Rudder design depth

[RichB]

I am repairing and fairing the stock rudder of my 1989 h- 23.
The current configuration has the entire blade portion below the waterline. And the rudder is 11" deeper than the keel.
The question is about the design depth. Looking from bottom to top the trailing edge is less than 1/2 " thick for the first 30". From there, it flares to 1 1/2". That flat surface creates drag as evidenced by the burbling.

Is this the proper configuration?

 

[Jackdaw]

Yes. The top foot or so of the rudder (past the 'kink') widens to strengthen it near the metal housing of the kick-up mechanism. Its not very efficient there hydrodynamically.

The rudder is deeper than the keel. Hence the kick-up.

 

[RichB]

Sailing the shallow and usually soft West side of Florida, I have enjoyed the additional depth of the rudder, giving notice to do a quick 180. Thanks for the information.

 

[rufus1138]

you could possibly add a fairing to soften the burbling and help hydro-dynamically, use high density west system and grind down to the glass on the flat part then build up a nice fair looking shape and re-gel coat. could be a neat experiment to find out if that will help with speed.

 

[Crazy Dave Condon]

If following advice to grind down to the glass, be extra cautious as the rudders are also foam filled for light but strong rudders as the glass is thin.