WINTER ICE AND SNOW WIND SURFING SAIL POWERED ICEBOAT CONVERTIBLE TO WATER SAILING CATAMARAN

VOILIER POUR LA GLACE ET LA NEIGE SE TRANSFORMANT EN CATAMARAN SUR L'EAU

English Abstract

An iceboat includes a hull and a perpendicular extending beam attached to the
rear end of the hull.
A mast is mounted at or near the centre of gravity rearward of the occupant
pilot seat in the hull
and supports a wind surfing sail. Skate blade mountable V-hull skis are
attached to the front end
of the hull and to the outer ends of the side struts beams.
A catamamran includes two outer hulls mounted to a forward and a rearward
traversing beam on
which is built the deck area. It is rigged and operated as a conventional
sailboat and has the
capability of sutaining higher wind forces, therefore permitting the effect of
hiking one side of the
boat out of the water while permitting the retention of directional control.

Claims

CLAIMS
Dynamic balancing
Claim 1
In theory, there is a positive interaction between a forward pilot and a rear
sail arrangement. A
large low pressure area is created by the sail and this is what gives it lift.
This low pressure area
can also pull air from areas above and below the sail resulting in lateral air
flow. This only
damages the sail lift. However, in the present design, the pilot in front of
the sail creates a low
pressure area behind the pilot which acts to shut off air flow from the bottom
of the sail (same
effect as closing the gap). Also, the sail area behind the pilot probably
isn't generating much lift
but it does have an effect on reducing the pilot drag - and possibly a
significant effect. You can
also see this on many subsonic craft where the nose is relatively blunt but
the trailing edge is very
streamlined. Also, a low rigged sail may generate slightly less power but
seems to have a
significant effect on both pilot and sail drag resulting in an improved
overall lift to drag ratio.
Claim 2
There is a trade-off on where to place the boat's centre of gravity (cg).
Having the (cg) forward
helps the manoeuvrability and high wind safety, keeping it back results in
better leverage to keep
the boat from hiking in lighter winds where the mast downward pressure isn't
as significant.
Stable turning is achieved because the cg is place 1/3 from the boat rear (2/3
from the front)
which results in equal weight on all three runners. This gives maximum
possible runner weight
while insuring stable steering under all conditions.
Claim 3
The sail mast downward pressure location (where the mast attaches to the
fuselage) is placed as
close to the boats cg as possible the reason for this is that the mast can
exert a huge downward
force on the fuselage and being a force just like the pilots weight, it can
shift the boat's centre of
gravity towards the masts down force location. By placing the mast down force
near the boat's cg,
the "dynamic" cg of the rear sail boat shifts very little during sailing. This
is the main reason that
"spinout" or "flicker" is nearly eliminated in this configuration. One of the
most fun manoeuvres is
a high speed down wind turn in windy conditions. But this can also create the
highest mast
downward pressure. Since the mast down pressure is nearly over the static cg,
the balancing
between the sail centre of effort (ce) and the boat's cg remains nearly stable
and fixed. And, since
the mast down pressure is behind the boat cg, the stable steering condition of
more pressure on
the rear runners is also maintained. A big shift in boat cg and front runner
loading during windy
conditions is what causes spinout and both of these effects are almost
eliminated in the rear sail
design.
Claim 4
Finally, the sail ce is placed relative to the boat's cg. This is important
for both performance and
safety. The boat cg is important as this is where a force applied to the boat
will cause it to slide
exactly sideways. Apply the force in front of the cg and the front of the boat
slides, apply the
force behind the cg and the rear of the boat slides. For safety, you always
want to apply the sail
force behind the boat's cg as you can control a boat with the rear sliding but
its much more
difficult (and dangerous) with the front sliding. A rear sail boat inherently
has the sail ce behind
the boat cg so will be safe. - i.e., the rear end will always get blown down
wind but you can still
steer the boat. However, for performance, you want the sail ce to be
relatively close to the boats
cg (but still behind). This is of course done by raking the rear sail forward.
(see drawing no.4)



Claim 5
Forward raked foils can be powerful but unstable on aircraft. However, in this
case they are stable
and the reason is that the entire sail area is behind the sails rotational
axis. Also, normally the pilot
will be leaning slightly to the windward side of the boat in order to gain
maximum leverage from
his or her weight. This puts the pilot out of the way of the forward raked
mast.
Claim 6
Hiking occurs when the up wind runner lifts because of torque on the boat.
Weight over the rear
axle or beam makes the boat less susceptible to hiking and also lets you get
more power out of the
sail. In light winds. there is less weight on the rear beam than on a front
sail configuration and this
makes the boat more prone to hiking in light wind. However, as the mast
downward force
increases due to higher winds, the pressure on the rear axle can become
greater for the "rear sail"
yacht. It would seem that the stability of the rear sail yacht almost
increases in higher winds. The
geometry of the rear sail, forward pilot boat requires a significantly higher
drag lifting force on
the sail to lift the front end.
Claim 7
A near but behind cg positioned mast produces a boat with good performance in
light wind but
that is exceptionally controllable in higher winds provides much greater front
of mast upright
seating comfort for the pilot. Also there is virtually nothing blocking a fill
front view making it
also easy to look to the rear before initiating a tack or jibe. It is also
very easy to see the pilot
making hand signalling before turning. The contoured seat belted seat and the
adjustable foot
pedals (12 inches in 3 inch steps) allows for a very comfortable stance.
Claim 8
The main goal of this unique mast position balancing is to place the sail
nearest the centre of
gravity with a small amount of "weather helm" for safety. This is achieved on
this boat by raking
the sail forward. However, the extremely interesting thing is that the mast
downward pressure is
nearly over the boats static centre of gravity resulting in the boats
balancing being stable even
under wild sailing conditions. The front pilot weight not only results in a
nimble boat but also in
combination with the rear sail, keeps the front end on the ice and in control
in the bigger winds. It
would also be desirable to provide a forward raked rear mast iceboat in which
the mast position
provides a weight distribution which makes it easier to turn the iceboat than
in "standard design"
iceboats. With the rear mounted sail and the geometry of the boat, there is
nearly equal weight on
each runner. This creates higher proportional weight on the front runner with
exceptional turning
results.
Claim 9
The present design includes a system to permit the ea:,y adjustment or
dismount and change of
the wind surfing type mast, boom and sail size combinations in order to take
advantage of current
wind conditions in effect and to reduce excessive hiking, although a certain
amount of hiking is a
desirable characteristic sought by many ice boaters. The basic design of the
iceboat makes it
practically impossible to tip over and in such an event, safety features such
as secured mast
rigidity are built in to prevent injury to the seat belted motorcycle helmet
wearing pilot. Because
the sail sits behind the pilot, weight distribution is equal on all three
runners producing handling
characteristics car designers would envy.

Description

CA 02326458 2000-12-O1
~~ DESCRIPTION
Construction details
The present invention is a lightweight snow and ice sailing boat convertible
to a summer use
catamaran making use of a hull mounted automatic self leveling hydrofoil anti-
cavitation planar
wing system. The ice boat's body, side strut and ski and skate assemblies'
stiffness are derived
from the use of MIG welded, lightweight, rust resistant aluminised and
stainless steel metal alloys
of round and square tubing. A square tubing central member is continued
throughout the fuselage
to form the main load bearing system.
The iceboat is built with a rust resistant, painted, metal hull (1) and mast
assemblies (2) having a
rearward ofupright seated pilot, near centre of gravity wind surfing sail (3)
and supporting single
mast and boom assembly, which provides unique advmtages over previously
devised control
systems. It makes advantageous use of a mast mounting system which permits the
quick and easy
changing of wind surfing sail and mast configurations. It permits the easy
removal of the V-hull
snow runners assembly (4) and the removal of blade runners (5) for maintenance
purposes or for
changing the system (6) to summer use by replacing the winter runner assembly
with summer
catamaran hull assemblies.
The present ice boat includes a hull having forward (7) and rearward (8) ends,
and a two section
removable beam (9) attached to the rear end of the hull and having first and
second pin locked
( 10) dismountable opposed ends extending outwardly from the opposite sides of
the hull. A
plurality of dismountable combination skates and V-hull ski assemblies are
attached to the hull
with one skate assembly attached to the front end of the hull and one skate
assembly attached to
._.. each of the first and second ends of the side strut beans.
Rear beam canted runners
To prevent adverse effects of rear runner side slip deflection as they angle
"out" from wind loading
forces on the sail, an outward blade angle of 5 degrees is built in. (11)
Adjustable steering rudder foot pedals
Rudder pedals ( 12) connected to push tubes ( 13) control the steering of the
front runner. A toe
push on the right pedal initiates a right turn and a toe push on the left
pedal initiates a left turn.
The pedal system can be adjusted by nearly 8 inches in 4 steps ( 14) meaning
all users can find the
perfect setting. For additional safety, the steering linkage is dual redundant
with two push rods
either of which can be used to steer the boat in an emergency. It is possible
to "heel" a pedal to
initiate an opposite direction turn. Convenience is a big factor in making the
ice boating
experience enjoyable. Convenience not only means simple set up and take down
but also means
easy car topping and storage. The steering assembly is a simple robust design
that can be easily
separated from the fuselage. this not only makes the fuselage weigh less. it
also takes a lot of the
awkwardness out of getting the fuselage on the roof racks or in
transportation.
Mast and boom assembly
The mast and boom assembly are made of aluminilum tubing type 6061 T-6 or of
commercially available carbon composites. All other related hardware materials
such as pulleys,
ropes, rope guides mast mounting system, seat, seat belt should make use
of/and/or polymers,
carbon, stainless steel, aluminium, rubber, copper and nylon.


CA 02326458 2000-12-O1
''~' Mast base assembly (15)
This assembly interfaces the wind surfing sail mast base with the boat. It
uses a standard Chinook
type cup. The bottom bracket attaches with six stainless steel screws and
allows the sail to be
easily put on and taken offthe boat and also allows the sail to rotate out the
back of the boat to
prevent damage during setup.
Mast stay brace and bracket system (16)
Wind surfing sails are designed to be supported at the base ofthe mast and at
the boom. The
present design mast stay brace bracket systems made from polyurethane with a
carbon fiber insert
perfectly accomplishes this allowing the sail and mast to twist off as the
sail designers intended.
This system allows the mast to rotate with the sail and also distributes the
mast downward force
between the mast and the brace. The mast brace interf ices with the mast in an
area where the
mast is reinforced fiuther increasing reliability. The cables and adjusters (
17) are all quick release
and constructed of stainless steel. A camlock buckle ans strap hold the mast
in place Also a
aluminium mast helper bar ( 18) using a load bearing washer assembly make use
of a solid PVC
insert guide shaft to interface the mast bracket and the downhaul sail base
cleat.
Bilateral sail sheeting system
Sheeting a wind surf sail with the high fixed boom end presents an interesting
problem. The
bilateral sail sheeting system allows high performance Sheeting of wind
surfing sail without
modifying them. This system is designed to put sheet forces on the sail in the
same manner as the
sails were designed for. Bilateral sheeting also allows the sail to be filly
sheeted to centre which is
important when very high apparent wind angles are achieved. The present design
incorporates a
novel sheeting system ( 19) which sheets the sail form the ends of the ice
boat rear beam rather
than from a point in the centre of the boat (20). This sheeting system allows
the sail to be sheeted
very close to the centre which is important at high speeds where the apparent
wind is more
straight on. Once the sail is fiilly centre, the sheet begins to flatten the
sail which in effect "kicks it
into overdrive". To the boat pilot, the sheet works exactly like a sail boat
sheet. Pull on the single
sheet rope handle to go faster, let offto slow down. A ratcheted car hand
brake system with a
mechanical push button release system can also be installed in order to permit
the setting of ideal
constant sheet pull. (21 )
Ski assemblies
The ski assemblies (4) are constructed of either painted steel or stainless
steel alloys. A UV
inhibitor provides the outer protective coat. The removable skate blades are
made of wear
resistant stainless steel or of painted or teflon coated metal bottoms with
other surfaces painted to
prevent corrosion damage. An enclosed rocker system (22) is incorporated at
the end ofthe rear
beam struts and is mounted at the front steering ski assembly through a
vertical bushing fixed (25)
through the central beam . This rocker assembly system also provides ski
flexibility in order to
follow terrain contour. An additional shock absorber (23) ski and frame link
is installed behind
the front steering system and at the side beam struts to provide a double
joint system (26)
providing more hull flexibility and therefore the smoothest possible ride. A
spring (24) tensionner
is added to the front mast stay brace cable to permit some degree of mast
flexibility and for the
pilot to apply extra forward raking by hand pulling in order to achieve faster
speed.
2


CA 02326458 2000-12-O1
' SPECIFICATION
Background of the Invention
1. Field of the invention
The present invention relates, in general, to sailboats and, more
specifically, to iceboats.
2. Description of the Art
Iceboats have proven to be a popular type of roiling craft in colder climates.
An iceboat
typically includes a small, elongated hull, a beam connected to the rear end
of the hull and
extending outward from the hull, and three runners of skates, one mounted on a
springboard
extending forward of the front end of the hull and one on each outer end of
the plank. A sail is
mounted on a mast and a boom attached to the mast in much the same manner as
on a sailboat.
the mast is locate in front of the forward end of the cockpit in the hull.
However, the forward mounted mast places the sail in a location generally in
front of and
to the side of the occupant in the cockpit which has a tendency to block the
view to one side of
the iceboat. This could result in a dangerous situation, particularly due to
high speeds of iceboats
as compared to much slower sailboats in water.
i


CA 02326458 2000-12-O1
TECHNICAL DETAILS
Specifications
Configuration: Tri-rail, front steered, sit down, rear mount wind surf sail
Length: 12 feet
Width: 8 feet
Weight: 150 pounds including steel runners but without sail rig
Clearance ski base: 4 inches above the snow. Blade base : 6 inches above the
ice
Steering: Direct linkage push rod, adjustable by 12 inches (4 steps) for pilot
height
Runners: V-hull skis 36" in lenght by two angled faces of 6"each in width with
30" runner blades.
Strut/runner linkage: in house rocker design with optional strut/rocker
mounted shock asbsorber
Sheeting: Bilateral with single sheet control rope
Hardware: Harken, Race Lite
Body, front and rear beams: Aluminised, stainless steel alloys, painted steel,
IJV final coat
Max. capacity: One rider, 300 pounds
Mast base compatibility: in house articulated mast height adjustable base cup
Adjustable boom outbaul
The boom has 1 inch adjustment increments with the nominal 10% draft position
shown as boom
position "0". For light winds, optimum performance is achieved by shortening
the boom to the
.,...._ "-1'" position which results in a fiiller sail. On the other hand, if
the wind picks up, higher speed
and pointing ability may be achieved by lengthening thv boom to the "+ 1"
position . On large
sails it may be preferable to experiment with shortenin; the boom to the "-2"
position in very light
winds. Outhaul adjustments done with the sailing rig mounted on the ice boat.
the outhaul is not
adjustable while sailing but its an easy adjustment that can be done at any
time with the boat
stopped.
Adjustable sail outhaul
On the fly performance is increase with an adjustable outhaul built in to the
boom's rear end. A
"suspension rope" is installed about 5 to 6 inches from the boom's end. On
both sides of the
location 5/16" holes are drilled and copper tubing is inserted and the ends
are flanged to reduce
the rope wear and abrasion. The suspension rope goes through the "eye" of the
sail rear and keeps
the boom end from excessively drooping when the outhaul is let way out. The
suspension rope
should be loose enough to allow the outhaul to travel on the order of 4
inches.
The outhaul adjuster rope is run through the "eye" of the sail, through a
block attached to
the rear of the boom (Harken 224 Micro Block) for a '?:1 leverage, then up
towards the front of
the boom At the maximum width of the boom, a custom "eye" routes the rope to
follow the
contour of the boom. The rope goes to another block (Harken 224) attached to
the front of the
boom and then is routed down to a cleat attached to the mast helper tube. From
this position, the
pilot can easily reach up and grab the sheet adjuster while sailing to best
trim the outhaul or the
rope can be linked to a ratcheted push button release car hand brake to adjust
best outhaul trim. A
four to one pulley advantage can also make adjustment easier.


CA 02326458 2000-12-O1
Finally, addtional descriptions, specifications and techtucal drawings are to
be submitted shortly.
More information will be added through specific parts detailed drawings and
with further
information on hydrofoil catamaran. The easy removal without tools of the
Winter use ski and
blade system will be described as well as the method for replacing said system
with Summer use
hydrofoil catamaran hulls and rudder system. The hydrofoil system will permit
speeds equivalent
to the winter use ski system.

Representative Drawing