A boat includes at least three trim devices positioned aft of the boat's transom. To improve the boat's ability to get on place, each trim device is initially positioned to a deployed position. The speed of the boat is then determined as the boat gains speed. When the speed of the boat exceeds a first predetermined threshold, the first trim device is moved from the deployed position to a non-deployed position. When the speed of the boat exceeds a second predetermined threshold, the second trim device is moved from the deployed position to a non-deployed position. When the speed of the boat exceeds a third predetermined threshold, the third trim device is moved from the deployed position to a non-deployed position. At least one of the first, second, and third predetermined thresholds is different from the other two of the first, second, and third predetermined thresholds.

A boat includes at least three trim devices positioned aft of the boat's transom. To improve the boat's ability to get on place, each trim device is initially positioned to a deployed position. The speed of the boat is then determined as the boat gains speed. When the speed of the boat exceeds a first predetermined threshold, the first trim device is moved from the deployed position to a non-deployed position. When the speed of the boat exceeds a second predetermined threshold, the second trim device is moved from the deployed position to a non-deployed position. When the speed of the boat exceeds a third predetermined threshold, the third trim device is moved from the deployed position to a non-deployed position. At least one of the first, second, and third predetermined thresholds is different from the other two of the first, second, and third predetermined thresholds.

An actuator comprises a housing and a drive tube assembly disposed within the housing. The drive tube assembly includes a drive tube provided with internal threads, a piston nut provided with external threads which threadedly engage the inner threads of the drive tube, and an output shaft connected to the piston nut. A motor rotates the drive tube to cause the piston nut to reciprocate along a length of the drive tube and the output shaft to reciprocate relative to the housing. There are bearings which transmit axial loads from the drive tube to the housing and transmit radial loads from the drive tube to the housing.

An actuator comprises a housing and a drive tube assembly disposed within the housing. The drive tube assembly includes a drive tube provided with internal threads, a piston nut provided with external threads which threadedly engage the inner threads of the drive tube, and an output shaft connected to the piston nut. A motor rotates the drive tube to cause the piston nut to reciprocate along a length of the drive tube and the output shaft to reciprocate relative to the housing. There are bearings which transmit axial loads from the drive tube to the housing and transmit radial loads from the drive tube to the housing.

A wakeboat creates a wake, the performance level of the wake varying depending upon the mass of the wakeboat, the wakeboat including a hull; an engine supported by the hull; a controller supported by the hull; a processor coupled to the controller; a memory coupled to the processor; a sensor configured to measure at least one parameter of the wakeboat, the controller being coupled to the sensor and being configured to receive data from the sensor, the controller being configured to derive the present mass of the wakeboat from said sensor data, the controller being configured to determine the present wake performance level of the wakeboat based on the present mass of the wakeboat; and a display coupled to the controller, the controller being configured to use the display to indicate the present wake performance level of the wakeboat.

A wakeboat creates a wake, the performance level of the wake varying depending upon the mass of the wakeboat, the wakeboat including a hull; an engine supported by the hull; a controller supported by the hull; a processor coupled to the controller; a memory coupled to the processor; a sensor configured to measure at least one parameter of the wakeboat, the controller being coupled to the sensor and being configured to receive data from the sensor, the controller being configured to derive the present mass of the wakeboat from said sensor data, the controller being configured to determine the present wake performance level of the wakeboat based on the present mass of the wakeboat; and a display coupled to the controller, the controller being configured to use the display to indicate the present wake performance level of the wakeboat.

A watercraft is provided with fin on its transom. The fin extends outwardly from a portion of the transom that extends into the water. The fin includes a first portion and a second portion positioned rearwardly of the first portion. The second portion is inclined downwardly and rearwardly relative to the first portion and positioned so as to provide lift and to channel water toward the propeller. The watercraft may be a pontoon boat having first and second laterally-spaced pontoons located under the deck on opposite sides of the transom. Additional fins may be mounted on the first and second laterally-spaced pontoons.

A watercraft is provided with fin on its transom. The fin extends outwardly from a portion of the transom that extends into the water. The fin includes a first portion and a second portion positioned rearwardly of the first portion. The second portion is inclined downwardly and rearwardly relative to the first portion and positioned so as to provide lift and to channel water toward the propeller. The watercraft may be a pontoon boat having first and second laterally-spaced pontoons located under the deck on opposite sides of the transom. Additional fins may be mounted on the first and second laterally-spaced pontoons.

A tile assembly (22) which, in use, is fitted to a base structure to form at least part of a fluid washed surface. The tile assembly comprises a housing (42) with at least one plenum (45) being provided within the housing (42). A wall (44) of the housing (42) is provided with a plurality of flow passages (46) which extend from the plenum side of the wall (44) to an outer surface (48) of the wall. Flow passage closures (50) are provided which are operable to open and close at least some of the flow passages (46).

A tile assembly (22) which, in use, is fitted to a base structure to form at least part of a fluid washed surface. The tile assembly comprises a housing (42) with at least one plenum (45) being provided within the housing (42). A wall (44) of the housing (42) is provided with a plurality of flow passages (46) which extend from the plenum side of the wall (44) to an outer surface (48) of the wall. Flow passage closures (50) are provided which are operable to open and close at least some of the flow passages (46).