Abstract: An expandable shaft of the slotted type made of metal and a fiber and resin composite material. The shaft is formed of an elongated shell having hollow portions filled with a fiber/resin material.

Abstract: An adjustable mounting arrangement for mounting magnetic heads used for the recording and playback of information on magnetic tape. Vertical and azimuth adjustment utilizing a simple bracket facilitate optimization of head location.

Abstract: A phonograph pickup arm for use in disc records arranged to compensate for error in the tracking path. By use of adjacent curved surfaces in mounting and support members the point of rotational access of the pickup arm shifts as the stylus associated with the pickup arm moves left to right or vice versa to compensate for the usually present tracking error.

Abstract: An angle of attack indicating device for use in indicating the sail trim of a sail boat or the angle of attack of an airfoil in order that the sail or the airfoil may be optimized. The device of the present invention employs wind operated sensing vanes coupled to associated indicator vanes mounted on either side of the leading edge of an airfoil such as a sail or wing, which are employed to sense the airflow differential on the opposite sides of the airfoil. By visual indication of the relative positions of the wind responsive vane and the indicating vane appropriate adjustment may be made to maintain the proper attack angle.