Hull tracking

[Archive]

I have a 19' aluminium runabout. The hull is a Dave Jackman design.The boat tends to track poorly in a trailing sea, but not to the point of broaching. I have been looking at welding short strakes to the hull similar to that of the Stessel Blue Water 5.5 hull. Any comments regarding this before I proceed would be appreciated.

[Archive]

A small keelson, strake, of fin well aft can help, as can moving weight aft slightly. Your strake does not need to be particularly long, it just needs to be at the back of the boat. Though I don't have any science to back this up, I like, as a general rule of thumb, to have the CLR (the center of underwater profile area including rudder or outdrive) at or aft of the LCF (the center of the waterplane).

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Stephen Ditmore
New York

[Archive]

A recent article on waterjets (in Professional Boatbuilder) discussed the installation of small fins at the transom of a hull designed for conventional screw propulsion (with rudder) that developed tracking problems with the removal of rudder etc, and installation of the jet. The placement of the small fins greatly improved the tracking of the boat.