1660Re: [AtkinBoats] Normand stern
- Sep 26, 2007I like the Normand stern on Shoals Runner, I think it will make the boat
behave like a double-ender in a following sea.
Shoals Runner also has a rudder that is better protected than the other
tunnel-stern boats with its steel shoe extending from the aft bottom of
the box keel past the end of the rudder then up onto the transom. This
should make backing this boat safer for the rudder than any of the
other tunnel-stern boats in the Atkin fleet.
But I'm not sure the Normand stern is used for the reason you
It is my understanding that a rudder on an inboard powered boat is never
turned more than 30 or 40 degrees or it will stall out because of the
high angle of attack, and then it will behave like a brake instead of a
rudder. When I look at the Tolman Seabright I'm building -- which
theoretically has the same keel, prop and rudder locations as Rescue
Minor -- it looks like the rudder would have to turn more than 70
degrees in order to divert water across the chines.
I think there must be another reason for the Normand stern. I have
always thought it was used as an elegant way to give the
boat "double-ender" performance without bending the aft sides toward
the center line.
> I think the reason Shoals Runner has the Normand stern is to get the--
> rudder out of the tunnel. On most of the other tunnel types the chine
> is high enough for the prop wash deflected by the rudder to go under
> it and out to the side. On Shoals Runner the low chine would block
> the flow from a rudder inboard of a square stern. The alternative
> would be an outboard rudder like on Sandpiper which also has low
> chines. Several people have said that they did not care for the
> Normand stern. They might need to think through any changes.
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