Document Type: Book (Technical Reference) Purpose: Informational Authority: Author Expertise

Series: First in the planned "Airplane Engine Design Series."

Scope: Written by Glenn D. Angle, "Consulting Engineer; formerly In Charge of the Design of Airplane Engines for the United States Army Air Service."

(from the Preface): "The airplane engine has apparently received an equitable share of attention among technical writers when we consider the numerous other special forms of the internal combustion engine, particularly as to the comparative size of the industry or to the actual number of each type in use. It is in all probability due to the exacting requirements and to the highly interesting structural features of the airplane engine that the various subjects pertaining to its design and construction have been so voluminously treated; and yet, among all these volumes, it is a regrettable fact that there is hardly a one really conspicuous in having been prepared especially for the designer. No prolix explanations are necessary to emphasize the need for such books, nor to further justify the present work, if one can but appreciate the basic importance of design data which is founded upon sound theory and actual practice. Perhaps the main reason that books of this nature have not appeared heretofore is, that those sufficiently experienced to undertake their preparation did not feel the task to be warranted during the course of such rapid experimental progress.

Although the design of airplane engines had its greatest impetus during the late world conflict, the more scientific developments have occurred since, and there is now a vast amount of data and experience available which should guide future developments along more constructive lines. It is, therefore, the purpose of this work to present the most important sections of this information in a form most useful to designers; briefly, the work will contain information which every designer should know.

To obtain a thorough treatment in a single volume, however, could hardly be expected, so it is proposed to accomplish this in a series of smaller volumes that deal with the most important subjects. Each subject will be covered in a complete and comprehensive manner; including as far as is possible, a description with data on all of the various types of construction; an outline of a proven stress analysis, together with practical examples; as well as an authoritative and detailed discussion on design in all of its phases. By preparing this work in a series of books in this manner, it insures the latest material at the time of publishing either the first or any of the subsequent editions, and it also permits those desiring information on special subjects to procure only the particular volumes in which they are interested.

Although these books are prepared especially for the airplane engine designer, they should also prove invaluable to the designer of all other types of internal combustion engines, as well as to most engineers and students who are interested in these subjects. The greatest care is being exercised in presenting accurate and reliable information, and in every case the analytical methods employed have been tried and proven in practice."

From the Introduction:

"The present volume is the first of the AIRPLANE ENGINE DESIGN SERIES to be presented. This volume will include the major portion of engine design problems requiring mathematics and, naturally, the analytical methods treated in the other volumes in connection with the design of other component parts of the engine must frequently be referred to the dynamics of the engine as herein treated.

An effort has been made to simplify and condense this material into suitable form for the use of the designer, and yet retain its value to the student or those desiring to check certain equations developed. On the whole, the methods employed in the discussion of engine dynamics are quite similar to those in general use, therefore the advantages in the present treatment lie mainly in their simplicity.

The methods for investigating the stresses and bearing loads of crankshafts have probably never been presented before in such a complete form, and as to their value, it is only necessary to state that they have been successfully applied in practice for over a period of six years. It is hoped that these methods will eventually become the standard of all designers in order to insure uniformity of results and facilitate drawing true comparisons between different designs. Another step in the direction of standardization has been undertaken in this volume in the use of a single standard of symbols and abbreviations. The author will feel that this work is justified if it clarifies the designers' problems, or in any way encourages the broader use of analytical investigations.

Acknowledgment is given to Chas. W. Iseler and Harold Caminez, who have so kindly checked the manuscript and offered numerous useful suggestions, and to Lt. S. P. Mills, former Secretary of the Air Service Engineering School, who has carefully read the manuscript with a view of offering criticism as to its value to the student, also to J. B. Johnson, who has reviewed the sections dealing with materials."

Contents include: - Section I: Engine Dynamics - Section II: Crankshaft Design