Feathering prop for 69' Bristol 40

[sv.antea]

Feathering prop for Bristol 40.
Over bunch of years I have been upgrading all systems on friend's 1969 Bristol 40 yawl. Recently she got new sails and she really started to shine in local club racing. That brought me back to the prop problem. We looked briefly into replacing her fixed three blader with MaxProp few years back when she was hauled, but concluded that there was not enough room. Recently I have been seeing many new ads for various feathering props in the sailing magazines and I wonder if the hub length and blade width of one of them may be small enough to fit (with minimal modifictions) the available apperture.
The bad news is that 69' Bristol 40 is full keel/centerboarder, the rudder stock is 30° off vertical and the elliptical apperture was designed for prop to go with the original Atomic 4. Now she has Perkins 4-108 with no reduction gear. Motors adequately. Any feathering props with shortish hub and narrowish blades anyone knows about?

[Blue Stocking]

Have the same situation with my Rhodes Reliant 41. No luck yet.

[roverhi]

Doubt that a feathering prop on a full keel boat would make any significant difference in its sailing performance, especially when you consider Cost/Benefit. There is so much resistance and turbulent water by the time it gets to the prop from the wetted surface of a full keel boat that the minimal drag of a prop hidden behind all that deadwood or a feathering prop won't register.

Delivered and cruised on 3 Westsail 32s, one with a two bladed prop with the prop stowed vertically behind the deadwood and two with large 3 bladed props. The two bladed had virtually no drag when locked vertically. The three bladed props were for much bigger engines and were larger props. The two boats with three bladed props had slightly better 24 hour performance over 24 hours in near identical conditions than the two bladed. The best days run was 180 miles through the water with a mile or two difference for the other 3 bladed prop boat. The two bladed prop boat had a best days run of 176nm. Worse than the three bladed boats but not enough to notice.

If you can justify a feathering prop for better engine performance, have at it. Wouldn't expect any noticeable difference for sailing performance.

A while back checked on a feathering prop for my Pearson 35, similar underbody to a Bristol 39, and the only solution was to carve out a bit of the rudder to make the aperture bigger out of the rudder. Didn't seem like a big thing to do for anyone with minimal fiberglass skills. The cost/benifit equation luckily talked me out of it after more experience sailing the boat. The Bristol 39 seems to sail to its rating pretty well judging by its Bermuda Race corrected time victories.