Scope and Contents Document Type: Book (Technical).Purpose: Authoritative Reference.Authority: Author Expertise.Scope: Technical monograph written for a knowledgable audience by P. V. H. Weems, Lieutenant Commander, United States Navy, Retired. From Preface to Third Edition: ""This edition goes to press under critical war conditions with the purpose of assisting national defense. Material on civil airways and other phases of air navigation, which would have been...