Re: B&R rig
As designed and rigged correctly, a B&R rig has no backstay because it isn't needed and would only overly complicate the tuning process and the stresses applied to the spar.
When my dad drew the original Hunter 54, he did as Lars and Warren suggested and designed it to have no standing backstay. The production boats began that way; but customers were so mistrustful of the rig as it was designed by experts that Hunter kowtowed to them and added a backstay. The backstay, at least in theory, does not have the ability to provide mast bend-- to attempt that on a true B&R rig would be to push the mast heel through the deck.
The whole key to a B&R rig is stiffness; though, of course, if improperly tuned, such a rig (as with any rig) would be worthless. Most people not understanding this will blame the rig for being insufficient or 'finicky' when nearly always some fault can be found for how it has been tuned, maintained and repaired.
Hunter later used the B&R rig for some of the smaller boats, notably the trailerable 24 which was able to boast of having only 'three' rigging wires to connect-- the forestay and the common pins for port and starboard upper and lower shrouds. This perhaps exaggerated the simplicity of the rig design but did demonstrate its inherent benefits-- that of providing requisite stiffness via only a few (albeit key) points. This is also a drawback as these few points must be very, very well cared-for or they will rapidly become the boat's biggest (and perhaps hidden) Achilles heel. At the age some of these boats are now attaining this becomes a vital issue.
BTW: at Cherubini we encountered the same problem with C48 staysail schooners, which dating back to my Uncle Frit's 1985 'Legacy' (the original wooden plug) were meant to have a pure B&R rig for the main. It's an excellent example of how to apply this rig as it avoids the need for a standing backstay and the ugly boomkin. But straight out of the box the first 'production' boat was stipulated to have a boomkin and backstay because of the buyer's *assumed* (and, implied, superior) expertise in sailboat rigs; and this became too much the norm. I don't know why-- none of John Alden's famous schooner designs had boomkins or standing backstays; and they weren't exactly known for automatic dismastings during every jibe. At a certain point it comes down to the sailor's having a sufficient comprehension of the sailboat itself.
The C48 'Antonina', kept at Hancock's Harbor, NJ, is the purest one I have seen, having the split cabin houses, off-center prop and B&R rig. It's a thing of beauty, the best example of the type. Would that all C48 and H54 buyers had trusted my dad a little more!
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