[MHml] [Harrys, heavy weather and jordan drogues

[rob dalton]

  At last count there are two Harigamis, two Visionaries, three Elementaries sailing, and one Harry just completing its rig ready to get wet. The last one is getting ready for crossing the Tasman. No really heavy weather so far but a Visionarry was unconcerned with crossing bars and moderate seas. They have behaved themselves pretty well so far. Feel much more confident in their seaworthiness than any of the fishing boats I worked on in Bass Strait.( Not an enormous recommendation as two have since sunk and one split its seams at sea) Not sure about having the wing masts in a blow .
  For heavy conditions, the idea is to let out some of the drogue over the back when things start to get out of control and when I need a rest, let out some more. None of this standing on the pitching foredeck motoring into seas trying to set a parachute, though there is still the hassle of the bridle. The way I see setting the bridle is to have it slightly off set so that the boat is slightly skewed with the ww hull kept slightly to ww as that is minimum windage and better balance to the waves.
  800kg and 9mww hull/13.5m lw hull, 7.5m wide. Will it simply be picked up and blown away? In a category 5 cyclone like Monica up here early this year with est. 360km/h winds,  probably (Northern Territory, Australia- http://www.bom.gov.au/announcements/sevwx/nt/nttc20060417.shtml). Anything less, I hope not. This  is why I want a decent sea anchoring system.  800kg and 9m/13.5m  is light for the length but the long hull is like having the two outriggers on a tri into one long one and there will be stores and people on board- most of this extra weight to ww increasing righting moment and fore aft stability on the diagonal. The windage is not commensurate with the length compared with other many other multihulls but the fore aft stability is. 
  Whether to go with wing masts or not depends on Rob's sea trials and they will need to be balanced in terms of their centre of wind resistance, moments of inertia and restitutional force to avoid flutter. If they work well they provide a self righting system for a 90 degree capsize from over zealous sailing, and if they survive a full turtling, make the turtled boat come close to self recovery with a bit of wind and  wave action. 
Regards, 
  Robert


 		
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