B&R Rigs

Dear Steve and Linda: I’m not going to go on about the profound influence your work has had on my wife and I, nor will I bore you with how much we appreciate your efforts–we’ve sent a separate letter for that 😉 I have a question concerning the B&R rig. We are slowly getting together our “ideas book” for a 70-foot aluminium ketch and it occurred to me that twin B&R rigs would offer many advantages. In addition to their survivability (HUNTERS CHILD testimony) I figured the absence of any true backstays would allow much scope for a range of "reaching sail" possibilities on the mizzen. The full roach, full batten mains are also appealing. I understand the limits with the 30-degree spreader angle, but figure that even with the wind dead astern we would achieve 85% plan form. Judging from what you said in your offshore video we figure we’re more likely to want to head up a little, use the reachers/spinnakers and get more ventilation through the boat anyway.

Getting to the point slowly…Deb and I have just married and we chartered a Hunter 41 for two weeks in the Whitsundays–largely because of the B&R rig and also because we wanted some experience in a bigger boat with just the two of us. Though we had a great time, we were a little disappointed. On the couple of days it reached 25kts gusting low 30s, the headstay would slacken severely reducing our windward performance and introducing a lot of unwelcome heel. I understood that the B&R rig was originally designed for a hydraulic vang (though I know HUNTERS CHILD had a solid vang). I figure a hydraulic vang may help solve this problem? It could also have been the barrel of the furl system (ProFurl) on the headstay bending around an otherwise solid stay. Is this possible? Can you think of any engineering problems with the rig if we were to fit a removable inner forestay, given there is no easy adjustment in the rig once tuned? Is there an information resource you know of where I might research this further? I welcome any comment you may have on these matters. Take Care, Gair and Deborah, Perth, Australia

Hi Gair and Deborah: Thanks for the kind words. The B&R rig is very efficient and the weight savings can be substantial. Regarding headstay tension, this is always an issue without some form of tensioning device. We’ve taken a different approach with our backstayless rigs. We use 25-degree spreader sweep, and then a masthead running backstay which serves two purposes: First, it gives us good control over mast bend (which you do not have with the Hunter approach to B&R). Second, it controls headstay sag and thereby headsail shape. This is what we’ve done on BEOWULF, and on our Sundeer 64. Coming back to your B and R approach, you can do the same, i.e., add a set of runners for both bend and headstay control, but of course you would want to check the details with Sven Ridder.

Posted by Steve Dashew  (November 30, 1999)

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