I can see that it suffers some of the issues we found with the canting sail on the model proa.  The loose luffs is the most obvious.  With the canting sail, that was overcome by fitting wire in the luffs and making the sail with its own spar and bottom bar that enabled the luffs to be tensioned independent of any sheeting.  That spar was supported roughly in the middle on a yoke mounted on a stubby mast so that when the sheets were released the sail would fly to horizontal.  Being supported at mid height meant the heeling moment of the released sail was low.  We could sail it quite close to the wind before the luff fluttered but control over the AoA reduced as the sail got closer to the horizontal because we could not control the sheets individually.  Once the sail is canted the AoA attack is a function of both horizontal and vertical rotation.

The kite-like shape of the sail meant it remained stable once it was unsheeted.  It did not flog about like a normal sail where the material is loose to flap and flog when  unloaded.  I can imagine the Bolger rig being a beast when the sheets are released because it has the heavy curved batterns that could develop substantial momentum when flogging.

The concept of the square rig was much closer to that on Maltese Falcon with yards held, but not rigidly fixed, to the mast and the sail made of individual panels.  There was intended to be 5 panels each 3m high.  The bottom panel width was 8m then 7, 6, 5 and 4m at the top.  That gave a total area of 90sq.m.  Each panel would have its own sheets at the end of each yard.   During a shunt the pressure on the rig could be reduced substantially but not completely 90sq.m of sail blowing in the breeze will still have a good amount of drag. 

Rick

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