CORNELL UNIVERSITY LIBRARY Cornell University Library UG630 .P84 Aerial observation 3 1924 030 744 688 oiin Cornell University Library The original of tliis book is in tlie Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924030744688 AERIAL OBSERVATION AERIAL OBSERVATION The Airplane Observer The "Balloon Observer and the Army Corps Pilot By HAROLD E. PORTER ("Holworthy Hall") Major, Air Service, Officers' Reserve Corps Formerly Captain, Air Service, United States Army Illustrated flARPER y BROTHERS PUBLISHERS NEW YORK AND LONDON AXKUL Obssrvatioh Copyright, 1921, by Harper & Brothers Printed in the United States of America DEDICATION On February ii, igi3, there was held at the Sorbonne, in Paris, under the auspices of L'Association Generale Aeronautique, a public meeting at which the destiny of France was taken out of the lap of the gods, and remolded according to the wishes of the people. It was a meeting which had for its object the adoption of a definite aerial policy as a foster-child of the commonwealth. Without this meeting, and the result of it, there would have been in XQI4 no French Flying Corps, uiell-manned, well-trained, and well-equipped {ac- cording to the highest standards of that time) to guard the pathless- ways above the nation, and to stand as the first, and eventually, after four years of constant and unrivalled achievement, to stand, late in 1917, as the last, bulwark of civilization. The development of aviation in France—which is to say, the de- velopment of modern military aeronautics—is due almost entirely to the little group of statesmen who, without ulterior motive, spoke the truth to France at that public meeting, and thereby nationalized a great ambition. Thenceforward, the French Republic knew— as ours has never known—that great policies, and great visions, are inevitable of success when the impulse springs from the whole citizenry, and not merely from that tiny fragment of it which is called the "government' The impulse of France, a reaction from the logic and eloquence of a few who were trusted and believed, led to public subscriptions and public enthusiasm which in turn led to aeronautical research and experiment, aircraft production, the training of voluntary personnel, and all the manifold preparation which placed the Republic in a condition of readiness when readiness was unexpectedly demanded. Again, this was no trick of politics, nor was it the coup of an Administration; it was a national movement, due to the prophets who foresaw its benefits. There was one man who, regardless of the orders of his physician, rose from a sick-bed, and compelled his will to carry himself to the platform; compelled his voice to preach to his audience the doctrine that the history of France was literally to be written on the clouds. The world has never appreciated this man as a pioneer thinker in aeronautic matters; and perhaps it is because his later grandeur has overshadowed that courageous journey at the end of which there was no glory for him except the consciousness of having risked his health in order that he might loan his genius to his country. To the distinguished sponsor of the early French program, then; to the prophet of a new world; and to the patriot who, thank God, was never a Cassandra to his fellow-people, M. Georges Clemenceau this book is respectfully dedicated. CONTENTS CHAP. y^ PAGE Preface xi I. Introductory i II. The Historical Development of Aerial Obser- vation i6 III. The Training of the Airplane Observer ... 53 IV. Aerial Observation 83 A. General 83 B; Infantry Contact Patrol 86 C. Reconnaissance loi D. Artillery Reglage 133 E. Photography 153 F. Photographic Interpretation 177 G. Ground Camouflage 210 V. The Army Corps Pilot 218 VI. The Balloon Observer 256 A. General 256 B. In the Basket 280 VII. The United States Air Service Before, During, AND After the War 306 VIII. Conclusion 337 ILLUSTRATIONS The Author Frmtiapiect The Observer and His Armament—A. E. F. Pacinop. 58 " Photos Made with Camera Gun 72 " Infantry Contact Patrol 90 " One of Our Own "Archies" in Action ... 100 " Photographic and Visual Reconnaissances . 108 Artillery Firing at a Target Which It Has " Never Seen 134 " A Typical Oblique Photograph 158 " Mosaic Map of the City of Washington, D. C. 160 " Instruction in Mosaics 170 Photograph of the Moulin de Tous Vents " Trenches 180 " Diagram Made FROM the Above Photograph . 180 " Photograph of the St. foiENNE Trenches ... 186 " Diagram Made from the Above Photograph . 186 " Photograph of the Euphrates Trenches ... 208 " Diagram Made from the Above Photograph . 208 " Type "R" Balloon 262 " The Basket of a Caquot 284 " How A Flying Field Looks from the Air . 330 PREFACE BY ELMER HASLETT Major, Air Service, United States Army {Pilot and Observer) . Distinguished Service Cross, Croix de Guerre. Two citations for conspicuous bravery. Oper- ations Officer First Army Corps, Chdteau Thierry, and First Army Observa- tion Wing, St. Mihiel and the Argonne. Author of "Luck on the Wing." War has never been fought successfully by "hunches." Information is the basis of every military action; it has ever been, and it will ever be. Without information, military decisions become a matter of guesswork; and with guesswork the fate of nations is just as safe in the hands of an ignorant plowboy as in the hands of the most highly trained general. War has never been reduced to an exact basis. Every war, every battle, and every phase of every bat- tle is a separate problem. Throughout the ages, mili- tary authorities have been able to do no more than to reduce their experience into a few simple principles which have a fair chance of weathering the revolu- tionary changes in successive wars. Consequently among military critics there has existed always a tendency toward conservatism. On account of this conservatism, I predict that the views of Major Porter (which views I fully share) as to the future of aircraft in national defense will not be received by the high courts of military power without dissenting opinion. But conservatism has now reached the point of detriment, in that it has overshadowed and dimmed the perspective of many of our clearest thinkers. Regardless of the critics, whose views we PREFACE naturally respejct, it seems that no person of responsi- ble intelligence (regardless of military training) can reflect upon the rapid development of aviation with- out realizing that a permanent change has come—not only in the methods of waging war, but also in the bat- tleground in which it must be waged. Within the short space of four years this new arm of the service undertook to dominate, physically, a new element, and did actually dominate it. It provided a battle- ground which completely covered land and sea—the two grounds upon which all former wars were carried out. Moreover, this new ground is one in which only one arm can survive. As rational people, we must base our preparation upon its known advantages. Major Porter presents the thesis that observation is the backbone of aviation. With this thesis I agree, and I submit that it is the main preliminary basis of military action. The tendency of modern warfare is toward mass formations; this principle has already been adopted in regard also to aviation by several first-class nations—upon a few hours' notice the entire air strength of these nations can be moved under one command and possibly in one mass. Deducting down- ward, the nation with a united air force will certainly gain and hold the supremacy of the air. Without air supremacy there is no successful aerial observation. Without successful observation, there is not sufficient military information. Without this, there is no form- ing an intelligent military decision. Without this— we guess. And for my part—and I believe that my opinion is shared by the vast majority of flyers—we want no more guesswork in regard to aviation. We have had enough of it, and of its results. The results were unnecessary casualties. And one must laugh to imagine the air services of our own army, navy, and PREFACE post office, no matter how efficient individually, in an attempt to unravel enough red tape to meet the trained force of any foreign power which understands mass flying and mass action in the air. I firmly believe that a united Air Service, controlled by a separate Department of Air, is the only solution to our aviation problem. Aerial Observation is a subject with many ramifica- tions. No man may specialize in them all. Yet the education of the modem citizen is incomplete unless he has at least a conversational knowledge of the main branches. The ideal method of presenting the whole subject to a layman in order to furnish him with a conversational knowledge of these branches (and of presenting it to a prospective student of observation in order to furnish him with sound general principles) requires certain happy qualifications on the part of the originator of the method. First, the book should be written by a man with perspective. Secondly, in addition to intensive study, the author should have made many flights, and actu- ally practiced his theories in the air. He should have been a true observer—not merely an officer with the military rating of Observer—but one who, in addition to seeing, realizes what he has seen. Major Porter fills the requirements better than any one I know, or know of. We have got the right man, and therefore we have got the right book.