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In this decade we are witnessing the transition from all metal to all composite helicopter rotor blades. One such helicopter is already in full scale production. A driving factor is structural reliability and guarantee against catastrophic failure. ...Low crack propagation rate and the nature of failures in composite structures are the characteristics which make this quality product superior to metal structures for rotor blades.

Manufacturing readiness of composite rotors and certification of flywheels depend in part on the maturity of nondestructive evaluation (NDE) technology for process optimization and quality assurance, respectively. ...Examples of possible occurring flaws or anomalies in composite rings as detected by NDE and validated by destructive metallography are shown. The general NDE approach to ensure quality of composite rotors and to help in the certification of flywheels is briefly outlined. ...The general NDE approach to ensure quality of composite rotors and to help in the certification of flywheels is briefly outlined.

Composite Propeller Blades have been developed and are now in production for the new generation of turbo-prop commuter aircraft. ...The method of manufacture utilises special tooling and a resin injection process specifically developed to produce composites with good fibre volume fractions and correspondingly high structural properties. Quality Control and NDT methods have been developed to ensure a high quality product, which involves the use of Ultrasonic, Radiographic and Vibrational Analysis. ...Certification of the Composite Propeller has necessitated rigorous structural and environmental testing of the finished blades, involving specialised rigs and techniques.

Composite materials are increasingly being used in the manufacturing of structural components in aeronautics industry. ...The successful implementation of a reliable quality assurance concept for adhesive bonding within manufacturing and in-service environments will provide the basis for increased use of lightweight composite materials for highly integrated aircraft structures thus minimizing rivet-based assembly. ...As a medium-scale European Consortium funded within the 7th Framework Programme, ENCOMB (Extended Non-Destructive Testing of Composite Bonds) brings together leading experts in aeronautics research and development providing advanced non-destructive testing methods for reliable quality assurance of adhesive bonds of CFRP structural components.

In relation to composite structures, this is being approached from several directions, two of which will be discussed. ...The approach most frequently used for inspection of composite parts is to pull the parts out of the manufacturing cells and route them to a centralized quality assurance area for inspection. ...Automated manufacturing processes, such as fiber placement, are now being used for manufacturing of large and/or complex composite parts. Automated processes open up opportunities to incorporate inspection into the manufacturing process, eliminating post-process inspection.

The selected guidance on technical topics related to this class of composites includes material selection, processing, characterization, testing, data reduction, design, analysis, quality control, application, case histories, and lessons learned of typical ceramic matrix composite materials. Volume 5, which covers ceramic matrix composites, supersedes MIL-HDBK-17-5 of June 17, 2002. ...CMH-17 provides information and guidance necessary to design and fabricate end items from composite materials. It includes properties of composite materials that meet specific data requirements as well as guidelines for design, analysis, material selection, manufacturing, quality control, and repair. ...The fifth volume of this six-volume compendium publishes technical guidance and properties on ceramic matrix composite material systems. The selected guidance on technical topics related to this class of composites includes material selection, processing, characterization, testing, data reduction, design, analysis, quality control, application, case histories, and lessons learned of typical ceramic matrix composite materials.

CMH-17 provides information and guidance necessary to design and fabricate end items from composite materials. It includes properties of composite materials that meet specific data requirements as well as guidelines for design, analysis, material selection, manufacturing, quality control, and repair. ...H") of the second volume of the CMH-17 compendium contains statistically-based data for polymer matrix composites that meets specific CMH-17 population sampling and data documentation requirements, covering material systems of general interest. ...Seventeen new data sets with complete documentation and publicly available specifications were added in the new Revision H of the Composites Materials Handbook, Vol.2. The new data sets include carbon fiber and glass fiber composites.

It is used by engineers worldwide in designing and fabricating products made from composite materials. The Composite Materials Handbook, referred to by industry groups as CMH-17, is a six-volume engineering reference tool that contains thousands of records of the latest test data for polymer matrix, metal matrix, ceramic matrix, and structural sandwich composites. ...CMH-17 provides information and guidance necessary to design, analyze, fabricate, certify and support end items using composite materials. It includes properties of composite materials that meet specific data requirements as well as guidelines for design, analysis, material selection, manufacturing, quality control, and repair. ...The first volume of this six-volume compendium contains guidelines for determining the properties of polymer matrix composite material systems and their constituents, as well as the properties of generic structural elements, including test planning, test matrices, sampling, conditioning, test procedure selection, data reporting, data reduction, statistical analysis, and other related topics.

Composite materials and structures are often avoided in general aviation vehicle applications because they are believed to be unnecessarily complex to design and analyze, and because manufacturing concerns often drive up cost and weight prior to component final delivery. ...This paper addresses two such applications of knowledge-based software systems for composite materials and structures, wherein embedded knowledge capturing proven engineering practice is concurrently applied to design, analysis and manufacturing concerns.

Additive Manufacturing of Aerospace Composite Structures: Fabrication and Reliability introduces the reader to the current state of technologies involved in processing and design of polymer-reinforced fiber composites using additive manufacturing's automated fiber placement methods, through ten seminal SAE International papers. ...Additive Manufacturing of Aerospace Composite Structures: Fabrication and Reliability introduces the reader to the current state of technologies involved in processing and design of polymer-reinforced fiber composites using additive manufacturing's automated fiber placement methods, through ten seminal SAE International papers. ...Additive Manufacturing of Aerospace Composite Structures: Fabrication and Reliability approaches the question of quality in these structures from a hands-on, solution-driven perspective.

Helicopter rotor systems are increasingly using flexible composite structures to provide the required control movement for the rotor blades. These structures such as rotor head flex beams can experience very high surface strains, which can be in the order of 15,000 με. ...Helicopter rotor hubs incorporating thick composite flexures are subjected to delamination failures with correlate to bending excursions.

Boron-epoxy composites are presently being utilized for primary aircraft structures. The basic joining technique for these materials of construction is adhesive bonding. ...This presentation briefly reviews the mechanical properties of adhesive-bonded composites, the techniques for manufacture, and the quality assurance necessary for acceptance of such structures.

Abstract Inspection of Composite panels is vital to the assessment of their ability to be fit for purpose. Conventional methods such as X-ray CT and Ultrasonic scanning can be used, however, these are often expensive and time consuming processes. ...In this paper we investigate the use of off-the-shelf Non-Destructive Test, NDT, equipment utilizing Fringe projection hardware and open source software to rapidly evaluate a series of composite panels. These results are then verified using destructive analysis of the panels to prove the reliability of the rapid NDT methods for use with carbon composite panels. ...These results are then verified using destructive analysis of the panels to prove the reliability of the rapid NDT methods for use with carbon composite panels. This process allows us to quickly identify regions of geometric intolerance or formed defects without the use of expensive sub-surface scanning systems, enabling a fast and cost effective initial part evaluation system.

Photon Induced Positron Annihilation and related technologies are currently being used to assess fatigue, thermal degradation, creep, and embrittlement in aircraft components composed of advanced composite and metal alloy materials from initial manufacture through failure, thereby providing a new reliability assessment tool for pre- and post-mission component evaluations and likelihood-of-failure assessments.

These structures are made of composite laminates, and they are flexible when folded and partially inflated. They contain light-activated resins, and can be cured with the sun light after being inflated in space.

As transport aircraft technology has progressed from subsonic to supersonic and now toward hypersonic applications, the demand for low-cost, lightweight, and high-strength materials for complex structural components has prompted the development of particulate-reinforced metal matrix composites (MMCs). Despite extensive room temperature evaluations of these MMCs, the toughness, creep, and welding properties of such materials when placed under high-temperature conditions have received little attention. ...In this paper, the effects of temperature on the tensile properties, fracture toughness, and related creep behaviors of a silicon carbide particulate reinforced 2124-T6 aluminum alloy matrix composite (SiCp/Al 2124-T6 MMC) are evaluated. To carry out this testing, variations in this material's mechanical properties, residual stresses and microstructure near welded joints and crack tips originating from machined notches were investigated.

Composites are finding more and more applications in the aircraft industry. Drilling good quality holes is a major challenge for the manufacturing industry.