Starboard Forums

Starboard Forums (
-   Ask Our Team (
-   -   light winds board/sail (

costap 14th March 2012 08:04 AM

light winds board/sail
Hi guys,

I currently own an isonic 107 wich I use with sails from 6.2 to 8.3 and it works great for winds from 11 knots to 35 knots.

I looking for a new setup for the lighter winds, 6 to 15 knots? I was thinking maybe a Ultra Sonic 147, or a Formula board, or even a larger isonic?

And for sail, 9.5 or 10?

What would you advice?

I am light guy, 60Kg and I don't race, it's just for fun.

Thanks in advance for your help!


joe_windsurfer 14th March 2012 09:51 AM

you are a lite person at 60 kilos
butt to "sail" in 6 knots ??
i have a racy longboard and usually donut go unless winds are around 10 knots
so, in my book , you are covered :)

Roger 14th March 2012 12:22 PM

Hi costap,
The UltraSonic 147 will get a lightweght planing in 8-9 knots with a good 9.5 m2 free race sail (more draft than a race sail for low wind power).
Below a fairly steady 8 knots, even at your light weight, you will not plane, so the only choices are some sort of longboard or the Serenity for smiply cruising around.
Hope this helps,

costap 14th March 2012 03:24 PM

Hi guys,
How about a Formula board? Would that give a bit more of early planing?
At my local place we have lots of days (specially in spring/summer time) of 8~12 knots, would be great to find a sail/board for these conditions.
Serenity really looks cool and I am sure is a great board for cruising but not sure if I could manage the storage...

Roger 15th March 2012 02:06 AM

Hi Pedro,
Formula boards are a bit more technical to sail and require larger (longer/deeper) fins to perform well.
They will plane as early if not earlier than the US 147, but may not be as much fun as they are completely designed for upwind downwind racing.
The US 147 is a bit more slalom oriented....better for back and forth reaching.
Won't go upwind as well or as deep downwind, as the formula race board, but unless you are racing,
most sailors never need to go that high or that low, especially in marginal < 10 knot conditions.

costap 15th March 2012 07:24 AM

Hi Roger,
That helps, thanks. I think I will look to get a US 147 as a complement to my 107.
What sail size would you recommend for this board and my weight, the 9,5m2 (3 battens free race sail)?
Does it worth to go a bit bigger, 10m2 (4 battens full race sail)?

mcross19 15th March 2012 09:00 AM

Hi Pedro, I use the 147 from 11m down to 8.5m and that works perfectly. At your weight a 10m sail should be fine as a max size sail. Martin

joe_windsurfer 15th March 2012 09:49 AM

planing in 11 knots down to 8-9 knots on the US 147
gain of 2 to 3 knots and probably unsteady winds
also, add a large sail with cambers, high carbon mast and perhaps carbon boom
brand new - board, sail, mast, and boom has to be around or more than $3000

is it worth the investment ?? ROI ??

mcross 19 - how "easy" is it to plane in these really lite winds ??
how much pumping ??


Jean-Marc 15th March 2012 01:53 PM


This is what I've tested with my 65 kg:

Lower wind range:

1) Formula + soft 70 cm fin + Code Red 11.0 m2 sail : start and sustain planing as of 6 knots.
2) Ultrasonic + 62 cm fin + Code Red/Refelx II 11.0 m2 sail : start and sustain planing as of 7 knots.
3) iSonic 127 + 55 cm fin + Refelx II 11.0 m2 sail : start and sustain planing as of 7 knots.

Upper wind range:

1) + 2) + 3) remain in full control up to 12 knots steady wind. With a narrower board (HS105) + 55 cm fin, it's still under control up to 15 knots peak gusts for my light weight.

The lower wind range between a North S-Type 9.5 and a Severne Code Red/Reflex11.0 m2 sail is quite significant but irrespective of the board + fin size combo : 2 knots later with a 9.5 m2 sail; 3 knots later with an 8.5 m2 sail as compared to that with an 11.0 m2 sail.

The Serenity is quite special as it doesn't plane as a true planing board, i.e., cannot climb over her own bow wave and accelerate further and further (topping speed is about 13.5 knots board speed, not higher). Wind range with an 11.0 sail and the stock stiff Drake 70 cm fin : 2-8 knots wind; board speed is twice that of wind speed. Check following movie of Serenity + 11 m2 sail on a fresh water lake in 3-5 knots wind ( and in 5-7 knots wind (

You might think an 11.0 sail is too big for a 65 kg, but once sailing, it's no big differenece with say an 9.5 or a 10.5 m2 sail in the hands. As for my home spot where I usually have 2-7 knots almost 3 days a week and 7-12 knots almost 2 days a week between March and November, the addition of an 11.0 sail to my sail quiver has increased the number of planing session by a factor of 2. The addition of the Serenity has increased the number of gliding session by another factor of 2. With that quiver, I can go windsurfing when I have a free time slot, and not when there is wind. That's a huge improvement in quality TOW and efficient time management outside the office: no more wasted time sitting on the beach and waiting for a minimum wind limit to materialize. Sure, the Serenity, 550 cm mast, rolled 11.0 sail and long boom are large items to lugg and carry around, but it has been worth the trouble since 5 years: no pain, no gain.

Cheers !


Jean-Marc 15th March 2012 02:17 PM

Different hull geometries for different wind range usage at gliding or planing state:

The Serenity nose pitch when gliding at her topping speed (460 cm long where the second half 230 cm are on the water) :

Compare that with the nose pitch of a true planing hull (227 cm long where only the last 50 cm touch water) :

Cheers !


All times are GMT +7. The time now is 02:46 AM.

Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.