AS USUAL WEEZY IS ARGUING ABOUT SOMETHING THAT WAS NOT SAID OR IMPLIED. HE JUST DOESN'T UNDERSTAND ENGLISH VERY WELL.

>>The Marstrom A Class hulls are famous for their strength.

This is not a correct conclusion from this test. As a matter of fact Booth made skilled use of how the design parameters behave when loading up a platform.
WHO SAID IT WAS FROM THIS TEST? THE MARSTROM HAS BEEN FAMOUS FOR MANY YEARS FOR STRENGTH. WHY DON'T YOU KNOW THIS?

Let me run through the points


>>Is 2.5m wide, instead of 2.3m,
: Does not seriously increase loads on the platform.
I DIDN'T USE THE TERM "SERIOUS", YOU DID. BUT YOU AGREE THAT LOADS ARE INCREASED.
the increases are accompanied by equal magnitude reductions.
ONLY IF NOTHING ELSE CHANGES.


>>The mainsail is 15sm instead of 13.94sm,
; Doesn't matter ; righting moment determines the laod on a platform not the sail area.
WRONG! A SAIL IS SUBJECT TO INSTANTANEOUS LOADS FROM GUSTS AND OTHER SHOCKS. YOU NEED TO LEARN ABOUT "ACCELERATION". YOUR SIMPLETON STATIC CALCULATIONS DON'T DETERMINE MAXIMUM LOADS. COMPARE THE INSTANTANEOUS LOADS OF A SLOW FLIP TO A VIOLENT PITCHPOLE.
Amount of sailarea only determines how much more you need to depower a rig at the same high wind conditions
WRONG!! SEE ABOVE


>>The boat weighs 78kg instead of 73 kg,
; This is neglectable
NO DUH!!! THAT IS MY POINT. THE ONLY WEIGHT GAIN IS CAUSED BY THE ADDITIONAL EQUIPMENT.


>>And of course it has a 15sm gennaker.
;Spinnaker does not introduce higher loads on the sidestay than when sailing upwind.
I DIDN'T SAY "SIDESTAY". SUPPOSEDLY, WHEN SPINNAKERS HAVE BEEN TRIED ON SOME A CLASS BOATS THE SIDE LOADS RIPPED OFF THE WINDWARD BOW.
It does not load the hulls up more than a jib does on the same upwind course.
THE SIDE LOADS ON THE BOWS FROM A SELF-TACKING JIB ARE MICROSCOPIC COMPARED TO A SPINNAKER.
I haven't done the calcs on mast compression yet.
DON'T BOTHER, IT WILL BE WRONG.
Mast foot and beam however are unimpressed by a spinnaker. The increase in load is simply to small when compared how much a beam is overdimensioned to get the optimal beam stiffness. Beam is never in risk of breaking only flexing to much.
MARSTROM ALREADY CALCULATED THE LOADS AND BUILT THE BOATS AND THEY DIDN'T BREAK. WHO ARE YOU?


>>The hulls didn't break.
: The hulls are build to resist shock and point loads this make the hull alot stronger than necessary for the sailing loads.
NO DUH AGAIN!!! REMEMBER, I SAID "FAMOUS".
Only serious point of concern are the sidestay chainplates.
These do experience increasd loads to 170% to 200 %
WRONG, WRONG, WRONG!

>>The mast didn't break.
: It was a M20 mast ; it was designed for double trapeze spi use.
NO DUH THREE!!!

>>The daggers didn't break.
: This is interesting,
WHAT DOES THAT MEAN?
These see increased loads to again 170% - 200 %


>>The rudders didn't break.
: Rudders are less critical than the daggerboards. so if the dagger hold ..
WRONG!! YOU CAN'T RACE A BOAT VERY WELL WITH BROKEN RUDDERS.

>>The hardware didn't break.
: Yes well, that is because for small open boats there is pretty much one line of breakstrength used on all boats from 14 foot to 22 ft.
WRONG!! THAT IS YOUR MOST RIDICULOUS STATEMENT YET. IF YOU ATTENDED REGATTAS YOU WOULD SEE THE DIFFERENT SIZES OF HARDWARE ON THE DIFERENT BOATS.

>>I think the issue of strength has been resolved.

Yet but the issue of flexing hasn't.
WHO SAID THE MARSTROM HAD A FLEXING PROBLEM? EXCESSIVE FLEXING OF A COMPOSITE MATERIAL CAUSES EARLY STRUCTURAL FAILURES. WHEN HAVE MARSTROMS FAILED?
For example It is not difficult to design a mast thatwon't break but it is difficult to design a mast that won't break and flexes in the right way and to the right amount to make a boat well behaved.
DID YOU FIGURE THAT OUT YOURSELF OR DID YOU READ ONE OF THE HUNDRED DISCUSSIONS ABOUT THAT SUBJECT?


>>The boat was used for a couple of weeks max and it has not broken yet.

This is also interesting as indeed damage to beams and other stuff is nearly always the result of metal fatigue and low tension ruptures.
WHO SAID? WHAT ARE YOUR SOURCES FOR THIS STATEMENT?
These two do require above anything else "time". Still I trust Goran to design his products in such a way that both failing mechanism are unlikely to occure on his boats. Mostly these tow failing mechanisms are the result of lapses in design.

Wouter

PITIFUL, JUST PITIFUL!!!