What are trim tabs and what do they do?

Trim tabs are movable metal tabs of various sizes that extend beyond the edge of the hull bottom at the transom.  Adjusting their position up or down can help to level the boat in changing sea conditions and loads and “fine-tune” the ride, resulting in improved control of the vessel for the skipper and a more comfortable experience for everyone onboard.  

A quality trim tab system will also enhance overall boat performance and increase fuel efficiency.  It does this by helping the operator achieve the vessel’s optimum running angle — the specific configuration where ride and engine performance are optimized.  Since it is a dynamic system that can be adjusted “on the fly” for changing conditions — changes in weight load and distribution, wind/wave angle, running up or down swell, etc. — trim tabs can keep a boat performing at peak efficiency in any situation.

Here are some additional key benefits to Trim Tab use:

a) Get out of the hole and onto plane faster.  A boat that gets on plane quickly is more efficient and more effective for water sports, shallow water fishing and other activities.

b) Stop boats from “porpoising.”  The bow of a poorly trimmed boat can rhythmically rise and fall (like a porpoise jumping and falling below the surface).  Trim tabs can be used to eliminate this uncomfortable and inefficient hull behavior.

c) Stay on plane at lower speeds.  A boat’s ability to remain on plane when speed is reduced makes it more efficient, more comfortable, and easier to control. 

d) Reduce listing. This is the side-to-side roll/tilting of the vessel due to propeller torque and/or uneven weight distribution.  Adjusting the trim tabs can eliminate this, even as people move and weight is shifted around the vessel.