AUTHOR'S PREFACE 



THE science of Aeroplane Performance Calculations has become 

 extremely important with the rapid advance of Aeronautics and 

 has been developed to a very high degree. The Author has 

 experienced considerable difficulty, however, in finding any 

 detailed literature on the subject, and it is for this reason that 

 he has written this book in the hope that Aeronautical Engi- 

 neers and Designers will find it useful in supplying their special 

 need for a practical and up-to-date handbook. As Designers 

 will be aware, the restricted information published up to the 

 present time has scarcely touched the fringe of the subject, and 

 it is hoped that the readers of this book will find it to be a 

 comprehensive and efficient instrument for saving time, since 

 Aeroplane Performance Calculations can be very laborious if a 

 clear and systematic method is not used. 



The Author has given a considerable amount of thought and 

 attention to the arrangement of the subject matter, and has 

 divided it into three parts, namely : 



Part I. Descriptive and Theoretical. 

 Part II. Practical Procedure. 

 Part III. Illustrative Examples. 



The Aeronautical Engineer, using the volume as a handbook 

 in his office, will find Part II. of greatest service to him, and for 

 this reason all the formulae, data, and curves required are col- 

 lected in this part, which, being in the middle, is easier to keep 

 lying open on the desk whilst in use than the end sections 

 would be. This centre part also contains directions for use of 

 formulae, and forms of tables for use in calculating a feature 

 which will be found a great time-saver. 



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