Abstract: A drive system includes an electric motor having a rotor and a stator. A nut is rigidly connected to the rotor. A spindle is positioned to be non-rotating and has a drive connection with the nut. A piston rod has one longitudinal end fixed to the spindle, with the spindle extending coaxial to the piston rod. The spindle is driven by the nut in response to rotation of the rotor so that the piston rod executes a linear movement controlled by the electric motor.

Abstract: A static trimmer for a hovercraft is provided for shifting the center of buoyancy of an air-cushion of the hovercraft in relation to the center of gravity. The static trimmer includes a peripheral elastic skirt (2) having a plurality of skirt segments (5) each having a back skirt (3) and a finger skirt (4). The peripheral elastic skirt (2) further includes at least four independent lateral sections (6, 7, 8, 9) which can be moved in an inward or outward direction independently of each other. The static trimmer further includes at least two tension cables (15, 16) disposed in each independent lateral section (6, 7, 8, 9) for moving each finger skirt (4) of each of the plurality of skirt segments (5). Each of the tension cables (15, 16) further include a first partial tension cable and a second partial tension cable.