[Public-List] Propellers

[Bart Knapp]

In the refit of our A30, it occurred to me that now would be as good a time
as any to upgrade the propeller.  This past summer I was on an Allmand 31
with a two bladed prop and in company with an Erickson 35 and Shannon 39.
We were on the ICW from Galveston to Corpus and initially had the wind
directly on the bow.  The Allmand had quite a task keeping up with the other
two.  I know that just by size of the boat, there would be a problem, but
with both the Erickson and Shannon throttling back, the Allmand had all it
could do to keep within about two miles of the others - that was under full
sail (after the wind had shifted) and the motor running.  The owner of the
Erickson said that by changing from a two bladed to three bladed prop, the
Allmand would have picked another knot or so.  The Allmand was pushing to
get 5 knots over ground with motor only and was just tipping 7 - 7.5 motor
sailing with a favorable wind direction and about a 30-35 degree heel.

 

Even though the A30 is currently land locked on a lake and effectively dry
docked because of the drought, if we get it to Galveston Bay, we will then
be able to get out to the Gulf of Mexico and the ICW.  I am looking toward
sailing on the bay and take an occasional trip on the ICW.  Those trips may
be in the company of other boats including the Erickson and Shannon, but
some others that are close to the same size as the A30 and going on up in
size.  Most of these cruises would be on conjunction with Sea Scout cruises
as was this summer's.  I came away from the cruise this summer with the
feeling that the Alberg would not be a good boat for the type of use we put
boats to on the summer cruise, but it is a case of a bird in the hand - an
A35 would be better, but..

 

Anyway, if I do change the prop out, what would be the size and pitch I
would need to be looking for.  Currently it would be married up to an A4.  

 

Any thoughts or ideas would be helpful.

 

Bart Knapp

 


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