22 42 or the main motor 38 are operational that propellers 24 44 are protected from damage by unexpected rocks and the like which may hit the bottom of the boat when maneuvering boat 10 in any depth water any obstacles on the bottom of the water will contact the underside of afterplanes 30 50 and not propellers 24 44 further it should be noted that when main motor 38 is operational trolling motors 22 42 are not and also that afterplanes 30 50 function as conventional afterplanes or trim tabs in that they may rotate independently from one another thus as shown in fig6 afterplane 30 may be in an upward position while afterplane 50 may be in a downward position such a configuration is desirable for balancing boat 10 when its starboard side is weighted down fig7 shows propulsion apparatus 120 coupled to motorboat 110 in accordance with a second embodiment of the present invention in this embodiment a single afterplane 130 is coupled to stern 115 via a rotatable hinge 127 in contrast to the embodiment shown in fig5 trolling motor 122 having propeller 124 is now positioned in the center of 115 while main motors 138 148 are positioned on the starboard and port sides of the boat respectively this embodiment depicts the so called twin screw motorboat where both main motors 138 148 are operational during normal.