scope:

The purpose of this handbook is (1) to provide a standardized basis, acceptable to the Air Force, the Navy, the Army and the Federal Aviation Administration, for the design and construction of fiber reinforced plastic composites primarily for use in aerospace vehicles; (2) to provide appropriate data on the mechanical properties of such composites; and (3) to provide design techniques and analytical procedures which account for anistropy of these composites and permit computation of directional properties. These design techniques are provided for guideline purposes, and shall not be construed as requirements unless specifically identified in a contract.

The mechanical properties contained herein have been developed, as a cooperative effort of government and industry, for laminates made from commonly used material systems and fabricated by processes representative of current industrial practice. The bulk of the data pertains to fiberglass composites, principally of E glass. Additional data is provided for S glass composites and for boron reinforced composites. As data becomes available, further information, on existing materials, as well as newer materials, will be included in revision to the handbook.

Information on the constituent materials which form the composite and descriptions of pertinent fabrication processes are also included.

A chapter on the design and analysis of composites is provided. It furnishes the expressions for computing the strength and elastic relations of laminates based on monolayer properties, as well as procedures and information for the alteration or optimization of the design of simple composite structural elements.

The fastening and joining of composite parts to each other and to metallic parts is an essential feature in composite design. A chapter on fastening and joining is therefore included.

Other chapters are of a more general nature, and by reference to other documents, cover the topics of repair quality control and nondestructive testing.

The handbook values normally must be reduced as appropriate for specific applications to account for the effects of operational environmental conditions, including but not limited to the cumulative effects of temperature, humidity and cyclic loading. The mechanical properties presented for the various types of laminates are not intended to represent design allowables. Generally, they are most useful for preliminary design purposes. Property data is provided over the normal temperature range from −65F to 160F and beyond the maximum intended use temperature for high service temperature materials. In addition the effects of exposure to one-hundred percent relative humidity atmospheres are shown. Such data is intended as an aid in assigning property values to a material. In specific cases where it is necessary or preferred to develop strength properties superior to those in the handbook, acceptance of such values must be obtained from the procuring or certifying agency. The applicability and interpretation of specific provisions of the handbook will also be defined by the procuring, regulatory or certifying agency