Outboards and stern drive propulsion are used on a wide variety of craft these days and most of then have power trim installed. This is used to adjust the angle of the drive leg as the boat comes onto the plane so that the thrust from the propeller remains close to horizontal to give maximum efficiency.
The control for the power trim is usually a switch incorporated into the throttle lever but now Mercury has introduced an automatic system that adjust the power trim to match the conditions, making the driving of boats that much easier.
This new Mercury system can be specified for all of their larger outboards and stern drives. GPS and motion sensors in the control box can measure the speed and any change of heading and this sends signals to the control to automatically adjust the angle of the drive leg. The system allows the timing and the adjustment to be tailored to the requirements and performance of individual boats which is done during the set-up process.
This means that as the boat comes onto the plane the drive leg is automatically trimmed out to match the change of trim of the hull. If the sensors determine that the sea conditions are lively then the drive is trimmed in accordingly and the same applies when the boat is turning. At low speeds the drive is trimmed right in again so the whole process is fully automatic allowing the driver to focus on controlling the boat.
By Dag Pike
