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This document is to be used as a checklist by curriculum developers to create courses or training for critical composite repair, maintenance, and overhaul issues. This document will not take the place of courses or training requirements for specific job roles of a composite repair technician, inspector or engineer. ...This document will not take the place of courses or training requirements for specific job roles of a composite repair technician, inspector or engineer.

This paper discusses nondestructive testing (NDT) methods and techniques for detection of material and manufacturing anomalies in state-of-the-art graphite composites. Introduction of composites into large-scale production depends in large measure on the successful application of NDT for process control and monitoring. ...Visual, liquid-penetrant, radiographic, ultrasonic, sonic, thermal, and acoustic-emission NDT methods are used to evaluate graphite fiber composite aircraft specimens and structures. Reference standards are fabricated with built-in discontinuities, commensurate with each structural article fabricated. ...Tests were conducted on research and development graphite composite aircraft structures consisting of (1) molded graphite flap ribs, (2) graphite composite flap assembly, and (3) graphite composite horizontal stabilizer assembly.

The latest development in aircraft and aerospace structures is composite materials, which provide high strength, high stiffness, corrosion resistance, ease of fabrication, lower weight and eventual fuel savings. ...The strength/stiffness-to-weight ratio of composite materials has been proved higher than metals. Along with the development of materials, a very essential aspect is their maintenance and inspection. ...Only a few equipment are available at this time to enable effective inspection of composite material failures - delamination, disbonding, water ingestion, fiber fretting etc, which are quite different from metal failures.

Laboratory investigations of materials properties show that significant reductions in aero-engine weight and cost are possible by using fiberglass reinforced composite materials. These were first applied to fabrication of compressor blades by Rolls-Royce, Ltd. ...Since the conclusion of the research program coincided with a new design, in which the sole engine function was to support a VTO aircraft during transition, the composites were specified for low temperature components. This paper describes properties of such materials and explains the philosophy adopted in their application.

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.

In addition, it provides selected guidance on other technical topics related to this class of composites, including material selection, material specification, processing, characterization testing, data reduction, design, analysis, quality control, and repair of typical metal matrix composite materials. The Composite Materials Handbook, referred to by industry groups as CMH-17, is a six-volume engineering reference tool that contains over 1,000 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 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 fourth volume of this six-volume compendium includes properties on metal matrix composite material systems for which data meeting the specific requirements of the handbook are available.

The information provided is consistent with the guidance provided in Volume 1, and is an extensive compilation of the current knowledge and experiences of engineers and scientists from industry, government, and academia who are active in composites. The Composite Materials Handbook, referred to by industry groups as CMH-17, is a six-volume engineering reference tool that contains over 1,000 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 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 third volume of this six-volume compendium provides methodologies and lessons learned for the design, analysis, manufacture, and field support of fiber-reinforced, polymeric-matrix composite structures. It also provides guidance on material and process specifications and procedures for using the data that is presented in Volume 2.

Compressive load capacity of composite lattice structures are studied. The objective of this research is to investigate the buckling strength of composite lattice structures and to design the most weight efficient structure with the highest buckling load. ...The objective of this research is to investigate the buckling strength of composite lattice structures and to design the most weight efficient structure with the highest buckling load. ...Buckling strength of both the composite lattice cylindrical and conical shells under axial compressive loads are examined. The main emphasis is placed on the effects of geometric constraints and the optimal design of the structures.

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 last volume of this six-volume compendium is an update to the cancelled Military Handbook 23, which was prepared for use in the design of structural sandwich polymer composites, primarily for flight vehicles. The information presented includes test methods, material properties, design and analysis techniques, fabrication methods, quality control and inspection procedures, and repair techniques for sandwich structures in military and commercial vehicles. ...The information presented includes test methods, material properties, design and analysis techniques, fabrication methods, quality control and inspection procedures, and repair techniques for sandwich structures in military and commercial vehicles. The Composite Materials Handbook, referred to by industry groups as CMH-17, is a six-volume engineering reference tool that contains over 1,000 records of the latest test data for polymer matrix, metal matrix, ceramic matrix, and structural sandwich composites.

Due to the low analysis time requirements, the software package is an efficient tool for use in design and optimization cycle of bolted joints involving composite materials. This work is conducted as part of a larger effort currently underway at the AdTech Systems Research, Inc. to establish a baseline to extend the joint design methodology for generalized composite systems including life prediction, thermal effects and dissimilar materials. ...This work is conducted as part of a larger effort currently underway at the AdTech Systems Research, Inc. to establish a baseline to extend the joint design methodology for generalized composite systems including life prediction, thermal effects and dissimilar materials.

An extensive secondary fabrication program was conducted in aluminum-boron composite material under both contract and independent research and development funding. Forming, joining, and machining of diffusion-bonded sheet material was investigated during the fabrication and final assembly of a fullsized missile payload adapter. ...Machining of composites was done with diamond tools. Chipless methods proved satisfactory with such processes as electrodischarge and ultrasonic machining. ...Mechanical tests proved the high strength of the composite shapes. Recent investigations include methods of increasing transverse strength such as stainless steel wire, titanium-backed tape, and heat treatment of matrix.

One of the most promising directions is products manufacturing from composite materials. The technology of composite micro-powders production on the basis of heat-resistant nickel alloy EP648 and Al2O3 is proposed. ...The aim of this research is to develop a method of producing composite micropowders for additive technology application. This method is based on modification of the metal micropowders surface by the second phase in a planetary mixer (mechanochemical synthesis).The obtained composite micropowders are compared with powders which are recommended for selective laser melting usage (produced by MTT Technology). ...This method is based on modification of the metal micropowders surface by the second phase in a planetary mixer (mechanochemical synthesis).The obtained composite micropowders are compared with powders which are recommended for selective laser melting usage (produced by MTT Technology).

The faculty and staff of the Raspet Flight Research Laboratory (RFRL) have concluded a project with an industrial customer to lead a group of engineers and technicians in a study of the “art” of developing a prototype composite aircraft. The objective was to produce a turbine powered, composite, pressurized, single-engine aircraft, which would introduce the team to the many aspects of a complex aircraft in a environment. ...It was proposed that the A-36 structure be replaced with composite structures in three steps of increasing complexity. The sequence was to first design-build-test-fly the tail, then the wings, and finally the fuselage. ...To limit the difficulty of the project development and to allow a meaningful comparison between aluminum and composite structures, the configuration modifications were to be minor and to utilize existing RFRL Marvel II composite technology.

In this research graphite/honeycomb composite material and aluminum sheet metal has been used. The results show that drill geometry, speed and feed rate have substantial effects on the hole quality and also there was gradual variation of the thrust and lateral forces with feed rates.

UAS structures need both the introduction of new advanced composites and the definition of light weight construction based on thin walled configuration. With this idea in mind, Stiffening concepts are frequently used to increase structural performance, i.e. buckling characteristics, of a thin plates. ...Manufacturing of composite stiffened structures can give rise to the presence specific damaged situations such as skin/stiffener de-bonding. ...The static structural behavior of a damaged stiffened composite panel is summarized from previous research investigation and presented. Uniaxial compression and biaxial test loading conditions are applied to the panel in order to point out the damage effects on static behavior.

Due to the conventional autoclaving of pre-impregnated materials causes high costs in the production of carbon fibre structures, new injection methods have become more and more relevant. The research project “CFK-Tex” focuses on the automated handling and processing of preforms out of dry carbon fibre textiles. Regarding the advantages in quality improvement and process time, an automation of all process steps is getting enforced. The major challenge, in addition to the difficult handling-properties of the materials and high quality demands, is the enormous variety of outline variants caused by small production quantities but many different textile cuts per part. In the first step the requirements of an automated system are exactly analyzed considering the specific material properties as well as process and product based characteristics.

Nowadays LHP (CPL) is widely used in thermal control systems for space and ground applications. Wick structure is a key element which plays at least two roles: capillary pump to move a working fluid from condenser to the heat loaded zone and thermal and hydraulic breaker between liquid and vapor in LHP (CPL). This paper is devoted to the R&D of LHP with advanced low-cost ceramic wick structure, which has a high capillary pressure head and low thermal conductivity. First set of tests with acetone as a working fluid was done in Porous Media Laboratory, Minsk, Belarus to prove the possibility to use such kind of wick in present and future designs of LHP (CPL).

The report presents some findings of comprehensive research and development works being carried out in UkrRIAT and aimed to creating efficient methods and means of high endurance connection of the commercial aircraft airframe components.

The collaborative development of digital twins will inform additive manufacturing (also known as 3D printing), advanced composites, assembly, and industry 4.0 processes at GKN Aerospace's Global Technology Centre in order to enable the high rate production of aircraft structures.