The point is that when you are stopped for a shunt you have first airflow over sails and pressure on the sails. If the rudders are not already in position for that tack the pressure on the sails will not start moving the boat forward but turn it to the wind. You need reasonable balance to have the boat move forward. If not you will only turn the boat to wind due to too much weatherhelm. Once the boat is already moving rudders will be more effective and counter the weatherhelm.   Arto Not the owner of ONO, have sailed once on ONO though... --- On Thu, 5/27/10, Gardner Pomper <gardner@networknow.org> wrote: From: Gardner Pomper <gardner@networknow.org> Subject: Re: [harryproa] new rudder concept To: harryproa@yahoogroups.com.au Date: Thursday, May 27, 2010, 2:14 PM   Hi, I thought that the harriette rudders used the flow of water to tilt back. Aren't they asymmetrical? My impression was that you have no steerage until the water starts flowing past the rudders, so it wouldn't matter until you got up to a knot or so, so if they tilt back at that point, you would be ok. - Gardner On Thu, May 27, 2010 at 2:57 AM, Arto Hakkarainen <ahakkara@yahoo. com> wrote:   Two comments on Gardner's proposal:   1) The most critical moment when you need to foils back and rig forward of the foils is when you start moving. Counting on water pressure to move the foils to right position will not work. Have been tested and never succesful as far as I know. You need the foils on new tack before the boat starts moving. Before the boat moves there is no water pressure to move the rudders.   2) The square shaft and the rudder foil mounting will hit the waves which will lead to resistance through water and stress on the rudders.   Arto --- On Thu, 5/27/10, Doug Haines <doha720@yahoo. co.uk> wrote: From: Doug Haines <doha720@yahoo. co.uk> Subject: Re: [harryproa] new rudder concept To: harryproa@yahoogrou ps.com.au Date: Thursday, May 27, 2010, 9:41 AM   Rob's Sol rudders are the best design so far for strength simplicity and ease of retracting.   Doug  --- On Thu, 27/5/10, gardner.pomper <gardner@networknow. org> wrote: From: gardner.pomper <gardner@networknow. org> Subject: [harryproa] new rudder concept To: harryproa@yahoogrou ps.com.au Date: Thursday, 27 May, 2010, 12:00   Hi, I just posted Rudder.pdf under Gardner's Layouts in the Files section. I keep wanting to use asymmetric rudders, so here is another drawing about how it might work. The rudder blade has a pivot pin near the top (maybe 6") that the rudder can tilt forward and back around, due to the water pressure of the moving boat. There are sacrificial break-away pins fore and aft that keep it from tilting too far. This is all attached to a rudder mount that has a square rudder shaft attached to the lw side. This square rudder shaft can be raised and lowered vertically. It goes through a stub steering arm that gives teh steering cables some leverage to point the rudder +/- 30 degrees (or whatever is reasonable). Then the whole bit is attached to teh lw hull through a brace mechanism similar to what Rob is doing on Solitarry, except that it is fixed in position, so it can be made as strong as required. So, comments? - Gardner