lesson 6 canoes, kayaks, pontoon boat and inflatables · lesson 6 canoes, kayaks, pontoon boat and...
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Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
1
Canoes, Kayaks, Pontoon Boats and
Inflatables
Capacity and flotation for canoes and kayaks and pontoon
boats are based on displacement. Inflatables though, are
based on interior volume of the air chambers, which easily
converts to displacement.
USA: The Capacity and flotation parts of the Federal
Regulations for recreational boats do not cover canoes and
kayaks, inflatables, and pontoon boats. They are excepted
from these regulations.
ABYC Standards and Technical Information Reports For Small
Craft include all of these. http://www.abycinc.org
H-28 inflatables
H-29 canoes and kayaks
H-35 pontoon boats
In Canada these are covered in TP1332.
http://www.tc.gc.ca/BoatingSafety/regs.htm
Section 4, Hull Design Requirements.
Sub Section 4.3 covers Capacity and flotation for multihull
vessels, that is, pontoon boats.
Sub Section 4.4 covers Capacity and flotation for
inflatable boats.
Canoes and kayaks are not included as long as they are
manually propelled. If they are rated for mechanical
propulsion then the provisions that cover monohull vessels
apply and are found in 4.1.
UK & EU: The RCD applies to all EU states and territories:
Recreational Craft Directive. The RCD is derived from the
ISO standard 12217-3. Stability and Buoyancy for Boats of
hull length less than 6m.
RCD, A.3.2 and A.3.3 Stability and Freeboard and Buoyancy
and Flotation: For boats up to and including 6 metres hull
length.
Canoes and Kayaks are specifically excepted from the RCD.
However if a Canoe is designed to be powered then it is
covered by the RCD as a monohull boat.
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
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See the Royal Yachting Association,
RCD guidelines.
http://www.rya.org.uk/KnowledgeBase/technical/reccraftdir.h
tm.
Australia: National Standard for the Australian Builders
Plate for Recreational Boats, applies to inflatables but
does not apply to canoes and kayaks. It references ABYC
standards, and ISO standards http://www.nmsc.gov.au/#s and
states that the builder must comply with any one of these
standards.
Definitions:
Canoes and Kayaks. The following is the ABYC definition of
canoes and kayaks. The US Coast Guard does not have an
official definition. They use the ABYC definition.
Canoe - A watercraft, designed to be manually propelled, with or without provision for
auxiliary power, with neither end having a transverse dimension greater than 45% of its
maximum beam.
Canoe Length Maximum Beam
14 ft. (4.25m) or less 1/3 Canoe Length
over 14 ft. to 16 ft. (4.9m) 1/4 Canoe Length
over 16 ft. (over 4.9m) 1/5 Canoe Length
Kayak – A watercraft designed to be manually propelled, with or without provision for
auxiliary power with the occupant intended to be seated with legs 90° from the torso.
These boats may have a provision for sealing the opening to the bodies of the occupant or
may be of a sit-on-top style.
Inflatable Boats: A boat that achieves all or part of its
intended structure, shape and buoyancy through the medium
of inflation.
Rigid inflatable boat: (RIB or RHIB) An inflatable boat
with a portion of the hull constructed as a rigid unit and
another portion that all or part of its intended structure,
shape and buoyancy through the medium of inflation.
Pontoon boat: A rigid structure connecting two separate parallel
buoyancy chambers, or pontoons, also often referred to as logs. Each
of the pontoons may have one or more separate sealed chambers.
Although boats with two pontoons are the most common,
sometimes a third pontoon is added for increased capacity.
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
3
Canoes and Kayaks:
Capacity:
The following do not apply to canoes or kayaks designed
specifically for whitewater or inflatable canoes and
kayaks. See the next section for inflatable canoes and
kayaks.
The capacity of a canoe or kayak is determined by first
finding the displacement weight. You can determine
displacement weight by the same method as in lesson 2,
using Simpson’s rule, or by test, by placing weights in the
canoe until water comes aboard. Or alternatively, by
filling the canoe with water and measuring how many gallons
(or liters) it takes.
The maximum capacity is
D = Displacement weight
Wc = Weight of the canoe or kayak.
W =.40 X (displacement weight – weight of the boat)
W = 0.40 (D – Wc)
The weight of the canoe does not include the weight of an
outboard motor if the canoe is rated for mechanical
propulsion. See Appendix A Table I for motor weights
Persons capacity weight equals the maximum weight capacity
or less. If rated for an outboard it equals maximum weight
capacity less the weight of the engine, portable fuel tank
and battery. For boats rated for an engine see Table 1 for
maximum horsepower ratings and weights.
Persons capacity = Persons weight + 32 /141. (rounded to
nearest whole number.)
C ≤ W - (Wm + Wb)
W = Maximum weight capacity
Wm = Dry weight of engine/motor and controls
Wb = Dry weight of battery from Table II (see Appendix A)
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
4
Flotation.
As with other boats the amount of flotation is determined
by finding the amount to float the boat, the people and the
engine, if rated for one.
First find the swamped weight of the canoe or kayak.
Ws = Wc x K
Ws = (___) x (___) = _____ pounds
Ws = Weight of canoe X conversion factor K, for the
material the canoe is made of. See Appendix A Table III For
conversion Factors.
Where: Wc = dry weight of canoe or kayak and K = conversion factor for materials from
Table III
S = Swamped weight of the motor
C = Persons capacity Weight
The amount of flotation needed is:
Wf = Ws + S + 0.1C
If no motor then
Wf = Ws + 0.1C
The cubic feet of flotation is:
F = Wf / B
B = the amount of buoyancy provided by the flotation.
For two pound density foam it is 60.4 in fresh water. (1000
kg/m3)
Flotation material needs to be located symmetrically around
the length of the canoe. If the canoe has a motor then at
least 50% of the flotation for the motor must be in the aft
one third of the canoe (that is the end where the engine
is)
Flotation:Example
A polyethylene canoe weighs 68 lb
The persons Capacity C is 494 lb
Length = 15 feet (4.6 m)
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
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Beam = 35.5” (90.0 cm)
Weight = 68 lb (30.8 kg)
This is a manually propelled canoe and has no provision for an
engine.
The displacement weight is achieved by loading the canoe
D = 1302 (590.6 kg)
W = .40 (D-W) = .40 (1302 – 68) = .40 (1234) = 493.6 (224 Kg)
C = W = 494 lb
Persons = 494 + 32 /141 = 3.7 or 4
Ws = Wc x K (Ws = swamped weight of canoe)
K for Polyethylene from Table III = 0.56
Ws = (___) x (___) = _____ pounds = 68 lb x 0.56 = 38
The amount of flotation needed is:
Wf = Ws + S + 0.1C (for boats with a motor)
If no motor then
Wf = Ws + 0.1C = 38 + 0.1 (494) = 87 lb (43.54 kg)
The cubic feet of flotation is:
F = Wf / B = 96 lb/60.4 lb/cu ft = 1.59 cu ft (39.5 Cu cm)
Inflatable Canoes or Kayaks:
Maximum Weight Capacity – The maximum weight capacity
marked on an inflatable canoe or kayak shall not exceed
three-quarters of the total volume of the main buoyancy
chambers in cubic feet, times 62.4, less the canoe or kayak
weight in pounds
Mwc = .75D-W = Maximum Weight Capacity
D = Displacement = total volume of the air chambers times 62.4.
W = Weight of the canoe or kayak.
ABYC requires that inflatable canoes or kayaks have at least two
chambers if under 12.5 Ft. (3.81m) or three chambers if 12.5 ft
(3.81m) or more.
The Canoe or kayak must be capable of supporting 50% of the maximum
weight capacity with the largest air chamber deflated. So, the
amount of flotation provided by the remaining inflated air chambers
must be at least;
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
6
0.50(Mwc) /62.4 = cubic feet of the
smaller air chamber(s)
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
7
Pontoon Boats:
Capacity:
Capacity for Pontoon Boat is found in ABYC Standard H-35 and in
Canada these are covered in TP1332.
http://www.tc.gc.ca/BoatingSafety/regs.htm
Section 4, Hull Design Requirements.
Sub Section 4.3 covers Capacity and flotation for multihull vessels,
that is, pontoon boats.
There does not appear to be a specific section of the RCD that
covers Pontoon boats.
There are two methods of obtaining the capacity of a pontoon boat.
The first is calculating the submerged displacement and the second
is by adding weights until the pontoons are fully submerged.
To obtain the displacement you need
Total length of the pontoon in feet
Length of the pontoon in inches
Pontoon radius in inches
Pontoon diameter in inches
Boat weight in lb
Engine weight in lb
Most pontoon boats have a nose cone and some have an end cap or cone
on the stern. Do not treat these as part of the length. Only use
the length of the pontoon between the nose cone and the end cap.
Calculate the volume of the nose cone and the end cap separately.
RadiusNose Cone
End Cap
Pontoon Length
The easiest way to determine the volume of the nose cone or end cap
is to fill them with water and measure the amount of water. Another
way is to put them in a tank and add weight until they sink. Either
way can give you the weight of the volume. Then divide the weight
by 62.4 lbs per cubic feet, to get cubic feet.
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
8
For two or three pontoon boats with an
outboard motor and round pontoons:
Volume of the pontoon equals:
The length (inches) x 3.142 X radius X radius. /1728 = vol. cu ft.
Or length cm X r (cm) x r (cm) / 1000 = cubic meters
Volume of the pontoon + volume of the cone + volume end cap. = Total
volume of the pontoon
Do this for each pontoon. If they are all the same size then just
multiply by the number of pontoons. If the boat has a third log
that is a different size then you will have to calculate the
displacement separately.
Add up the volume of the pontoons.
D = Displacement = Total volume of all pontoons X 62.4
Mwc = Maximum weight capacity
Mwc = Displacement – boat weight / Square root of pontoon diameter
in inches minus 2.35 for a two log pontoon
Mwc = Displacement – boat weight / Square root of pontoon diameter
in inches minus 1.35 for a three log pontoon
C = Persons Capacity = Maximum weight capacity – engine weight
Number of persons = persons capacity (weight)/141. = C/141
Example:
Number of pontoons: 2
Pontoon Length (less end cap or nose cone): 252 inches (6.4 m)
Total Pontoon Length: 25.2 feet (7.7 m)
Pontoon Radius: 12.5 inches (31.75 cm)
Pontoon Diameter: 25 inches (63.5 cm)
Nose cone volume 6.5 cu ft
Boat Weight: 2100 lb (952.5 kg)
Engine Weight: 655 lb (297.1 Kg)
(For outboards, use the combined weight in Table 1a Col. 10, in S-
30. For inboard or stern drive use manufacturers weight of engine
and sterndrive package.)
The pontoons on this boat have a nose cone but no end cap.
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
9
The length x 3.142 X radius X radius
/1728 = vol. cu ft
252 X 3.142 X 12.5 X 12.5 / 1728 = 71.6 Cu. Ft.
(640 cm X 3.142 x 31.75 cm x 31.75 cm /1,000,000 = 2.028 cu m)
Volume of the pontoon + volume of the cone + volume end cap. = Total
volume of the pontoon
71.6 + 6.5 + 0 = 78.1 Cu. Ft.
(2.028 + 0.18 + 0 = 2.212 cu m)
Volume of pontoons times 2
78.1 X 2 = 156.2 Cu. Ft. (4.424 cu m)
D = Displacement = 156.2 cu ft X 62.4 lb/cu ft=9746.3 lb(4420.8 kg)
Mwc = Maximum Weight Capacity
Displacement – Boat Weight/ Square root of pontoon diameter – 2.35
Mwc = 9746.3 – 2100 / 5 - 2.35 = 2885.4 lb. (1308.8 kg)
C = Persons Capacity = Maximum Weight Capacity – engine weight
C = 2885.4 – 655 = 2230.4 (1011.7 kg)
Persons = 2230.4 / 141 = 15.8
Determining Pontoon Capacity by Testing.
Maximum Weight Capacity
Add weight to the pontoon boat until all pontoons are awash over
their entire length.
Mwc = Maximum Weight Capacity =
Total Weight – Boat weight/Square root of pontoon diameter - 2.35
(1.35 for three log pontoon boats)
Persons Capacity By Test:
For transverse stability: Place weights for engine, battery and fuel
tank in the location of each item. Add weight on one side of the
pontoon boat evenly distributed fore and aft and as far outboard as
practicable, within one foot from the edge of the platform, until
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
10
the top of the platform on the loaded
side is awash. Repeat this on the other side. Record the weights
for both side.
For longitudinal stability: (fore and aft) Add weights on the
platform, with the center of gravity on the boats centerline. They
shall be placed 1/4 of the length of the deck from the forward end.
Add weight until the forward edge of the deck becomes awash. Repeat
this with the weights placed 1/4 of the length of the deck form the
aft end of the deck. Record the weights.
The smaller of the weights in the transverse stability test or the
longitudinal test shall be used to determine the Maximum Persons
Capacity. The maximum persons capacity is 90% of the weight.
Example
Transverse tests Port = 2500 lbs Starboard = 2550 lb (1020.6 kg)
Longitudinal tests Forward = 2600 lbs Aft = 2650 lb (1202 kg)
The lesser of the above is 2500 lbs. 90% of 2500 = 2250 (1020.6 kg)
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
11
Inflatable Boats
This includes both inflatable boats and rigid hull inflatable boats
(RHIB).
The ABYC standard for Inflatable boats is found in H-28.
Canada has specific standards for capacity of inflatable boats found
in section 4.4 of TP1332
The weight and persons capacity in the following is from the
Canadian standard because it is easier to follow. However, the
results are the same as those determined using the ABYC standard.
Where a power-driven small vessel is of inflatable or rigid
inflatable construction, that is not over 6 m (19 ft 8 in)
in length, the recommended maximum load in kilograms shall
be determined in relation to the total volume of inflatable
tubes (V) and the dry weight of the vessel as follows:
GL = (V X b X 0.75) – W
Where
GL = gross load in kilograms
Vt = the total volume of the inflated tubes in cubic meters,
and where appropriate, the volume of the rigid or inflated
hull below the cockpit sole.
Some inflatable boats have an inflatable chamber in the
floor and this should be included when calculating the
maximum capacities. However I will not include a floor
chamber in the examples and questions.
b = constant buoyancy factor = 1000 kg/m3 (62.4 lb/cu ft)
W = dry weight of the vessel in kilograms
The following variances, dependent on design features, are
applied to the recommended maximum load results calculated
by 4.4.2.1. Load reduction for the minimum number of
chambers in the collar is as follows:
(a) 1 air chamber = 50% load reduction;
(b) 2 air chambers = 33% load reduction;
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
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(c) 3 air chambers = 25% load reduction;
(d) 4 air chambers = No load reduction
C L
Chamber 1
Chamber 2
Chamber
3
Chamber 4Chamber 5
Chamber Volume = Length x radius X radius X pi = L X R X R X 3.1416
5 Chamber Inflatable
If you calculate the volume in inches divide the result by
1728 to get cubic feet.
ABYC defines inflatables by the following categories.
Type I inflatable boat – An inflatable boat capable of
taking a maximum outboard engine power of 4.5 kW (6
hp).
Type II inflatable boat – An inflatable boat with an engine
power rating of greater than 4.5 kW (6 hp) to 15 kW (20
hp).
Type III inflatable boat – An inflatable boat with an
engine power rating of greater than 15 kW (20 hp) to 75 kW
(99.9 hp).
Type IV inflatable boat – An inflatable boat with an engine
power rating of greater than 75 kW (99.9 hp).
Recommended Maximum Number of Persons
Where a power-driven small vessel is of inflatable or rigid
inflatable construction and is not over 6 m (19 ft 8 in) in
length, the recommended maximum number of persons shall be
determined in relation to gross load and engine weight in
kilograms as follows:
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
13
Where
GL = gross load in kilograms
We = engine weight in kilograms (for weight of an outboard
engine use the table in ABYC S-30, col. 3. In TP1332 Table
4-1 it is col. 2)
75 = assumed weight of one person in kilograms (165 lb)
From the ABYC Standard: Persons capacity: The persons capacity
(n) shall be determined by the manufacturer and calculated per H-
28.9.2.1. In no case shall it exceed the maximum load
capacity (m) divided by 75KG (165 pounds).
Do not use the formula Weight + 32 /141 for inflatable
boats.
ABYC Standard H-28 also includes a static stability test
which tests whether the vessel will capsize if a specified
amount of weight is placed on one side or the of the boat.
The test is to be conducted with the engine or equivalent
weight, but without fuel, fuel tank, or battery. The engine
weight shall be table 1a column 3 of S-30.
For ABYC Type 1 inflatable boats the test load in kilograms
is (0.67 X n X 75)
For Type II, III, and IV the test load is (n x 75)
n = maximum number of persons
The test weight is placed to one side of the boat, evenly
distributed along the side, over the inboard side of the
buoyancy chamber.
If the boat capsizes it fails, if not it passes.
Example:
Overall Length: 12.6 Ft (3.8 m)
Inside Length: 8.4 Ft (2.55 m)
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
14
overall width: 6 ft (1.83
m)
Inside Width: 3 ft (0.92 m)
Buoyancy Tube Diam. 1’ 6” (0.455 m)
passengers 6
maximum Weight Cap. 1653 lb (750 kg)
Boat weight 163 lb (74 kg)
Compartments 3
Hp (o/b) 25 hp (19 kw)
Engine weight 187 lb (85 kg)
The boat is given a stability test and the maximum weight
it could support was 450 kg.
Over all tube length = 2 x 3.8 m = 7.6 m (24.93 ft)
V = 7.6 m x 3.1416 x (.455/2)X(.455/2)=1.2358 cu m (43.6 cu
ft)
V = 1.2358 cu m X 1000 kg/cu m = 1235.8 kg (2724.9 lb)
GL = (1.2358 X 1000 X .75) – boat weight(does not include
engine weight)
GL = (1235.8 X .75) – 74 – 85 = 781.35 kg (1722.9 lb)
But Since this is a 3 chamber boat the load is reduced 25%.
GL = 781.35 x .75 = 586 kg (1292.12
Persons = GL – Engine Weight/75 = 586 – 85/75 = 6.68 (7)
However the maximum test weight was 450 kg (992.25 lb)
Persons = 450/75 = 6 persons. (992.25/165) = 6 persons
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
15
Questions:
1. Look at the below boat: is it a canoe using the ABYC
definition of what is a canoe?
Length 15' Beam 38 3/4" Weight 65 pounds Height at Stems 23" Depth 12
a. It is a canoe **** b. No it is not a canoe
Answer: a. The maximum allowable beam for a 15 foot canoe
is 1/4 of 15 feet which is 45 inches. I fits the definition
of a canoe because the maximum beam is less than 1/4 of the
length.
2. A boat is 17 feet long and is 39 inches maximum beam.
The boat has a transom and a mount for an engine. The
transom is 22 inches wide. Is this a canoe?
a. It is a canoe b. It is not a canoe ****
Answer: b. The maximum allowable beam for a 17 foot canoe
is 40 13/16 inches. The maximum allowable width of either
end is 45% of 40.8 which is 18 3/8 inches. The transom
exceeds 45% of the maximum beam of the boat. If the
transom were less than 18 3/8 inches then it would be
less than 45% of the maximum beam and fit the definition
of a canoe.
3. A canoe is made of polyethylene plastic and has the following
dimensions. For K use the value for ABS plastic. The Maximum Weight
Capacity is?
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
16
Length = 17 ft 2 in (5.2 m)
Width = 37 in (93.9 cm)
Weight = 80 lbs (36.2 kg)
Displacement = 3265 lb (1480.9 kg)
a. 1306 (592.4 kg)
b. 3185 (1444.7 kg)
c. 1270.4 (576.25 Kg) ***
4. The Maximum Persons Capacity based on Maximum weight capacity
could be.
a. 1302 lb (590.6 kg) or less
b. 1536 lb (696.7 kg) or less
c. 1270 lb (576 kg) or less ***
**** Solution: W = 0.40 (D – Wc) = 0.40 (3265 – 80) = 1270.4 (576.25
Kg)
For the next three questions use the following information:
Number of pontoons: 2
Pontoon Length: 18 feet
Pontoon diameter: 28 inches
Pontoon radius: 14 inches
Boat weight is 940 lb
The engine is a 45 hp outboard
The pontoons are circular.
There are 2 portable fuel tanks of 6 gallons each.
Each nose cone is 4.15 cubic feet.
5. What is the submerged displacement weight for this pontoon boat
a. 5491 lb **** b. 5941 lb c. 2746 lb d. 2647 lb
**** Solution: 18 ft x 12 = 216 inches
Vol = (216 x 3.1416 x 14 x 14)/1728 = 76.97 cu ft
Vol = (76.97 + 4.15) = 81.12 cu ft
D = 2(81.12 cu ft x 62.4 lbs cu ft) = 2(5061.83 lb)=10123.7
6. What is the Maximum Weight Capacity?
a. 2970
b. 2790
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
17
c. 2408 ****
e. 2480
***** Solution:
The Maximum weight capacity = Mwc
Mwc = Displacement – boat weight / Square root of pontoon diameter
minus 2.35 for a two log pontoon
Mwc = 5491 – 940 / sq root of 18 – 2.35 = 4551/1.89 = 2407.9 = 2408
Mwc = 10123.7 – 940/ sq rt 28 – 2.35 = 9183.7/(5.29-2.35) =
9183.7/2.94 = 3123.7
7. What is the persons Capacity?
a. 2408
b. 2703
c. 2730
e. 2307
***** Solution: Engine Weight from S-30 table 1a col 10 for a 45 HP
engine = 418 lb
C = Mwc – Engine weight = 2408 - 335 = 2073
3123.7-418 = 2705.7
8. How many persons is this.
a. 12
b. 14
c. 15 ****
d. 17
**** solution: 2073 /141= 14.7 (15) 2704/141 19.1
9. Given the following inflatable Boat
Overall length: 11 ft 6 in (3.5 m)
Inside Length: 7 ft 7 in (2.3 m)
Overall width: 5 ft 3 in (1.60 m)
Inside Width: 2 ft 6 in (0.762 m)
Buoyancy tube Diameter: 1 ft 5 in. (0.4318)
Boat weight 141 lb (64 kg)
Air Chambers 3
Maximum Rated Horsepower 25 (19 kw)
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
18
Engine Weight = 230 lb (119.5 kg)
Chamber 1 and 2 = 8 ft by 1 ft 5 inch diam.
Chamber 3 = 6 ft 1 in by 1 ft 5 inch diam.
End Caps = 0.5 Cu ft each.
C L
Chamber 1
Chamber Volume = Length x radius X radius X pi = L X R X R X 3.1416
Chamber 2
Chamber 3
3 Chamber Inflatable
NOT TO SCALE
8 ft x 1 ft 5 inch
8 ft x 1 ft 5 inch
Diameter
2 ft 6 in
Diameter 5 ft 3 in.
Vol = 9.59 Cu ft
Vol = 12.6 cu ft.
End Caps
Vol = 0.5 Cu ft
What is the maximum Weight Capacity?
*****Solution: 1133 lb (544.5 kg)
Anything with 2 or 3 pounds of this is Ok
GL = V x b X 0.75 - W
Chamber 1 Vol = 138 in x 17in/2 X 17/2 x 3.1416/1728 = 18.097
End Cap vol = 0.5 Cu ft
Total Vol one side = 18.097 cu ft + 0.5 cu ft = 18.597 cu ft
Total volume = 2 x 18.597 = 37.194
GL = (37.194 cu ft x 62.4 x 0.75) – (141) = 1599.6792 lb
For a 3 chamber boat reduce GL by 25%
GL = 1599.6792 x .75 = 1199.7594 lb
Chamber 1 = 3.5 m x .2159 x 0.2159 x 3.1416 cm = 0.512536
End Cap = 0.01416 cu m
Total Vol of on side = .51236 cu m + .0.01416 Cu m = .52652 cu m
Total Vol = 2 X .52652 = 1.05304
GL = (1.05304 cu m x 1000 kg/m sq x 0.75) – (64) = 726.0437kg
For a 3 chamber boat reduce GL by 25%
GL = 702.0201 X .75 = 544.5328 kg
10. What is the maximum number of persons?
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
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Solution:
544.5328 Kg – 119.5 / 75 = 5.667
For English units:
1199.7594 – 230 / 165 = 5.877 = 5.9
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
20
Appendix A.
TABLE I - HORSEPOWER FOR CANOES OR KAYAKS
Canoe Length
Maximum Horsepower Rating
Maximum Kilowatt Rating
Under 15 ft. (4.6m) 3 2.25
15 through 18 ft. (4.6 - 5.5m) 5 3.75
Over 18 ft. (over 5.5m) 7 5.25
TABLE II - WEIGHTS (POUNDS) OF OUTBOARD ENGINE/MOTOR AND
RELATED EQUIPMENT FOR VARIOUS BOAT POWER RATINGS-
HORSEPOWER (KILOWATTS)
Dry Weight-Engine/Motor
Swamped
Weight
Battery
Weight
Submerged
Weight
Engine/
Motor
Horsepower
Rating
kW
Engine/Motor
Portable
Fuel
Tank
Total
Engine/Motor
Engine/Motor
0-2.0† 0-
1.5
30 (13.75 kg) - 30 24 25† 21
2.1-3.9 1.6-
2.9
40 (18.2 kg) - 40 34 29
4.0-7.0 3.0-
5.25
70 (31.75 kg) 25 86 77 51
† and electric motors
Lesson 6 Canoes, Kayaks, Pontoon Boat and Inflatables
21
TABLE III - FACTORS FOR CONVERTING VARIOUS CANOE OR KAYAK
MATERIALS FROM DRY TO SUBMERGED WEIGHT
Material
Specific Gravity
Factor
Steel 7.85 0.88
Aluminum 2.73 0.63
Fiberglass 1.50 0.33
Kevlar 1.30 0.24
A.B.S. 1.12 0.11
Oak 0.63 -0.56
Mahogany 0.56 -0.78
Medium Density Polyethylene 0.96 -0.06
Ash 0.56 -0.78
Yellow Pine 0.55 -0.81
Fir Plywood 0.55 -0.81
Mahogany Plywood 0.54 -0.83
Royalex 0.50 -0.95
Cedar 0.33 -1.95
Balsa end grain 0.16 -5.24