Fraz
New member
Has anyone understood how to apply the YTC Non Spinnaker correction formula please??
i.e 1.75-(DSA/SA) THS IS WHAT IS PUBLISHED BUT IS THERE AN ERROR MAYBE?
Example to test it
Dehler 34 1.76 (101) DSA 103.6SQM (Downwind sail area) SA 55.90 SQM (Upwind sail area)
so you get 1.75 - (103.6/55.90) = -0.1046366 do i then need to add 1 to this number to make 0.895 ??
But 0.895 is wrong i need to get approx 2.59% difference to apply to the YTC rating for 2023 is 925 and white sail is 949 (24 points difference)
So ideally i need to multiply 925 by 1.025 = 949, but i cant get 1.025 from 1.75 - (103.6/55.90)
I have got the 1st part of the formula working well, then i apply any Propeller change from fixed 2 blade and this works fine.
I just do not understand how to calculate the Spinnaker % change and apply it....
Can anyone help please and show me an example based on the above that works out to give 949 from 925 the based value.
Also noted the formula for calculating YTC has changed from 2023 to 2024, but i have that all working fine except the spinnaker correction
i.e 1.75-(DSA/SA) THS IS WHAT IS PUBLISHED BUT IS THERE AN ERROR MAYBE?
Example to test it
Dehler 34 1.76 (101) DSA 103.6SQM (Downwind sail area) SA 55.90 SQM (Upwind sail area)
so you get 1.75 - (103.6/55.90) = -0.1046366 do i then need to add 1 to this number to make 0.895 ??
But 0.895 is wrong i need to get approx 2.59% difference to apply to the YTC rating for 2023 is 925 and white sail is 949 (24 points difference)
So ideally i need to multiply 925 by 1.025 = 949, but i cant get 1.025 from 1.75 - (103.6/55.90)
I have got the 1st part of the formula working well, then i apply any Propeller change from fixed 2 blade and this works fine.
I just do not understand how to calculate the Spinnaker % change and apply it....
Can anyone help please and show me an example based on the above that works out to give 949 from 925 the based value.
Also noted the formula for calculating YTC has changed from 2023 to 2024, but i have that all working fine except the spinnaker correction