COMPOSITE STRUCTURE AND TECHNOLOGY OF ULTRA LIGHT UAV MODEL

One of the basic preconditions of successful realization of the project ultra light UAV [1-3] is the choice of modern constructional materials and a substantiation of the optimum design decisions allowing the most full to use their property. Therefore at creation of model ultra light UAV a lot of efforts has been given to development of requirements to properties and structure of the primary structural elements of an airframe and ways of their practical realization. Research and development on this problem were carried out on an example of a wing, as one of the most loaded components of a structure of the aircraft. For a wing the contradiction between aerodynamic requirements, on the one hand, and also strength and rigidity of a design, with another is especially sharp. The effective decision of this problem at a modern level of development of techniques and technology can be carried out by wide application of composite materials. Therefore the experimental model ultra light UAV practically on 95 % has been made of composite materials. Sandwich structural elements were the basic types at creation of panels of a wing. Face layers of panels were manufactured as a layered composite carbon/epoxy laminate. Aramid honeycomb is used for a core layer. Balance of assembly of the panel assumed formation in a matrix of 1 outer face layer of the panel, gluing of a honeycomb and, then, formation of an inner face layer. The structure of face layers, their thickness, the sizes of a core layer are the parameters which are a subject optimization by criterion of weight of a wing in conditions geometrical, strength and stiffness of restrictions. The general approach to the decision of this problem and some results are a subject of the separate report. Use of sandwich panels has allowed to refuse from stringer reinforcement that has positively affected simplicity and adaptability to manufacture of a structure and promoted decrease in weight of a wing. The important structural element of a wing is the main beam 3 (Fig.l). Its design and manufacturing techniques are very simple. The flanges of a beam of variable cross-section section of the carbon fabric are pasted in the panel during its manufacturing. The thick vertical wall also represents sandwich with a foam core and carbon/epoxy face layers