATHENA 38 .45 10.24 LAGOON 380 .48 8.31
MAXIM 380 .44 9.72
MAXIM 380 MKII .42 10.30
Bridgedeck Height Bridgedeck Clearance vs. Nominal Height
BROADBLUE 38 Data Not Available Data not Available
FP ATHENA 38 .29in, 73.66cm 0in, 0cm
LAGOON 380 Data Not Available Data Not Available
MAXIM 380 Data Not Available Data Not Available MAXIM 380 MKII 23in, 58.42cm -6in, -15cm
Performance Indicators:
SA/D BN Base Speed PI-C Texel
BROADBLUE 38 30.92 1.39 10.69 Not Avail 115
FP ATHENA 38 18.86 1.09 9.06 .65 144
LAGOON 380 23.96 1.23 10.17 .79 127 MAXIM 380 26.49 1.29 10.46 .81 122
MAXIM 380 MKII 26.19 1.28 10.52 .81 122
Stability Indicators:
Stability Index –CM Stability Speed BROADBLUE 38 1.88 14.79
FP ATHENA 38 4.80 23.63
LAGOON 380 3.27 19.46
MAXIM 380 2.74 17.80
MAXIM 380 MKII 2.68 17.57
Detailed explanations of terms, formulas and interpretations are available on the
Technical pages of the website:
http://www.multihulldynamics.com/news_article.asp?articleID=34
Trend Line Graphs and Cals Eval:
MDI reports comparison data with other vessels selected by Calvin H. Markwood.
In the Custom Multihull Eval the comparisons are offered in two ways:
(1) In “Cal’s Evals” Mr. Markwood gives related LWL vessel AVERAGES.
(2) The second method is by the Trend-Line graphs below. We use the Trend
Line of the Type Database, i.e. Catamaran or Trimaran as appropriate. At
the time of this report there are 856 catamarans in our Database used to
develop the Catamaran Trend Lines.
These Trend Lines are not averages or means, but rather are statistical evaluations
that give the “relationship” of this multihull to other catamarans of similar waterline
length in the Database. The 5 stars on the graphs represent the following boats:
Blue Star = BROADBLUE 38; Red Star = FOUNTAINE PAJOT ATHENA 38;
Black Star = LAGOON 380; Gold Star = MAXIM 380 and the Green Star =
MAXIM 380 MKII.
For a more in depth understanding of these graphs and their results you may wish
to read the Technical pages of the MDI website.
The orders of the graphs are: power ratings, performance and stability formula
predictions.
1. The power graphs are: Bruce Number (BN) and Sail Area/Displacement
Ratio (SA/D)
2. The performance graphs are: Base Speed (BSpd) and Texel Rating (TR)
3. The stability graphs are: Stability Speed (SSpd) and Stability Index (SI-CM)
**Due to differences in software and printers there may be a slight variance
of where a multihull is located on the Trend-Line graphs. The user of this
report may use the data above and review the plots to insure accuracy of a
multihull location on the graphs.
Power Graphs:
Note: Rigging categories from Chris White "The Cruising Multihull"
BROADBLUE 38; FOUNTAINE PAJOT ATHENA 38; LAGOON 380;
MAXIM 380; MAXIM 380 MKII
Performance Graphs:
BROADBLUE 38; FOUNTAINE PAJOT ATHENA 38; LAGOON 380;
MAXIM 380; MAXIM 380 MKII
BROADBLUE 38; FOUNTAINE PAJOT ATHENA 38; LAGOON 380;
MAXIM 380; MAXIM 380 MKII
Stability Graphs:
BROADBLUE 38; FOUNTAINE PAJOT ATHENA 38; LAGOON 380;
MAXIM 380; MAXIM 380 MKII
** Stability Speed (SSpd): This formula does not take wave action, shortening of sail or
hiking-out into account. It includes a 40% safety factor for wind gusts but does not
compensate for wave effect. For more information on Stability Speed read the Technical
page on the website.
Another way to consider this result: Sailors who have sailed this vessel report no difficulty
with stability at this wind speed. However Shuttleworth’s formula takes into account a
sudden gust of 40% above this SSpd. His formula determines when it is time to reef down
from the standard main and jib sail area carried for a boat to remain secure, in preparation
of the possibility a sudden wind gust; it is the safety factor. Of course this is the difference
between monohulls and multihulls; monohulls reef to the prevalent winds, multihulls reef in
anticipation of gusts.
BROADBLUE 38; FOUNTAINE PAJOT ATHENA 38; LAGOON 380;
MAXIM 380; MAXIM 380 MKII
Stability Index (SI-CM): This not a real world number; rather it is an abstract number that
allows stability between two different multihulls to be compared. It is referred to as a
“Figure of Merit”.
Detailed explanations of terms, formulas and interpretations are available on the Technical
pages of the website www.multihulldynamics.com
Cal's Eval:
Maxim 380 MKII - Voyage 380 The Maxim 380 Mk II, also sold as the Voyage 380, was updated in 2004 by stretching the boat and increasing the displacement aft to accommodate larger engines and an improved aft cabin layout. According to the Maxim Yachts web site, other improvements were made to make on deck movement safer and cockpit living more attractive. There is considerable information and drawings of this boat on their website. The Multihull Dynamics, Inc. (MDI) evaluation of the boat in comparison with the averages [shown in brackets] of 25 cruising
catamarans with waterline lengths in the 38 foot range is as follows: Displacement: 5.90 tons [5.83 tons (range for 25 boats is 3.5 to 11.0 tons)] Length Overall: 39 feet [40.23 feet (range is 38.06 to 46.0 feet)] Length at Waterline: 38.32 feet [38.29 feet] Sail Area (Main plus 100% fore-triangle): 915 sq. ft. [908 sq. ft. (range is 684 to 1130)]
Sail Area/Displacement Ratio: 26.19 [27.24] Beam between hull centerlines: 16.0 ft. [18.21 ft.] Bridgedeck Clearance 23 in. [29 in. is nominal for 38 ft. LWL catamarans] Lwl/Bh ratio: 10.3 [10.31] Base Speed: 10.52 knots [10.31 (range is 9.58 to 12.31)] Texel Rating: 116 [115] Bruce Number: 1.28 [1.30] Stability Speed: 17.49 knots [18.68 (range is 13.64 to 22.93)] The Maxim 380 falls very close to the average values for catamaran cruisers its size in all areas except beam between hull centerlines and bridgedeck clearance. In fact, it falls nearly directly on the trend lines for 708 cruising catamarans ranging from 20 feet to 130 feet long in the MDI database. The smaller than average beam between hull centerlines accounts for the
lower than average Stability Speed. The low Bridgedeck clearance may portend bridgedeck slamming when sailing into waves.
With the Lwl/Bh ratio of 10.3, it is in the cruising category by Charles Kanter’s method of categorizing multihulls. The boat has spade rudders and low aspect ratio keels. The latter of which further cements it into the cruising category. The Maxim 380 hulls have a trapezoidal shape above the waterline with rounded corners below. The departure from semicircular below the waterline provides increased displacement without increasing the waterline beam.
Calvin H. Markwood Engineering Analyst Multihull Dynamics, Inc.
Contact Cal: [email protected]
Photos and Layouts:
BROADBLUE 38
FOUNTAINE PAJOT ATHENA 38
LAGOON 380
MAXIM 380 MKII – VOYAGE 380
Notes:
1. Only one “Cal’s Eval” is available for the listed boats in this
report, the MAXIM 380 MKII – VOYAGE 380
2. It is important to remember that this data is calculated from the basic data reported by the designers and manufacturers of these boats. Variance in production techniques and products can affect Displacement. Displacement is a major factor in these calculations.
This report can help narrow a more intensive investigation of specific boats. It is highly recommended that the boat(s) be weighted prior to purchase. If the weight of any of these boats is found to be different than we have reported here, Multihull Dynamics, Inc will re-calculate all formulas based on the new reported Displacement data at no charge. We simply request a copy of the certified document showing the weight of the boat.
3. Catamarans in our database whose Length Over All is 38 feet, 11.6M, have an average weight of 5.3LT (Long Tons),
an average Bruce Number (BN) of 1.3 and an average Base Speed 10.32. While boats will vary from these averages, careful consideration should be given to boats whose results are significantly different from these averages.
MDI Policy:
Multihull Database
Multihull Dynamics, Inc. reserves the right to list boats for which specification information is
published in magazines, brochures, websites and other public media. Where possible, we
augment published information with specification data provided by the designers and builders.
Where invitations to provide this information are declined, we use estimating methods described
in the article Analysis and Comparisons of Cruising Multihulls 2008 to provide the missing information.
Disclaimer: Neither Multihull Dynamics, Inc, nor any of its employee’s guarantees in any way the data in
neither this report, nor the calculations derived from use of any formulas on this report, including those services
purchased.
Terms of Use: Visit the website for an explanation of your previous agreement to “Terms of Use”.
Copyright 2004-2011 Multihull Dynamics Inc. All rights reserved