This paper presents the results of a parametric materials and weights study done by the author on a 26.4-foot diameter hinge- less composite rotor blade. The blade was studied using a variety of composite materials including S-glass, boron, graphite, and PRD-49(an organic fiber developed by the DuPont Company). It was used in conjunction with the lift/propulsion system of a study tilt wing aircraft having a design gross weight of 83,000 pounds.
The paper reviews the construction, materials and weights of the study blade and includes:
The impact of rotor weight on vehicle size and
weight.
• Blade geometry, cross section, construction, material description and structural properties, and the blade design criteria.

• A detailed weights analysis of the blade components comparing the weights of the various composite materials used in the study for the respective blades.

• A parametric study showing the variation in blade weights with blade radius, chord and disc loading.

An approach for predicting the weight of composite rotor blades in the early stages of preliminary design is presented and discussed. Data points include composite rotor blades designed and built at the Boeing Vertol Company.