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July 2013 www.sname.org/sname/mt (in review) REVIEWED BY DAVID A. BRESLIN Some of us can remember back to a time when reliability was always of utmost importance when making decisions on which product to buy. Smart buyers wanted to avoid buying products that could be impolitely, if not accurately, referred to as junk.? ankfully times have changed in many indus- tries such as consumer electronics, and often, reliability now can be taken for granted. But thats not necessarily the case in all industries, which is why books such as Practical Reliability Engineering are so extraordinarily valuable. What is reliability? Simply stated, it is the probability that an item will perform a required function without failure under stated con- ditions for a stated period of time. Reliability is important. After all, a product with poor reliability can have undesirable consequences. Owners and operators of unreliable products are left to contend with unanticipated maintenance and repair costs, harmful interruptions to operations, premature replacement costs, and perhaps the possibility of injury or death of innocent workers and bystanders. And for designers and manufacturers, the consequences include higher war- ranty costs, legal liability, damage to brand image, and the departure of once-loyal customers. So the concept of reliability is simple, and the benets of high reliability are apparent. But engineering products that will be reliable in service can be complicated. is is especially true for products that economists classify as durable goods?prod- ucts that have useful lives of three years or more. After all, how does one determine the probability that a new product will perform as required given the variability inherent in material properties, manufacturing processes, product use, and user knowledge? And if it is determined that the probability will not meet user requirements, then what is the best strategy for reen- gineering the product to improve its reliability without unduly aecting cost, size, weight, and schedule? Fortunately, the answers can be found within the pages of this book. e authors begin by carefully laying out the principles of reliability engineering, starting o with a review of the applicable theories of probability and statistics, which are fundamental to the eective application of reliability engineering. e authors then Practical Reliability Engineering, Fifth Edition By Patrick D. T. OConnor and Andre Kleyner PUBLISHED BY JOHN WILEY & SONS, LTD. Modeling Ships and Space Craft: the Science and Art of Mastering the Oceans and Skies By Gina Hagler PUBLISHED BY SPRINGER SCIENCE AND BUSINESS MEDIA, LLC REVIEWED BY CARL DELO This book is part of the publishers phys- ics catalog, and is intended for a general audience. However, the central topic of the book, modeling vessels, is treated in the context of the history of technology. Part III, which covers the advent of systematic scale model test- ing in modern hydro and aerodynamics, focuses primarily on the formative work of William Froude, David Taylor, and the Wright brothers. e evolu- tion of scale model testing in place of full-sized prototypes is described in some detail. e nancial pressures that rst spurred scale model testing of ships, and the struggles of Froude and Taylor to institute rigorous and comprehensive hydraulic testing programs to support and advance the burgeoning maritime industry, is engaging. By comparison, the small-scale investigations of the Wright brothers in the new eld of aeronautics become all the more impressive in comparison. It is truly remark- able that two men working systematically and doggedly could exert as much inuence on the modern world as the large government research eorts that Froude and Taylor eventually commanded. ese chapters on the early modelers contain interesting historical photographs, laboratory schematics, and machine drawings. ere is not much discussion of the gures, however, so they are useful primarily to those who are experienced at interpreting such drawings. e end of part III contains a sec- tion on rocketry (not space craft, as the title suggests), also from a historical viewpoint. As in the prior chapters, the underly- ing physics of the model testing is a secondary issue. In some cases, important concepts are glossed over or incomplete. is treatment is not a serious drawback in the framework of the nar- rative, as a reader interested in the engineering details of model testing will likely move on to more advanced texts. e book becomes problematic once it strays from its central topic. Part I of the book deals with airborne and aquatic animals. Unfortunately, there are numerous examples of misinterpre- tations of basic physical principles, omissions of important concepts, and outright errors of fact in the explanations of how animals y or swim. Part II covers the evolution of hydrody- namic and aerodynamic theory, but contains misstatements of the Bernoulli Equation, Newtons Laws of Motion, the causes of lift and drag, the source of the Magnus eect, and more. The glossary of technical terms also is rife with errors. Readers are advised to look elsewhere for insight into these top- ics and to consider this a work of history rather than physics. MT Carl Delo, PhD, is a SNAME member and associate professor of mechanical engineering at SUNY Maritime College, where he is currently developing a new hydrodynamics laboratory.