Page 1 of 2

Upwind angle

Posted: Mon Jun 14, 2010 7:53 pm
by pouch
hi,


I have started recording my race trainings using a gps and GPS action replay to post process the data.

a fair calculation (over500m) of my upwind angle would give me around 55 degrees.

do you have any ideas of your angle ?
do you have an idea of the best angle of top riders ?
what about other sailling machines windsurfing boards, saillling boats ...


thanks in advance

Re: Upwind angle

Posted: Mon Jun 14, 2010 8:28 pm
by Laughingman
Can you illustrate what you mean by a 55deg upwind angle?

Re: Upwind angle

Posted: Mon Jun 14, 2010 8:39 pm
by pouch
Image

Re: Upwind angle

Posted: Mon Jun 14, 2010 8:42 pm
by dr.lojz
Laughingman wrote:Can you illustrate what you mean by a 55deg upwind angle?
Wiki says
http://en.wikipedia.org/wiki/Points_of_sail
http://en.wikipedia.org/wiki/Sailing

Typical angles to the true wind are as follows. Actual course over the water will be worse due to leeway.

* about 35° for modern racing yachts which have been optimized for upwind performance (like America's Cup yachts)
* about 42 to 45° for modern cruiser-racer yachts (fast cruising yachts)
* about 50 to 60° for cruisers with an emphasis on interior space, ease of handling and often low draught rather than sailing performance, and for boats carrying two or more masts (since the forward sails adversely affect the aft sails when sailing upwind)
* close to 90° for square riggers and similar vessels due to the sail shape which is very ineffective when sailing upwind

dr.

Re: Upwind angle

Posted: Mon Jun 14, 2010 9:11 pm
by Laughingman
Awe okay got it. For some reason I was measuring from a point perpendicular to the wind, 55° was a bit over zealous! Now I understand how it should be measured.

Re: Upwind angle

Posted: Mon Jun 14, 2010 10:46 pm
by alexrider
pouch wrote:hi,
I have started recording my race trainings using a gps and GPS action replay to post process the data.
....
thanks in advance
Interesting topic Pouch! :thumb:

Could you post the Polar VMG graph from GPS action replay?
What board and kite are you using?
I suggest that sea state and wind conditions should be sated as well, for fairer comparisons. Chop, current etc.. affects upwind angle a lot.

See you in Bali as all the others at TLK! ;-) :cool2:
Flat water in the Sanur Lagoon, AND good waves on the reef.
Local ace Jankie is organising races every Sunday of June till end of season.
Come on Frenchies, and show your skills in the Island of the Gods.
:bye:
Alex

PS: would you dare to show your TLK avatar on kiteforum? :jump:

Re: Upwind angle

Posted: Tue Jun 15, 2010 3:52 am
by Kamikuza
At this stage, I'm ecstatic if I get back to the point on the beach I started from :D

Re: Upwind angle

Posted: Wed Jun 16, 2010 1:49 pm
by holden
very interesting topic! the polar diagram i posted is the latest testrun with my doityourself raceboard. three fins and the frontfins with twistcut. upwind performance ist quite well. downwind i have to try one or two more modifications to make it better controlable.
kite: speed3 12 dl
wind: 90% weak up to 10% medium.
waves: small chop.
polardiagram: gpsar 3.3.3 free

Re: Upwind angle

Posted: Wed Jun 16, 2010 7:43 pm
by pouch
really impressive Holden , what a great kite you have :thumb:

Saint Aubin sur mer / France
15 -25 knot gusty
choppy / no waves
kite : Psycho IV 10 sqm

Image

Re: Upwind angle

Posted: Wed Jun 16, 2010 8:10 pm
by pouch
alexrider wrote: What board and kite are you using?
See you in Bali as all the others at TLK! ;-) :cool2:
Flat water in the Sanur Lagoon, AND good waves on the reef.
Local ace Jankie is organising races every Sunday of June till end of season.
Come on Frenchies, and show your skills in the Island of the Gods.
PS: would you dare to show your TLK avatar on kiteforum? :jump:

at that time i was using an old race board 198x43 (2x 21 cm front fins / 2x15 cm back fins)
JBK (alex cazairgues shaper)

I am starving to visit you in paradise !

My avatar is now turned On :rollgrin:

Pouch