59er Sails - very flat

We have a 59er in our club (Wilsonian).  The sails seem very flat.  The main is now much better since we have reduced the caps to 10 on a Loos gauge and the mast is now not so curved.  The jib however is extremely flat, the top batten straight and you have to come down the sail about a 1½m to see any sign of curve.  We have tried loads of luff tension.  Any ideas?  Or do any 59er sailors recognise this.  I'm trying to get a photo  from the owner but I hoping to beat the owner to a solution.

They are much flatter than my Laser4000 which has very similar speed.

Make sure you have the lowers pulled on so the bottom of the mast is dead straight when you apply rig tension.

We basically couldn't measure the uppers with a loos guage.(They were that slack) We felt that pulling them on stopped the boat from breathing. We left them on the same hole for all wind ranges as they automatically loosened when you increased rig tension on the primaries when it was breezy.

There's a principle being established that larger flat sails are easier to handle than smaller full ones for the same power. Hnece the 59er has relatively large sails for the righting moment etc available, but they flatter.

The flat sails also produce less drag - which is all part of the philosophy of the boat- the hull has a bit more rocker/deadrise and relatively long chines on a relatively narrower immersed hull making it slippier than the 29er/49er.

I reckon swiftsolo risks a bit with his upper D2s being slack-alice - but I presume the windward one comes tight when sailing(?)

 

I think "design wind" for the boat must be about 9 knts (with lard at 150-180kg !)  and there after you are depowering the already flat sails! Low and fast is the aim- don't try to point.

If you can invest in a dinghy-speedo,  or have a GPS, you should be able to do 7/8ths of windspeed upwind in up to 12 knts breeze, and almost up to 1/3rd faster than the wind on the "run".

Swifty can tell you more about higher winds, but I just remember bombing down over the wave train wearing a grin and being able to chill out!