Most of the larger boats that come into our marina for service have trim tabs. If you don’t have them on your boat, it would behoove you to find out why many manufacturers are installing them as options or even standard equipment.
There is no mystery to a set of trim tabs. They get the boat out of the hole and on plane quickly, they correct for uneven weight distribution, improve speed, safety, and overall boat performance. The benefits are many-fold. They improve fuel efficiency, visibility, wake size and boat handling in general.
How they work
Trim tabs usually consist of two adjustable stainless steel planes mounted at the transom of the boat. Controlled by a hydraulic power unit, the tabs can move up and down when activated by the boater.
Think ailerons and elevators on an airplane. Trim tabs do much the same thing for a boat. They provide lift in order to compensate for changes in speed, weight distribution, and water conditions. When they are deflected downward, the water force on the trim tab creates upward pressure, raising the stern and reducing hull resistance. The surface area of the tab, the angle of deflection, and the speed of the boat all contribute to greater lift.
When planning an installation, you need to make sure that the tabs are big enough. Figure on an inch of tab size for every foot of boat for maximum control – ie: a 42′ boat would work best with 42″ tabs. Sometimes there is just not enough room for the optimal size – in that case use the biggest size that will fit and it should do an acceptable job.
As with any equipment, you will get the hang of controlling the system very easily, but you can enhance the performance with add-ons such as Automatic Tab Retractors, Trim Indicators and Automatic Trim Tab controls. If you already have trim tabs, we could add any of these enhancements for you or perform trim tab repairs for your boat.