kitesurf for dummies v2.0

Kitesurfing for dummiesV2.0

oliver.dewolf@howest.be

2800 years ago in China there once was …

SILK & BAMBOO549 ADfirst recording with paperdifferent usesmusic & mythical figures

Time and technology let men become creative with kites…

And somewhere in 1977 a new sport was born…

B

KITES + SURFING = KITESURF1985 floatable parts1994ControlbarssurfboardMaximum use winddirection

So what is it...?

how is that possible...?

NEWTONS For every action there is an equal and opposite reaction. Kites excert a downward force upon the air. Air passes over the top edge of the kite and goes down the upper surface of the kite. As the kite pushes downward on the relatively heavy air it gets an equal push upwards. This causes the kite to have an upward counterforce and to fly.

BERNOULLIAs the speed of a fluid increases, the pressure in the fluid decreases. As air passes below the wing it also passes above the wing. The air on top of the wing moves a longer distance over the curved surface of the wing and moves at a faster speed. This reduces the pressure above the wing. The air below the wing moves slower than the air above the wing. This causes the air pressure to be increased. This difference in pressure above and below the wing causes a kite to fly or lift.

2 LAWS

3 MAIN FORCESLIFT

Like an airplane, a kite is heavier than air and relies on the motion of the wind past the kite to generate the aerodynamic lift necessary to overcome the weight of the kite.

DRAGThe movement of the air is generating an aerodynamic drag

which is overcome by constraining the kite with a control line.

GRAVITYThe aerodynamic lift is overcoming the weight of the kite and the person hanging.

(both a downward force)

those jumps…?

UPDRAFTS AND TERMALS

A kite also gets higher by updrafts and thermals. Updrafts are formed when the wind rises over the kite's surface. Thermals are rising bubbles of hot air.

But, you need the right conditions …

ONSHORE WINDS

And the right training for control…

WINDOWlaunchsafetyWater startPosition of the kite

STEERING LEFT/RIGHT

Pull left, to move the kite to the left side of the window. The opposite happens when pulling right

ANGLE OF ATTACKMovement of bar (back and forth) results in change angle of attack

Change angle of attackResults in less or more power

KITE SAFETY SYSTEM

Power needed to release chickenloop < 4 kg at 200kg

Total depoweredSafety loop last option for total release

Full power kite

and high end materials…!

CANOPE (NORTH 2008)

Technoforce T9 polyester ripstop UV-protected coatingAramid reinforcedUV-obstructing polyester polyurethane bladdersLeading edge in Dacron

TRUSTBAR (NORTH 2008)

Metal centerDyneema Technoforce T9 polyester ropeProtective rubber coatingComposite interiorEva Grip

HARNASWater, salt and impact resistant

BOARD (NORTH X-RIDE)

ABS protected sidewalls3D wood carbon sandwichCNC milled 3D deck and bottom (flex) Adjustable footstraps

SAFETY LEASH (NORTH)

Stainless steel buckleNeoprene Covered BuckleDyneema Rope Inside250kg holding karabine

PUMP (NORTH)

piston pumpcapacity of 2 x 2.000 cm³

WETSUITneoprene

1st Kite 1100,-Bar 300,-Harnas 100,-Pump 30,-Safety leash 20,-Board 600,Subtotal 2150,-Surfsuit 200,-2nd kite 1100,-Total 3450,-

cost