What is the purpose of trim tabs in an aircraft?

Trim tabs serve an essential function in an aircraft by helping to relieve control pressure and maintain flight attitude. When pilots adjust trim tabs, they can counteract the aerodynamic forces acting on the control surfaces, such as the ailerons and elevator. This allows the pilot to achieve a desired flight attitude without having to exert constant pressure on the controls, making it easier to fly and reducing pilot fatigue. By setting the trim appropriately, the aircraft can maintain level flight or a specific airspeed with minimal input from the pilot. This is particularly beneficial during long flights where sustained control pressure would otherwise be required.

While increasing speed, assisting with engine starting, and enhancing aerodynamic performance are important factors in aviation, they do not directly relate to the primary function of trim tabs. Trim tabs specifically focus on improving flight comfort and control efficiency by stabilizing the aircraft's attitude with less effort from the pilot.