AIRSHIP MANUAL D'ORCY'S AIRSHIP MANUAL D'ORCY'S AIRSHIP MANUAL AN INTERNATIONAL REGISTER OF AIRSHIPS WITH A COMPENDIUM OF THE AIRSHIP'S ELEMENTARY MECHANICS COMPILED AND EDITED BY LADISLAS D'ORCY, M.S.A.E. PUBLISHED BY THE CENTURY CO. NEW YORK : MCMXVII COPYRIGHT, 1917, BY THE CENTURY Co. Published October, 1917 THE ILLUSTRATIONS ARE FROM SPECIAL DRAWINGS BY GEO. F. MCLAUGHLIN. THE PHOTOGRAPHS ARE KINDLY LENT BY MR. HENRY WOODHOUSE FROM HIS PRIVATE COLLECTION. 7 A la Me'moire des Ae'rostiers de la Republique et de ses Allies marts pour la Liberte des Peuples. To the Memory of the Aeronauts of the French Republic and of her Allies who died for the Freedom of the Peoples. 369966 CONTENTS PAGE PAGE ALLIES INTRODUCTION I V AIRSHIP LOSSES OF THE 199 ELEMENTARY MECHANICS OF THE AIRSHIP 2 VI GERMANY'S AIRSHIP LOSSES 2OI THE AIRSHIP IN THE GREAT WAR 39 VII THE GERMAN AIRSHIP RAIDS ON GREAT 1 I THE WORLD AIRSHIP BUILDERS . 5 BRITAIN 205 II THE WORLD'S AIRSHIP PRODUCTION . l8 S VIII THE COMMERCIAL AIRSHIP FLEETS OF 1914 209 MILITARY AIRSHIP FLEETS . III THE IX THE WORLD'S AIRSHIP SHEDS .... 313 IV COMPARATIVE STRENGTH OF THE MILITARY AIRSHIP FLEETS 197 INDEX 229 NOTICE In compliance with the recommendations of the National Advisory Committee for Aeronautics, all data in D'Orcy's Airship Manual are expressed in the metric system. For the convenience of readers unfamiliar with the metric system the approximate equivalents of the metric units employed are herewith given in English units: I meter (m.) = 3% feet. = i kilometer (km.) f statute mile. = I cubic meter (cbm. or me.) 353- cubic feet. ' = I kilogram (kg.) 2^ pounds. I metric ton = 2,200 pounds. INTRODUCTION The present volume is the result of a methodical available, complete data for every airship of 500 investigation extending over a period of four years cubic meters and over, that has been laid down in the course of which many hundreds of English, since 1834. Smaller airships are listed only if they French, Italian, German and Spanish publications embody unusual features. and periodicals dealing with the present status as It has been attempted to furnish here the most well as with the early history of airships have care- up-to-date information regarding the gigantic fleet fully been consulted and digested. It has thus of airships built by Germany since the beginning become possible to gather under the cover of a of the Great War, a feature which may, in a certain handy reference-book a large amount of hitherto measure, repay the reader for the utter lack of data widely scattered information which, having mostly on the Allies' recent airship constructions, which been published in, foreign languages, was not im- had to be withheld for military reasons. A revised mediately available to the English speaking public. and enlarged edition of D'Orcy's Airship Manual, The information thus gathered is herewith pre- in which all the airships built during the Great sented in two parts; one being a compendium of War will be listed and their features duly discussed, the elementary principles underlying the construc- will be issued upon the termination of the war. tion and operation of airships, the other constitut- Ladislas ing an exhaustive, but tersely worded register of d'Orcy, the world's airshipping which furnishes, whenever New York City (U. S. A.) ELEMENTARY MECHANICS OF THE AIRSHIP Definition and Classification. The airship be- The very nature of the airship's sustentation, longs, with its immediate forerunner, the free bal- which permits to assimilate the airship to the loon, to the family of static aircraft. ship of the sea, sufficiently justifies the retention Static aircraft derive their sustentation from a of the term "airship" and the condemnation of is than air free the hull which filled with a gas lighter ; term "dirigible," the customary abbreviation balloons and airships consequently float in the of "dirigible balloon," which may reasonably be atmosphere, like ships float on the sea, by virtue applied to the aeroplane too, since it fails to specify of buoyancy. the type of aircraft it is supposed to describe. The airship's sustentation is, unlike that of the The hitherto customary division of airships into aeroplane, independent of forward motion, in other the rigid, semi-rigid, and non-rigid types, which words, the airship can stay aloft without expending was based on primitive and now obsolescent con- engine power, in which case it drifts with the pre- ceptions, has been found totally inadequate to ex- vailing wind like a free balloon. press the features of novel sub-types which have The airship is the outcome of a century-long more recently been produced; it has therefore been endeavor to endow the free balloon with inde- deemed advisable to adopt a new nomenclature, pendent velocity whereby it would be able to based on the constructional features of the hull navigate the atmosphere regardless of winds in which alone permit fundamental differentiation. any direction desired; hence the now little used Whereas every airship hull presents to the rela- terms of "navigable" and "dirigible balloon" tive wind an essentially rigid body, it follows that " " under which the airship first became known. the term rigid cannot logically be applied to one particular airship type, the same argument* the hub of which a steel hawser runs from stem to " " " "barring also the terms semi-rigid and non- stern. Both the hawser and the radial truss wires rigid." Consequently all airships in which the are fitted with turnbuckles whereby the whole frame- shape of the hull is rendered permanent by means work may be tightened up when required. The of a rigid structure, the hull frame, are here termed radial, or tie, trusses form the compartments in structure airships, whereas all those in which the which from 1 8 to 24 individual gas-cells are housed; shape of the hull is maintained through internal the cells are drum-shaped and are fitted with an pressure are here listed as pressure airships. inflation appendix and a relief-valve. Owing to Structure Airships. The fundamental principles the constancy of displacement realized by the hull of the structure airship were first laid down in a. frame, no deformation will occur through a con- patent taken out in 1873 DY the Alsatian engineer traction of the hydrogen, whereas an expansion Joseph Spiess. Twenty years later David Schwarz of the gas will be promptly relieved by the auto- of Zagreb (Croatia) built at Petrograd a structure matic and manually operated valves; but as the airship which was the earliest representative of latter process may create an explosive mixture its kind, but it was a failure. Shortly afterwards between the gas-cells and the outer cover, it is Count Ferdinand von Zeppelin, a German cavalry necessary to keep this space constantly ventilated general, emulated Schwarz, whose patents he had by forced draught, the escaping hydrogen being purchased, and eventually succeeded in developing expelled through shafts leading to the roof. These by gradual improvement of design the highly effi- shafts are fitted with automatic valves which can cient modern structure airship. Structure airships also be manually controlled. are characterized by a rigid hull frame generally As a further measure of precaution recent Zeppe- built up of longitudinal girders which are connected lin airships have the lower half of the outer skin at intervals by polygonal ties; the resulting frame- treated with a gas-proof varnish to prevent its pene- work is covered with a waterproof, but non-gas- tration by the heavy and impure gas collecting in tight, fabric skin. On Zeppelin airships every sec- the bottom of the gas-cells, which on coming in ond tie is braced athwartships by a radial wire truss contact with the engine exhaust might set the resembling the spokes of a bicycle wheel, through vessel on fire. The portions of the hull which are in the immedi- wood girders are employed. The wooden girders ate neighborhood of the propellers are protected of the Spiess airship were of tubular form, built against possible injury from this source by a plating in halves and glued together. of veneer. The longitudinals and polygonals of Zeppelin air- It has been reported that on the latest Zeppelin ships are built up of punch-pressed corner-rails and airships the gas-cells are connected with a storage X-pieces; they are riveted together so as to form tank whither the expanding hydrogen escapes triangular girders. The only authoritative state- under rising pressure through automatic valves ment regarding the strength and weight of these and whence it can be pumped back into the gas- girders is one by Count Zeppelin to the effect " cells when the hydrogen contracts. Whatever that on his first airship the aluminum which truth there be in this so far unverified statement, served as the material of construction had a specific it is obvious that such a storage tank would greatly weight of 2.7 kg. and a tensile strength of 33 kg. obviate the structure airships' great drawback of per square meter of surface. The frames proper losing gas and consequently lift in the process of (longitudinals) were built of angle and T-bars and regulating variations of gas-pressure. A similar the bracing girders (polygonals) of angle bars. The arrangement incidentally existed on the first weight of these frames, as applied to the construc- Schutte-Lanz airship, where the excess of gas gen- tion, was '0.9 and 1.8 kg. per meter length, this erated by rising pressure was forced by means of a being equivalent to 0.516 kg.