The availability of efficient and cost-effective technologies to repair or extend the life of aging military airframes is becoming a critical requirement in most countries around the world, as new aircraft becoming prohibitively expensive and defence budgets shrink. To a lesser extent a similar situation is arising with civil aircraft, with falling revenues and the high cost of replacement aircraft.This book looks at repair/reinforcement technology, which is based on the use of adhesively bonded fibre composite patches or doublers and can provide cost-effective life extension in many situations. From the scientific and engineering viewpoint, whilst simple in concept, this technology can be quite challenging particularly when used to repair primary structure. This is due to it being based on interrelated inputs from the fields of aircraft design, solid mechanics, fibre composites, structural adhesive bonding, fracture mechanics and metal fatigue. The technologies of non-destructive inspection (NDI) and, more recently smart materials, are also included. Operational issues are equally critical, including airworthiness certification, application technology (including health and safety issues), and training.Including contributions from leading experts in Canada, UK, USA and Australia, this book discusses most of these issues and the latest developments. Most importantly, it contains real histories of application of this technology to both military and civil aircraft.

The conventional approach to through-life-support for aircraft structures can be divided into the following phases: (i) detection of defects, (ii) diagnosis of their nature and significance, (iii) forecasting future behaviour-prognosis, and (iv) pre scription and implementation of remedial measures including repairs. Considerable scientific effort has been devoted to developing the science and technology base for the first three phases. Of particular note is the development of fracture mechanics as a major analytical tool for metals, for predicting residual strength in the presence of cracks ( damage tolerance) and rate of crack propagation under service loading. Intensive effort is currently being devoted to developing similar approaches for fibre composite structures, particularly to assess damage tolerance and durability in the presence of delamination damage. Until recently there has been no major attempt to develop a science and tech nology base for the last phase, particularly with respect to the development of repairs. Approaches are required which will allow assessment of the type and magnitude of defects amenable to repair and the influence of the repair on the stress intensity factor (or some related parameter). Approaches are also required for the development and design of optimum repairs and for assessment of their durability.

Aircraft Sustainment and Repair is a one-stop-shop for practitioners and researchers in the field of aircraft sustainment, adhesively bonded aircraft joints, bonded composites repairs, and the application of cold spray to military and civil aircraft. Outlining the state-of-the-art in aircraft sustainment, this book covers the use of quantitative fractography to determine the in-service crack length versus flight hours curve, the effect of intergranular cracking on structural integrity and the structural significance of corrosion. The book additionally illustrates the potential of composite repairs and SPD applications to metallic airframes. - Covers corrosion damage assessment and management in aircraft structures - Includes a key chapter on U.S. developments in the emerging field of supersonic particle deposition (SPD) - Shows how to design and assess the potential benefits of both bonded composite repairs and SPD repairs to metallic aircraft structures to meet the damage tolerance requirements inherent in FAA ac 20-107b and the U.S. Joint Services

Provides repair methods for adhesive bonded and composite structures; identifies suitable materials and equipment for repairs; describes damage evaluation criteria and techniques, and methods of inspection before and after repair.

Bonded composite repairs are efficient and cost effective means of repairing cracks and corrosion grind-out cavity in metallic structures, and composite structures sustained impact and ballistic damages, especially in aircraft structures. This book grew out of the recent research conducted at the Boeing Company and the Defence Science and Technology Organisation (DSTO, Australia) over the past ten years. Consequently it is predominately a compilation of the work by the authors and their colleagues at these two organizations on the design and analysis of composite repairs. Composite Repair is entirely devoted to the design and analysis of bonded repairs, focusing on the mathematical techniques and analysis approaches that are critical to the successful implementation of bonded repairs. The topics addressed are presentated in a sufficiently self-explanatory manner, and serve as a state-of-the-art reference guide to engineers, scientists, researchers and practitioners interested in the underpinning design methodology and the modelling of composite repairs. - The only book devoted entirely to the design and analysis of bonded repairs - Focusing on mathematical techniques and analytical methodologies that are critical to the successful implementation of bonded repair - A companion reference book to the United Stated Air Force (USAF) bonded repair guidelines (Guidelines for Composite Repair of Metallic Structures-CRMS, AFRL-WP-TR-1998-4113) and the Royal Australian Air Force (RAAF) Design Standard DEF(AUST)995 - Covering a variety of topics and effects: repairs of fatigue and sonic fatigue cracks, and corrosion grind-out cavity, and effects of secondary bending, octagon-shaped patches, thermal residual stresses, patches in proximity, patch tapering edge, etc.

The major objective of this book was to identify issues related to the introduction of new materials and the effects that advanced materials will have on the durability and technical risk of future civil aircraft throughout their service life. The committee investigated the new materials and structural concepts that are likely to be incorporated into next generation commercial aircraft and the factors influencing application decisions. Based on these predictions, the committee attempted to identify the design, characterization, monitoring, and maintenance issues that are critical for the introduction of advanced materials and structural concepts into future aircraft.