This book is an attempt to present under one cover the current state of knowledge concerning the potential lightning effects on aircraft and that means that are available to designers and operators to protect against these effects. The impetus for writing this book springs from two sources- the increased use of nonmetallic materials in the structure of aircraft and the constant trend toward using electronic equipment to handle flight-critical control and navigation function.
Lightning Physics and Lightning Protection presents a comprehensive and up-to-date review of lightning, including its hazards and protection techniques. The authors first discuss the effectiveness of conventional protective measures, supply technical advice and practical recommendations, and explore the prospects for the preventive control of a lightning leader, followed by a discussion of the initiation of a leader and return stroke and subsequent components. After including measurements useful for understanding lightning and its effects, the book describes the mechanism of lightning discharge processes. It then examines the effects of large aircraft, high-voltage lines, and other high-altitude constructions on lightning trajectory and leader attraction. The book concludes by studying the action of lightning's electrical and magnetic fields and the lightning current on industrial premises, power transmission lines, underground communications, aircraft and their electrical circuits, and the induction of a dangerous overvoltage. A clear, straightforward, and systematic presentation of complicated material, Lightning Physics and Lightning Protection provides deep insight into the physics of lightning, simple analytical estimates, and a detailed illustration of effects by computer simulation, making this resource essential for those who investigate lightning phenomena and who have to solve practical protection problems.
Lightning protection for fighter aircraft is presently based on the requirements of MIL-B-5087 and refined by the recently issued MIL-STD-1757. These documents specify current and energy levels sufficient to cover greater than 99 percent of the cloud-to-ground strikes. These levels are applied to aircraft according to lightning strike zones established by attach point analysis and test. The application of these specifications to aircraft is made without consideration of mission, probability of strike occurrence, or penalties associated with protective designs. Data from recent in-flight test programs, a tabulation of aircraft strike rate per aircraft type, and an examination of strike damage records, all show that the requirements may be too stringent and that a revision to the method of applying lightning specifications to aircraft may be justified. In conventional and V/STOL high-technology fighter aircraft, weight has a direct effect upon performance, combat effectiveness, losses, and life-cycle cost. Unnecessarily stringent lightning protection requirements can add weight out of proportion to the lightning risk. A systematic method of tailoring requirements to risk or damage probability is desirable to provide a more balanced protective design. This paper presents a probabilistic approach to the design of aircraft lightning protection which may be a useful method of avoiding conventional worst case design penalties. (Author).
This book gives a contemporary and comprehensive overview of the physics of lightning and protection systems, based on nearly 40 years of research, teaching, and consultancy work in this area. The book begins with an overview of the climatology of lightning and electric storms, as well as giving insight into lightning discharge from the preliminary discharges or processes such as corona, stepped leader, and subsequent return strokes, including the important submicrosecond threats and continuous current. The subsequent chapters present measures of lightning threat analysis to aircraft and electric power systems, protection measures to be used in high-voltage to low-voltage computer and communication systems, as well as to commercial and domestic buildings. The book discusses challenges posed by the submicrosecond lighting current changes and climate change to present and future high-voltage apparatus and structures (including carbon composite aircraft and new buildings) exposed to lightning strikes. Including worked examples, illustrations, and detailed analysis, Lightening Engineering will be of interest to electrical engineers, as well as researchers and graduate students.
