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simba_the_sailor
27 Jan 2015, 09:27 AM
Bladerider X8 – Sailing Help Notes
Last Update - 25 February 2007
© Bladerider International Pty Ltd
IMPORTANT SAFETY WARNINGS!!!
• It is recommended that beginners wrap padding material like foam or large
rubber hose around the side stay adjusters on the forward wing beam. This is
to protect the skipper in case of crash landing on the water.
• Do not use battened hiking pants, as the point loading on the carbon wing
frame will cause it to crack.
• Wear a long leg wetsuit to avoid scratches, brusies and cuts from sharp
objects such as the side stay adjusters and the foils.
• Do wear a lifejacket at all times.
• If you are sailing by yourself, always let someone know that you where and
how long you will be sailing.
• Sail at slow speeds in displacement mode when unsure of any hazards under
the surface.
• Avoid any direct pressure on the side of the hull, such as standing on the side
of the hull during a capsize recovery, as this may crush the foam underneath
the carbon fibre. It is recommended to stand on the chines of the hull if more
leverage is required.
3.1 Definitions
3.1.1 Wand
The tapered fiberglass rod hanging off the bow of the boat, that is connected to
levers and pushrods along the deck and down to the centerboard to flap on the
back edge of the main foil. The wand is held down to the water’s surface to
‘feel’ the how high the boat is above the water and to adjust the main foil flap in
order to maintain the altitude of the boat at a constant ride height of around 30-
60cms.
3.1.2 May Stick
The forward extension of the wand that 3-4mm elastic is attached to and kept
tight in order to pull the wand onto the water’s surface.
3.1.3 Ventilate
When a lifting foil breaks the surface, the foil is said to “Ventilate”.
3.1.4 Launch
“Launching” is the result of either the boat hitting the back or front slope of a
steep wave, and the wand is pushed back to induce sudden lift on the main foil,
causing the bow to rise up quickly into the air.
3.1.5 Bunny Hop
After the boat has launched, the usual result is that the main foil will ventilate,
but as the rudder foil is still lifting underwater, the bow is pushed down under
the water quite hard, as the boat is now pivoting in the air around the
centerboard. As a result of this “Bunny Hop”, the hull may completely submerge
underwater, but if the boat is kept flat, the volume of the hull, will allow it come
back to the surface.
3.2 Essential Prior Experience
It is not necessary to have mastered a Moth sailing before sailing a Bladerider.
Experience in sailing other high performance dinghies is adequate. However, as we have seen
before from big boat sailors, even that is not essential.
Basically, you need to be a good sailor, have a good understanding of apparent wind,
good balance, good fitness, reasonable strength. Leg strength and abdominal muscle strength is
a benefit for hiking the boat to windward. The mainsheet needs constant trimming, so good
shoulder strength is also important. The basic upwind technique is to pull the boat over the top
of you and hike comfortably with slightly bent legs. Hiking with straight legs is ideal, as this
allows you to get more leverage out over the water. But it is not necessary to be super strong or
super fit like other high performance dinghies.
The tiller extension grip is quite important. Unlike the 470, Laser or any trapezing boat,
the tiller should be held across the body, so that you thumb is towards your chest. This allows a
slower tiller movement at high speed and allows for the skipper to easily rotate the tiller
extension around to trim the rudder foil.
3.3 Sailing Environment for Learning
A relatively steady wind of about 10 knots and no waves is the ideal. Wind which is gusty
and shifty makes it more difficult for a beginner.
Avoid significant waves. Waves up to maybe 30 cms may be OK because you can clear
that chop when foiling. Bigger waves are difficult for beginners because they will not have
developed quick enough control technique to steer around the troughs as they learn to handle
the boat.
To sail the boat, you need 1.5m depth of water as a minimum, ideally with no sand bars,
reefs and no weed obstructing you. You can get around weed but it is better not to have it. Fish
and other marine life also debris in the water can cause problem. If you hit a large jelly fish at
high speed it may catapult you off the boat or worse still some foil damage, so that is something
to avoid if possible. If you do hit a submerged object in the water, as the boat is so light, it will
just flip over itself. But it is critical that you let go of the boat and tiller extension if this should
happen to relieve the boat of the momentum from your body weight which may damage it if you
hang on. If you are off the boat, the only impact is the boat onto the water and its mass is so
small that that it is unlikely that you will cause and damage.
3.4 Moving to the Water
It is extremely difficult to launch a foil Moth in onshore winds if there are breaking waves
or surf. If the waves exceed 300mm there is a danger of capsize and a broken mast or foils
snapping. We do not recommend this for anyone regardless of their experience. Therefore
launching in offshore winds is by far the easiest, however there are two options:
3.4.1 If a ramp is short, steep, difficult we recommend tip the boat over on land, take
the trolley off, fit and secure the foils to the hull so it is ready to sail. Then either
one person or two can pick up the hull, carry it to and drop it in the water and
go. If a third person carries the masthead so it does not drag, that helps. This
is appropriate for Lake Garda where the water becomes deep very quickly and
there are queues waiting.
3.4.2 The other option is appropriate for a more shelving bottom. We secure the foils
on the trampolines (under the toe straps); and two people lift the boat out of the
trolley and carry the boat upright by the wing frame into shallow water. The
sailor then pushes the boat out to chest depth; about 1.3 to 1.5m, tips the boat
over, fits the foils from the underside and pins them from the top. You cannot
see the deck when inserting the centerboard from the bottom so we use marks
on the centerboard which indicate the depth to which it should be inserted to
accept the pin so we can pin it ‘blind’. The sailor then connects the wand
mechanism to the centerboard and secures the rudder foil in place. When ready,
the skipper can right the boat by pulling down on the windward wing frame or
standing on the centerboard (close to the hull).
As the Bladerider has a dagger blade arrangement; you can lift the rudder and
centerboard higher for shallow water; when you get to deeper water you can push it down and
secure it with the retainer pins.
3.5 Moving Offshore
Once you have your foils secured into the hull, there are two ways to right the boat from
the on-its-side position.
3.5.1 If you are standing on the bottom you can jump on the centerboard close to hull
and right it like a normal boat. You can stand on the chine if necessary, but do
not stand on the side of the hull, otherwise you may crush the foam under the
carbon skin. As the comes up to 45 degrees, throw one leg over the wing bar
can get your feet in the middle of the boat as soon as possible. Pick up the
mainsheet and tiller and quickly bear away to get speed and balance.
3.5.2 The other method is to stand on the centerboard again and pull the windward
wing bar down into the water with you. Reach into the boat and grasp the
mainsheet and the tiller extension with your lower body sill in the water and legs
pointing away from the boat. Immediately bear away to sail off on a reach,
whilst swinging your body into the middle of the boat to get balance and the
wing frame out of the water.
If there is more than 8 knots of wind, the second method is the easier and faster way to
get in and go.
3.6 Approaching the Shore
Judging depth is always difficult, so the technique is to drop speed to around 1-2 knots
when unsure. Sandy beaches are the best. Concrete or rocks is the worst as they can damage
the foils if you hit the bottom.
When approaching the shallow water, remove the ball and socket joint from the bell
crank and both retainer pins from the foils. Be sure to go as slow as possible when doing so,
otherwise your foils will shoot up into the boat. You can then lift the foils up into the boat, just
enough though so that you still have steering and balance.
When in shallow water, put either leeward or windward wing bar in the water and inch in
very slowly until you think the water is shallow enough for you to stand up but the foils have not
yet touched the bottom. Immediately tip it onto its side to remove the main foil from the bottom
of the hull. The foil should float, so if necessary you can leave it in the water (except in an
offshore wind). Do not remove the rudder, but instead, lift it to its highest in its box and leave it
there until the boat is ashore and in its trolley. However ensure that it has elastic around the
blade to hold it in place and does not slip down.
3.7 Returning ashore
The normal technique is to right the boat by pulling down on the wing frame, put the
foils into the trampolines and secure them temporarily in the wing cover lacing and underneath
the toe straps. Don’t forget to lift the wand up as soon as possible and tuck it up above the lower
wing frame tube. and two people carry the boat ashore.
If there are two people to carry the boat to the trolley, that is easiest. If not the boat can
be left on its side in 100 to 200mm of water, you get your own trolley, fit the trolley to the boat
while it is on its side in the water, then right it by pulling down on the wing frame and wheel it
ashore by yourself.
3.8 Height Control
Height control is a new responsibility in dinghy sailing. It is shared between sailor and
wand. The wand is attached to the bow and senses the height of the bow above the water. The
mechanism between the wand and the flap on the main lifting foil gives fine control of the boat’s
height. When the boat is too low the wand will be pressed up and the mechanism will put the
flap down and this will bring the boat up.
When the boat is too high the wand comes forward and raises the flap and the boat
comes down. This gives very effective fine control of height. But the wand and its mechanism
must not be too sensitive else the boat would leap up and down as it tried to follow the crest and
trough of every wave. The art of the recent equipment development has been to create a
sensing mechanism which will give smooth accurate control at the desired average altitude
without responding to the crest and trough of every wave.
A second foil attached to the bottom of the rudder blade can also be adjusted by twisting
the tiller extension. The function of this movement is to provide a manual attitude and pitch
control.
The practical result is that this type of wand mechanism works very well indeed
PROVIDED the sailor sets the attitude of the foil - i.e. his hull - at the approximate angle of
attack required for the present and expected speed. At low speed the wand alone will not lift the
boat to start flying unless and until the sailor lifts the bow to give the required greater angle of
attack to the main foil. The sailor controls the altitude initially by moving his body weight fore
and aft; and uses the rudder foil for fine adjustment.
Once the boat starts flying it will accelerate quickly. The wand alone cannot stop it
climbing too high and launching unless the sailor lowers the bow to about the smaller angle.
needed at the expected higher speed. Again, the skipper does this primarily by moving body
weight forward, and will use the rudder foil adjustment for finer control of altitude.
The end result is that sailing the Bladerider calls for the synchronised coordination of
steering, sail trimming, and balance needed to sail a fast skiff, plus proactive control of altitude
primarily by movement of body weight and supplemented by rudder foil adjustments to enable
the wand to do its job of fine control of the flying height.
3.9 Sailing and Flying
There are two modes to sail the Bladerider:
3.9.1 Displacement Sailing
In the displacement mode the Bladerider is simply another sailboat, and will sail
upwind, crosswind and downwind in the normal manner.
3.9.2 Flying
To start foiling it is necessary to reach at 8 to 9 knots of boat speed and the boat
will simply just lift out of the water. It is hard to start foiling if you are sailing
either upwind or downwind. The most efficient technique is to reach to start
foiling, accelerate crosswind to build apparent wind, then turn upwind or
downwind with speed.
When beginning the main thing is to get into a reaching position, with body weight
positioned in the middle of the wing frame. Newer model boats do not require much or any
effort from the rudder foil control to lift the boat out of the water. The main foil plus the wand
configuration should be enough to lift the boat out on a reach.
Take off speed is about 9 knots boat speed. That will generate enough apparent wind,
even in as little as 6 knots of true wind to get the boat clear of the water and the skipper hiking.
The boat must be sailed flat or heeled to windward. If it is heeled to leeward the foils will push
the boat over and the boat will tip over by itself regardless of the skipper’s efforts to balance it.
Once it is clear of the water the boat will go completely silent; no noise at all, and will
accelerate immediately to a minimum of 11 knots depending on the wind. This is new art which
differs from normal sailing in two key respects:
The first is that to control these boats you need to think control in four dimensions -
pitch, altitude, heading and heel. The pitch of the boat controls the angle of attack on the foils,
and hence the drag induced on the foils. However it also has an effect on the lee or weather
helm on the boat, as the centre of effort can be easily moved fore and aft around the center of
lateral resistance on the foils.
The second is that the dynamics of these boats - their light weight and high speed -
require that height control be proactive rather than reactive. You have to be in charge and the
boat has to do what you want it to do. It is important to be proactive and not reactive. If you
try to sail by reacting to the boat, you will be too late - it has already happened. The human
response is not quick enough. Unless it is firmly controlled the boat will just do what it wants to
do.
For example, if the boat is clear of the water and the bow is up it will keep lifting. If you
do not correct and put the bow down before it is too late it will just launch and turn either way.
You have already lost control. The appropriate control is for the skipper to move his weigh
forward and/or to pitch the bow down to flatten the boat before it lifts too high. You have to
anticipate and act first. There is not enough time if you are traveling at 15 to 18 knots for any
corrections to be made once the boat is sailing too high.
This was demonstrated during a test sailing day in strong, unsteady wind and small
waves, some very good sailors were sailing the Bladerider for the first time. As a group, they
initially sat too far aft. The wand was doing all it could but the boat’s attitude was too nose-high
and it just climbed out and launched and they lost control. When they were encouraged to move
forward as the boat started to fly, the bow came down, the wand could then look after the
altitude, and they were then in control and able to begin to get the feel of this new craft.
Another important point to note is that because of the stronger apparent wind that the
Bladerider has once airborne, the sail needs to flattened as soon as possible with the use of
downhaul and vang. By using moderate to strong tension on the vang and downhaul at all times
when foiling, you will find the boat a lot easier to control and the boat will sail faster.
3.10 Landing
If the beginner wants to progress their skills with a series of short flights, then the
technique to bring the boat back down to the water is to stall the sail. This reduces drive force,
adds drag, slows the boat without upsetting the balance and the boat will settle back to the
water under control. Whether you are reaching or sailing upwind or down if you sheet in really
hard this will stall the main and push the boat down.
If you move forward or pitch the bow down with the rudder flap this will initially reduce
drag and accelerate the boat. If you do it to extreme, it will bring the boat down but much more
slowly. Another way if you must stop quickly is to heel aggressively and put the wing frame in
the water. This will kill the speed very fast, but it may drag the boat around in a direction you do
not want it to.
Therefore, the efficient, fast and controlled way to land is to stall the sail to reduce drive
force and increase drag and this will stop it flying.
3.11 Flying Faster
To make the boat sail faster use the tiller extension twist to control the rudder foil to
pitch the bow down. This will reduce the angle of attack of the main foil to reduce the drag, and
hence speed will increase. Alternatively the helmsman can move his body weight forward; as
this will have the same effect. Flattening the sail by more downhaul and/or vang will also reduce
drag and increase speed. As the apparent wind increases and goes forward, it will be necessary
to sheet in more closely.
The hard-leech fully battened sail acts like a solid wing and always has power. It is
important to keep a windward heel 5-10 degrees for maximum speed and lift from the rig and
foils. If it is allowed to heel to leeward at all, the foils will push the boat over to leeward, and will
result in the leeward wing bar hitting the water, making for a fast capsize.
Because the Bladerider sails so fast with respect to the true wind speed, particularly in
lighter winds, the apparent wind is from well ahead of the beam on all points of sailing. As a
result there is surprisingly little difference in sail settings between sailing close hauled, reaching
and tacking downwind.
3.12 Flying Upwind in Different Conditions
3.12.1 Light Wind and Flat Water
Light airs are difficult in that you need 5 to 6 knots to get it up on foils.
Displacement sailing is unstable - not as unstable as the skiff version but less
stable than when foiling. You need good balance to move around the boat to
keep it upright, and then a lot of skill to get it up in light airs. Generally this will
involve a few quick pumps on the mainsheet, body weight toward the back,
mast upright and lifting the bow with the rudder foil. But if you have around 7
knots of wind you should be able to foil straight away. In lighter winds you just
give it a go and see how it feels. Reach to start flying and accelerate; only then
turn upwind and heel to windward.
3.12.2 Moderate Wind and Flat Water
To sail upwind needs slightly more windward heel and hard sheeting of the sail.
3.12.3 Strong Wind and Flat Water.
Depending on the skippers body weight, in +15 knots set a really flat sail, tight
leech and exercise firm control. Strong winds are for experienced sailors, not
beginners.
3.12.4 Light Wind and Waves
This requires a tremendous amount of skill, but it may help to try and bounce
the boat off the top of a wave to help with initial flight and acceleration. Once
foiling, keep the rig fairly upright in order to stop the wing bars from hitting the
water and slowing the boat down.
3.12.5 Moderate Wind and Waves
The rig should be fairly upright once again but with a slight heel to windward if
possible, so the wings and skipper can clear the water when hiking.
3.12.6 Strong Wind and Waves
These conditions do not present a problem as most beginners fear. The boat
should almost float in between the troughs of waves and then just skim the top
of the wave’s crest. By contouring more along the waves the hull stays clear of
the water and the boat can move freely and fast. It really is a lot easier than
expected.
3.13 Flying Downwind in Different Conditions
3.13.1 Light Wind and Flat Water
The idea here is to look for pressure and sail as low as possible. Speed is good
but if you are heading in the wrong direction your VMG may be very low. Sail
settings are very important here. You need only moderate tension on the vang,
outhaul and downhaul. The fuller the sail, the better!
3.13.2 Moderate Wind and Flat Water
As in lighter winds, but as the apparent wind increases, flatten the sail to reduce
drag.
3.13.3 Strong Wind and Flat Water
As above, but it is possible to sail extremely low, so when jibing you need to sail
up high after the gybe to get the apparent wind around quickly. A lightweight
skipper may not need to let any control lines off downwind as they may be fully
powered up already.
3.13.4 Lighter Wind and Waves
This is certainly rare but difficult conditions. The decision must be made by the
skipper to sit on the wing bar and sail higher and faster across the waves,
otherwise sit in the boat to sail in displacement mode to go low and slow. A
VMG GPS will help determine the best angle to sail on.
3.13.5 Moderate Wind and Waves
Depending on the direction of the waves, it is sometimes easier to sit
comfortably on the wing covers to sail low but still foiling at around 10-12 knots
of boat speed. This may require the skipper to use aggressive fore and aft body
movements to stop the bow from pitching too high or digging into the back of a
wave. Aggressive rudder angle and trim may also be required to assist the boat
in not launching off the back of a steep wave. The alternative to sailing low and
slow is to sit on the wing bar and go for speed across the waves. It is important
to look for highest water as so the foils do not ventilate. If the boat looks like it
might launch up into the air off the back of a wave, the skipper can sheet in,
heal to leeward and bear away sharply to reduce lift and power. The boat should
slowly come back down to the water across the face of the wave.
3.13.6 Strong Wind and Waves
It is very important for beginners to not to try to fly the boat too much. Good
technique is to stall the sail and heel the boat to leeward if out of control or
overpowered. If there is any sudden acceleration of the boat it will be hard to
control and the boat will just launch off a wave and you will lose control. So try
to sail the boat a slower than normal downwind to be safe. Sometimes small
areas of flat water offer a chance to speed up a bit, but not for too long. You
can try and fly across these flat areas, then stall the sail to bring the boat back
down on the water before approaching any big waves. Whenever you feel that
the boat is trying to come out of the water too high, immediately bring it down
straight away. This way you never launch and it is safer to sail downwind this
way than to risk having a good spurt of speed and then crashing and losing 30 to
60 seconds in righting the boat
3.14 Tacking
In order to tack a Bladerider, it is important to keep it airborne as long as possible.
Basically the skipper should slowly point to windward and move the weight inwards, until the
boat hits head to wind. At that stage the boat and the leeward wing will hit the water killing a
majority of the speed. The skipper must quickly jump on the new windward bar to pull the rig
over on top of them and keep the leeward wing from going under water.
Bear away past close hauled as quick as possible to get power in the sail and speed up.
The boat should accelerate up to 8-10 knots on a tight reach fairly quickly, and when doing so,
the boat will lift out of the water. At this point the skipper should heal the boat over to windward
and point up to close hauled at the same time.
3.15 Gybing
It is important to keep the boat with no heel, but a slight amount of pitch up on the bow.
This is because when you move to slow down through the gybe, you will need more lift by angle
of attack to keep the boat altitude up.
If the boat starts to heel to one side or the other, straighten the boat up with small tiller
movements (or use slightly more pressure on one side of the hull) until it comes upright. Then
continue the turn right through to about 90 degrees to the true wind. Once the apparent wind
comes around, then bear away with it.
It is important the skipper does not change hands with tiller and mainsheet during the
gybe, until the boat is settled down and is sailing fast again on the new gybe. The whole time
during the gybe, the boat cannot heel over otherwise it will easily lose balance, the wings hit the
water, kill speed instantly and potentially tip you over.
Good luck and have fun! ☺

http://www.teknologika.com/mothblog/wp-content/uploads/Guides/sailing_the_bladerider.pdf

simba_the_sailor
27 Jan 2015, 09:33 AM
https://www.youtube.com/watch?v=5i9aechETtk

https://www.youtube.com/watch?v=FlQi0Vxh1-w

https://www.youtube.com/watch?v=vZHA3ZpO9E8

https://www.youtube.com/watch?v=OtM31L_ba0I

https://www.youtube.com/watch?v=RF5ZH-J0ZBQ

https://www.youtube.com/watch?v=v_B5fWO_4rw

simba_the_sailor
27 Jan 2015, 09:42 AM
https://www.youtube.com/watch?v=t6PmeqFa3nA

https://www.youtube.com/watch?v=4cuZkpiRLTg

https://www.youtube.com/watch?v=RABxXlwRfAc

https://www.youtube.com/watch?v=an-2M29l17M

https://www.youtube.com/watch?v=7NiwwHvTh2s

https://www.youtube.com/watch?v=Bd4gksY2sQw

https://www.youtube.com/watch?v=8YuCM0rfq88

https://www.youtube.com/watch?x-yt-cl=84503534&x-yt-ts=1421914688&v=aMz6mxj8Es0

simba_the_sailor
27 Jan 2015, 11:42 PM
nick flutter's moth design blog (http://nickflutter.blogspot.ca/)

simba_the_sailor
24 May 2015, 12:34 AM
https://www.youtube.com/watch?v=7M_98Pbkkcs

Din atatia mesteri mari, kalfe - marinari, pana acum nu s-a gasit vreo unu' sa construiasca vreun kayak, o canoe sburatoare, ceva :D