Composite Wood and Plastic Propeller Blades 390153
MR. WEICK describes light-weight propeller blades constructed of wood and plastic by the Schwarz process, together with the materials and methods of construction. The blade, he explains, consists of a main core of laminated light wood which merges into a root of impregnated and compressed hard wood which, in turn, is threaded and screwed into a steel sleeve. The steel sleeve, he notes, can be mounted in either an adjustable or a controllable-pitch hub. The rest of the blade is described as being entirely covered with a heavy coating of reinforced plastic sheet, and the leading edge as protected with a flush strip of metal.
The author analyzes the problem of efficiency, particularly with regard to the effect of blade thickness and the drag of the root sections. He also deals with the matters of service record, flutter and vibration, ease of repair, and ice formation.