Thanks alot John, just what I was looking for :

Your comparison seem to run parallel to that of Stealth vs Taipan for a long way.

A few quick comments :



What do you mean exactly by this. The hulls are less high ? Or just the very front part ?




Here too we see two entirely different design approaches. It appears that both work. Interesting.





That is a pitty. The rudder board profile as supplied by VWM is of a noticeable better section than the AHPC ones. You would have had full control at all manouvres with the other ones. I have the AHPC ones myself and while they are generally good sections, you can make them stall (lock-up) during some more extreme manouvres. Still it; appears you had more trouble with steerage then is normal for well alligned AHPC rudders.





After having raced the Stealth F16 in several day/heats I feel that no boat without T-foil rudders can feel as rock solid as the Stealth F16. You really can just ram the boat downwind and do your thing on the trampoline, the bows will simply not dig in no matter what. I don't know about the payback though (loss in speed ?) but I much rather loose some speed momentarily then risk a deep dive with possibly a capsize. I remember that during the race we eventually wouldn't even pay attention to the bow anymore. We would just round the bouy, get of the trapeze dive forward and start pulling the kite. This in itself is racing advantage in my book. On my Taipan we need to time the bear away and following actions with the movement of the bow section.

I'm absolutely convinced that the T-foil rudders are the reason for the solid feel of the Stealth. Besides John this is easy to test really. Just lend yourself a couple of daggerbaords of a fellow Stealth owners and slide this in your rudder stocks instead of the T-foil ones.





Yep, say no more, those are AHPC rudders alright.





A wild guess here : Your downhaul was on still tight and the top of the mast was hooking the water OR the wind = Standard Superwing behaviour and entirely preventable. The squaretop top is still standing up too much.

I've encountered this behaviour myself a few times. The rig is not cut loose enough. Run mainsheet traveller out (all the way) first, then run out as much mainsheet as there still is left, then completely slack the downhaul, possible running it out with your hand a little bit. THEN Shake the mast a little using rotation arm (mainsail will unjam herself in the mast). Now she will come up as expected. 10 seconds max. If not then release the outhaul (along the boom) as well and make sure the bolt rope is not jammed right about the goose neck.




There should be a system to raise the boards, this should also keep the boards on board during a capsize.




It is true then. Different design approach then usage of T-foil rudders but it works.




That may well be an excellent cross polination between the two designs.




I always thought the Stealth to feel much stiffer then one would expect by looking at the beams themselfs. I was surprised at that myself. I also suspect that SIN 708 can be made stiffer easily by having (halve) disk like inserts underneath the outer bolts, in both beams. See close-up of mainbeam. With this the walls of the beam are really jammed up between the inserts and the beamlanding and can't flex.







Thanks alot John,

I will from now one refer interested parties to this report.

Wouter