THE VALUE OF ZEPPELINS IN LONG-DISTANCE RECONNOITERING—NAVAL AUXILIARIES

The growing intensity and fierceness of the gigantic struggle between the great nations of the world in the second half of the second year naturally was reflected in the extraordinary activities of the aerial fleets of the combatants. To give in detail the thousands of individual and mass attacks is manifestly impossible in a restricted work of this kind, and we shall have to be satisfied with a description of the more important events in this latest of all warfares.

Undoubtedly the most pronounced feature of aerial combat in 1916 was the complete rehabilitation of the Zeppelin type of rigid airship construction as an invaluable aid to the land and naval forces in the difficult and dangerous task of reconnoitering the enemy forces. There can be no doubt that the frequent raids of the eastern counties of Great Britain were undertaken far more with the idea of gaining as clear an idea as possible of the distribution of British naval units in the North Sea than with the desire of hurling destruction from the sky upon sleeping villages, towns, and, of course, harbors and factories which might be of value to the British military forces. And there also can be no doubt that for this purpose of reconnoitering over immense areas the Zeppelin airship stands to-day unchallenged by any other single means at the disposal of the army leaders.

The German Zeppelin airship carries at present a powerful wireless-sending apparatus, the electric current for which is furnished by one of the motors. These motors, five in number, are of the six-cylinder Mercedes type, furnishing a total of 1,200 horsepower. Four of the motors are usually in service, the fifth being held in reserve, and used in the meantime for furnishing the required electric current. The wireless equipment is stated to have an effective range of about 300 miles, due mainly to the great height of the "sending station." It was this wireless equipment which is now known to have precipitated the great naval battle off the Jutland coast, and to have sent the German fleet to its home base before the full force of the much superior British fleet had a chance to exercise its crushing power.

According to the report of the captain of one of the German battle cruisers, the Zeppelins, of which there were two in the early hours of the battle, sighted a strong British naval force in the North Sea, about two-thirds of the way from the British coast to Helgoland. The information was flashed to Helgoland by the leading Zeppelin, which was hovering more than two miles in the air, commanding an immense area of the North Sea. The approach of the German fleet was unknown to the British, although the Zeppelins could distinguish both fleets from their great height.

As the battle developed and the British battle cruiser squadron became sorely pressed by the superior forces opposed to them, calls for assistance were flashed from them to the main fleet. The Zeppelins, of course, caught the calls and set off at high speed northward with the intention of giving timely warning to the German squadron battling several thousand feet below them against the gradually increasing British force.

The mist which hung over the North Sea made it difficult for the Zeppelin commanders to distinguish objects clearly, but the same mist prevented the British ship crews from sighting the airships in the clouds. When the heavy black smoke from the battleships rushing south at their highest speed was sighted by the northernmost Zeppelin, word of the apparent strength of the reenforcements was flashed to the German commander in chief and the order for retreat was given. While the fleets executed their maneuvers, the British main forces arrived and the greatest battle in naval history took place. Had it not been for the timely warning from the Zeppelins hanging high in the air above the sea, the German fleet might have been overwhelmed by the huge forces rushing south to destroy it. Outnumbered by more than two to one, its only safety lay in retreat—and so heavy had been the fire, that the British commander did not press the pursuit too close. For while the Germans knew to a ship the strength of their adversary, the latter had to reckon with the unknown, hidden possibilities of forces not yet seen. It cannot be denied that the Jutland naval battle was a complete vindication of the use of Zeppelins as naval scouts, a value now recognized by every naval officer in the world.

The second field of action in which the Zeppelin airship has shown a certain measure of success is that of destroying small naval units of the enemy. And not only the German airships have had occasion to show their value, but the French have been especially successful in this work. For several months previous to February, 1916, little had been heard of the activities of the new French dirigibles, which were reported to have been built, although a number of them were continually cruising high in the air above Paris and in the district north of the capital. Occasionally hints were dropped here and there concerning their activity above the Channel and portions of the North Sea, and in the early summer a fairly substantial report reached this country to the effect that the new French lighter-than-air machines were utilized chiefly in "submarine hunting."

In the early stages of the war, when military and naval aviation was trying to adopt peace-time theories to war-time facts, Great Britain attempted to hunt the German submarines with aeroplanes, or hydroaeroplanes; but the method had its serious draw-backs. The aeroplane is of necessity a fast traveling machine; it must make at least forty miles an hour to be able to stay aloft. Whizzing through the air at such speed is not conducive to a careful scrutiny of the surface of the water below, necessary in order to detect the vague, dim outlines of a submerged submarine. At first the pilots of naval aeroplanes had considerable success in locating the submarines, and Germany lost quite a few of them, before the reason was discovered. Some one in Great Britain announced that it was easy to locate a submarine from an aeroplane by the peculiar reflection in the sunlight caused by the fine film of lubricating oil on the surface of the water. As soon as this "tip" was communicated to Germany, submarines discontinued the use of oil for lubrication, employing instead deflocculated graphite. The fuel oil used in the Diesel engines for propulsion on the surface is so thoroughly consumed and the exhaust now is so free of oil that an oil film as an indication of submarine proximity is no longer trustworthy. Besides, the submerged boat might be a friendly one, a fact which was borne upon the British authorities on two separate occasions when scouting aeroplanes reported submarines near, and speedy motor boats rushed to the attack. In one case the British submarine is reported to have been rammed, and in the other—so the story goes—the commander of the submarine liberated a little buoy attached to the outside of the boat, which rose to the surface and informed the watchers above that "a friend is down below—not an enemy!"

The system followed now in the locating and possible destruction of German submarines in the Channel and North Sea by French dirigibles is as follows: The airships, chiefly of the Astra type, travel at a height of not more than 500 feet above the surface of the ocean, while the observers constantly sweep the water within a radius of half a mile with their glasses. Usually the airships are sent ahead at low speed in spirals, or in a series of curves which enable them to cover every square mile of watery area below. As soon as one of these airships sights a submarine traveling submerged, it flashes the news by wireless to destroyers which at the time may be fifty or more miles away, and in the meantime endeavors to remain directly above the submerged boat. Soon the destroyers arrive and, following the direction of the airship, can ram or sink the submarine with almost certain success. The French admiralty claims to have accounted for a number of submarines by this method, but has found that the scheme no longer will work. The German naval department, learning of the airship patrol, has given its submarine commanders orders to travel at great depth during daylight hours in the Channel and the southwestern section of the North Sea, or to go to sleep on the bottom where the sea is too shallow. In the evening the boat makes its escape from the dangerous neighborhood.

The third field of action of airships—devastating hostile countries—is the least valuable, although perhaps the most spectacular of the activities of airships of the Zeppelin type. The damage caused by the numerous Zeppelin raids over England, for instance, is a subject of so much dispute that a true appreciation of their value cannot be formed at present. While the German official bulletins repeatedly declare that great material damage was done by the bombs to military establishments, factories, harbor works, etc., the British statements dwell more upon the number of noncombatants who were killed, and deny the infliction of any material damage.

Information of this kind is considered legitimate secrecy and it is only when files of the British local and trade papers are examined that an inkling of the real damage is obtained. Fires, boiler explosions, railway traffic suspensions, and similar highly suggestive items fill the columns of the papers, after every one of the Zeppelin raids. On only one occasion, February 2, 1916, has the British War Office admitted serious military damage in its official communication. This communication was issued after exaggerated reports of the damage caused had appeared in the German and neutral press, covering the Zeppelin raids of January 30-31, 1916, and February 1, 1916, and admitted officially the following: Bombs dropped totaled 393; buildings destroyed: three railway sheds, three breweries, one tube factory, one lamp factory, one blacksmith shop; damaged by explosions: one munition factory, two iron works, a crane factory, a harness factory, railway grain shed, colliery and a pumping station. "One of the spectacular incidents of this raid was the chase of an express train by the Zeppelin, the train rushing at its utmost speed of seventy miles an hour into a tunnel, disappearing just as the first bombs began to drop. The train remained in the tunnel for more than an hour, waiting for the Zeppelin to fly away!" The official figures of killed and wounded in this raid are given as sixty-seven killed, and 117 injured.

During the month of July, reports of the new German super-Zeppelins began to appear in British reports, and a number of neutral correspondents endeavored to obtain authentic data concerning them. Conflicting descriptions arrived from many sources, and it was not until a Swiss reporter, equipped with extremely powerful glasses, watched the trial flights of two of these super-Zeppelins above Lake Constance, that fairly reliable information could be compiled.

One of these airships leaves Friedrichshafen every week for duty in the North Sea, and the factory on the shore of Lake Constance expects to be able to complete five machines every month after July, 1916. The super-Zeppelin has two armored gondolas, without a visible connection, although it is highly probable that such communication is provided for within the outer envelope. Each gondola carries six machine guns and, in addition, two quick-firing guns, as well as an aerial torpedo-launching device, which was first used in the extensive air raids on England in the last week of July.

The super-Zeppelin contains approximately 1,000,000 cubic feet of gas and has a capacity of ten tons useful load. Of this load, about four tons can be composed of bombs or other munitions, the remainder being needed for fuel, machinery, and the crew, as well as ballast and provisions. The gross weight of a fully equipped and loaded super-Zeppelin is thirty tons, or roughly, 60,000 pounds. The envelope, which heretofore has been painted gray with liquid aluminum paint, now is impregnated thoroughly with finely divided metal, by means of the Schoop metal-coating process, which is heralded as one of the most far-reaching improvements in aerial navigation. By its means the airship envelope is made absolutely impervious to atmospheric influences.

For its protection against antiaircraft fire the new super-Zeppelins carry apparatus in each gondola, producing artificial clouds of such size and intensity as to envelop and shroud completely the entire airship, rendering it absolutely invisible from below. While this cloud expands and gradually grows thinner, the airship rises rapidly in a vertical direction, speeding away while under protection of the self-made clouds.

The motors of the latest Zeppelins weigh only 595 pounds each, although developing 240 horsepower, which means that one horsepower is developed for every three and three-quarter pounds of metal used. They are fitted with twin pumps, double jet carburetors, and are usually operated on mixtures consisting of one part benzol with one part alcohol.[Back to Contents]