Regal 3300 Owner's Manual page 176

CHAPTER 6
Obtaining A Trimmed Position
Your vessel will reach a planing position at a specific speed. This speed
is determined by bottom design, weight distribution, water conditions,
and on board equipment. As the throttle is advanced the stern squats
and the bow rises initially. The trim tabs allow your boat to plane at a
slower speed than natural conditions allow.
In short bursts both trim tab rocker switches are pushed simultaneously
in the "bow down" position which causes the trim tabs to move down.
As the boat breaks over the bow high attitude the boat speed accelerates
and visibility increases.
If the boat is over-trimmed, it will plow the bow and the boat will lose
maneuverability. If this occurs, simply short burst the "bow up" trim
tab rocker switches simultaneously.
In the "learning curve" process, press the tab switches in half second
bursts. You will notice a slight delay from the time the switches are
pushed until the boat reacts depending on vessel speed. You will know
after awhile the optimum planing angle and speed.
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